Coyote Blog

Up until now, the retreat of Arctic ice to 30 year lows has been credited, without proof, to global warming.  This never made a lot of sense to me, since at the same time Antarctic sea ice was hitting an all-time high.  Over at Climate Skeptic, I discuss a new NASA study that proposes that Arctic sea ice melting over the last decade has been due mainly to shifting wind patterns that basically push the ice into warmer waters where it melts faster.

I am sure everyone has heard that Arctic sea ice is, as the National Geographic described it, at an "all-time low."  Of course those would expect the words "all-time" to mean just that will be disappointed to learn that they really mean "since 1979 when we started measuring it by satellite."

At Climate Skeptic, I write that it has come to my attention that the earth has two poles, and it's odd no one talks about the other one.  Maybe they forgot?  Well it turns out that Antarctic sea ice is at an all time high (using the term in the same way that National Geographic does). 

As an end note, I also discuss Glacier Bay, Alaska.  It turns out the glaciers there are retreating, but about 99% of the retreat occurred between 1793 and 1907. 

I had a call today from a reporter at the Christian Science Monitor who wanted to discuss climate skepticism.  What a disaster of an interview I am!  He would ask an open-ended question, and off I would go into feedback theory and then to acoustics and then into helicopter dynamics and back to the ice age and then to temperature measurement in Tucson.  I try to follow 6 trains of thought simultaneously and the result is a mess. 

The poor reporter was quite friendly and ended with "I am not sure where we are going with this story" which is the universal reporter speak for "your interview was such a mess I am not sure how we would ever use it."  LOL.  Only by writing, with the implicit governor applied by the keyboard, am I able to organize my thoughts well.  Which is why I have never invested in a computer dictation product - I shudder to think what I would find on the page after a session.  Which reminds me of the early Doonesbury cartoons with Duke when he was a reporter at the Rolling Stone, when he would come into the his editor's office and claim to have dictated some really powerful stuff, only to find a garbled drug-induced mess, which was obviously a reference to Hunter S. Thompson, who... oh crap, I'm doing it again.

Best thing I have read in a long time:

Imagine an egalitarian world in which all food is organic and local,
the air is free of industrial pollution, and vigorous physical exertion
is guaranteed. Sound idyllic?

But hold on"¦ Life expectancy is 30 at most; many children die at or
soon after birth; life is constantly lived on the edge of starvation;
there are no doctors or dentists or modern toilets. If it is
egalitarian it is because everyone is dirt poor, and there is no
industrial pollution because there are no factories. Food is organic
because there are no pesticides or high technology farming methods. As
a result, producing food means long hours of back-breaking physical
work which may end up yielding little.

There is "“ or at least was "“ such a
place. It is called the past. And few of us, it seems, recognise the
enormous benefits to humanity of escaping from it. On the contrary,
there is a pervasive culture of complaint about the perils of affluence
and a common tendency to romanticise the simple life.

Via Hit and Run.  I made a fairly similar point here when I compared California "robber baron" Mark Hopkins mid-19th century house to one a friend of mine used to own in Seattle:

One house has hot and cold running water, central air conditioning,
electricity and flush toilets.  The other does not.  One owner has a a
computer, a high speed connection to the Internet, a DVD player with a
movie collection, and several television sets.  The other has none of
these things.  One owner has a refrigerator, a vacuum cleaner, a
toaster oven, an iPod, an alarm clock that plays music in the morning,
a coffee maker, and a decent car.  The other has none of these.  One
owner has ice cubes for his lemonade, while the other has to drink his
warm in the summer time.  One owner can pick up the telephone and do
business with anyone in the world, while the other had to travel by
train and ship for days (or weeks) to conduct business in real time.

Best thing I have read in a long time:

Imagine an egalitarian world in which all food is organic and local,
the air is free of industrial pollution, and vigorous physical exertion
is guaranteed. Sound idyllic?

But hold on"¦ Life expectancy is 30 at most; many children die at or
soon after birth; life is constantly lived on the edge of starvation;
there are no doctors or dentists or modern toilets. If it is
egalitarian it is because everyone is dirt poor, and there is no
industrial pollution because there are no factories. Food is organic
because there are no pesticides or high technology farming methods. As
a result, producing food means long hours of back-breaking physical
work which may end up yielding little.

There is "“ or at least was "“ such a
place. It is called the past. And few of us, it seems, recognise the
enormous benefits to humanity of escaping from it. On the contrary,
there is a pervasive culture of complaint about the perils of affluence
and a common tendency to romanticise the simple life.

Via Hit and Run.  I made a fairly similar point here when I compared California "robber baron" Mark Hopkins mid-19th century house to one a friend of mine used to own in Seattle:

One house has hot and cold running water, central air conditioning,
electricity and flush toilets.  The other does not.  One owner has a a
computer, a high speed connection to the Internet, a DVD player with a
movie collection, and several television sets.  The other has none of
these things.  One owner has a refrigerator, a vacuum cleaner, a
toaster oven, an iPod, an alarm clock that plays music in the morning,
a coffee maker, and a decent car.  The other has none of these.  One
owner has ice cubes for his lemonade, while the other has to drink his
warm in the summer time.  One owner can pick up the telephone and do
business with anyone in the world, while the other had to travel by
train and ship for days (or weeks) to conduct business in real time.

I was trying to think about what I wanted to do for my last post in my recent orgy of global warming writing.  My original attempt to outline the state of the climate skeptic's case ballooned into 80+ pages, so there may be many people who rationally just have no desire to tackle that much material.  So I decided for this last post to try to select the one argument I would use if I had only 60 seconds to make the climate skeptic's case. But how do you boil down 80 pages to a few simple statements?

I'm not that interested in the Sun or cosmic rays -- they are interesting topics, but its dumb to try to argue we overestimate our understanding of man's impact on climate only to counter with topics we understand even less.  One of the reasons I wrote the paper in the first place was because I thought recent skeptical documentaries spent too much time on this subject.  And I would not get into tree rings or ice cores or other historic proxy data, though there is a lot happening in these areas.  I wouldn't even delve into the hysterical treatment of skeptics by man-made climate advocates  -- these are ad hominem issues that are useful to understand in a more comprehensive view but don't make for strong stand-alone arguments.

Anyway, here goes, in a logic chain of 8 steps.

1. CO2 does indeed absorb reflected sunlight returning to space from earth, having a warming effect.  However, this effect is a diminishing return -- each successive increment of CO2 concentrations will have a much smaller effect on temperatures than the previous increment.  Eventually, CO2 becomes nearly saturated in its ability to absorb radiation.  The effect is much like painting a red room with white paint.  The first coat covers a lot of red but some still shows through.  Each additional coat will make the room progressively whiter, but each successive coat will have a less noticeable effects than the previous coat, until the room is just white and can't get any whiter.
2. In the 20th century, the UN IPCC claims Earth's surface temperatures have increased by about a 0.6 degree Celsius (though there are some good reasons to think that biases in the installation of temperature instruments have exaggerated this apparent increase).  To be simple (and generous), let's assume all this 0.6C increase is due to man-made greenhouse gasses.  Some may in fact have been due to natural effects, but some may also have been masked by man-made sulfate aerosols, so lets just call man-made warming to be 0.6C. 
3. Since the beginning of the industrial revolution, it is thought that man has increased atmospheric CO2 concentrations from 0.028% of the atmosphere to 0.038% of the atmosphere.  Since scientists often talk about the effect of a doubling of CO2, this historic rise in CO2 is 36% of a doubling.
4. Using simple math, we see that if temperatures have risen 0.6C due to 36% of a doubling, we might expect them to rise by 1.67C for a full doubling to 0.056% of the atmosphere.  But this assumes that the rise is linear -- and we already said (and no one denies) that it is in fact a diminishing return relationship.  Using a truer form of the curve, a 0.6C historic rise for 36% of a doubling implies a full doubling would raise temperatures by about 1.2C, or about 0.6C more than we have seen to date (see chart below).   This means that the magnitude of global warming in the next century might be about what we have seen (and apparently survived) since 1900.



5. Obviously, there is some kind of disconnect here.  The IPCC predicts temperature increases in the next century of 4-8 degrees C.  Big difference.  In fact, the IPCC predicts we will get a 0.5C rise in just 20 years, not 70-100.  Whereas we derived a climate sensitivity of 1.2 from empirical data, they arrive at numbers between 3 and 4 or even higher for sensitivity.  The chart below shows that to believe sensitivity is 3, we would have to have seen temperature rises due to man historically of 1.5C, which nobody believes. 

   

   So how do they get accelerating temperatures from what they admit to be a diminishing return relation between CO2 concentration and temperature? And for which there is no empirical evidence?  Answer:  Positive feedback.

6. Almost every process you can think of in nature operates by negative
   feedback.  Roll a ball, and eventually friction and wind resistance bring
   it to a stop.  Negative feedback is a ball in the bottom of a bowl; positive feedback is a ball perched precariously at the time of a mountain. Positive feedback
   breeds instability, and processes that operate by positive feedback are
   dangerous, and usually end up in extreme states -- these processes tend to
   "run away" like the ball rolling down the hill.  Nuclear fission, for example, is a positive feedback process.  We should be happy there are not more positive feedback
   processes on our planet.  Current man-made global warming theory, however, asserts that our climate is dominated by positive feedback.  The IPCC posits that a small increase in temperature from CO2 is multiplied 2,3,4 times or more by positive feedbacks like humidity and ice albedo.
7. There are three problems with these assumptions about positive feedback.  One, there is no empirical evidence at all that positive feedbacks in climate dominate negative feedbacks.   The 20th century temperature numbers we discussed above show no evidence of these feedbacks.  Two, the long-term temperature record demonstrates that positive feedbacks can't dominate, because past increases in temperature and CO2 have not run away.  And three, characterizations of stable natural processes as being dominated by positive feedback should offend the intuition and common sense of any scientist.
8. An expected 21st century increase of 0.5 or even 1 degree C does not justify the massive imposed government interventions that will be costly both in dollars and lost freedoms.  In particular, the developing world will be far better off hotter by a degree and richer than it would be cooler and poorer.  This is particularly true since sources like an Inconvenient Truth wildly exaggerate the negative effects of global warming.  There is no evidence tornadoes or hurricanes or disease or extinction are increasing as the world warms, and man-made warming advocates generally ignore any potential positive effects of warming.  As to rising sea levels, the IPCC predicts only a foot and a half of sea level rise even with 4 or more degrees of warming.  Sea level rise from a half to one degree of warming would be measured at most in inches.

OK, so that was more than 60 seconds.  But it is a lot less than 80 pages.  There is a lot of complexity behind every one of these statements.  If you are intrigued, or at least before you accuse me of missing something critical, see my longer paper on global warming skepticism first, where all these issues and much more (yes, including tree rings and cosmic rays) are discussed in more depth.

The table of contents for the rest of this paper, . 4A Layman's Guide to Anthropogenic Global Warming (AGW) is here.  Free pdf of this Climate Skepticism paper is here and print version is sold at cost here

There is no area in global warming discussions where AGW
advocates have done more to shoot down their own credibility than in the
absolutely egregious science and absurd claims that have been made about the
potential negative effects of global warming.  If AGW advocates are frustrated
that skeptics question their science and their credibility, they need to look
no further than their own claims on global warming effects, which are so easy
to prove wrong that it causes people like me to question everything else they
say.

Why only bad stuff?

Whenever global warming is discussed in the press, the
consequences are all universally bad.  Floods, famine, drought,
pestilence, disease "“ they are all commonly predicted results of global
warming.  But it is worth noting that in the 1970's, when climate
scientists and the press were in a panic over global cooling, the predicted
results were"¦ floods, famine, drought, pestilence, disease.  The
implication is that we currently happen to be balanced on the knife edge of
exactly the optimum world temperature for mankind.  Any change warmer or
cooler results in net negative consequences.

This, of course, seems an odd coincidence.  Since man
evolved into homo sapiens, he has experienced a wide range of cooler and
warmer temperatures than we experience today.  It seems frankly amazing
that in the mid 20^th century we happened to be sitting at the
absolute ideal temperature for modern technological society and
agriculture.  Now, I guess you can argue that our society has made
enormous investments based on the locations of the best crop lands, the height
of the oceans, the typical paths of storms, etc., and that shifts in any of
these would force an expensive restructuring of these investments.
However, it is also worth noting that from the bottom of the Little Ice Age to
say 1980, the world warmed at least a degree, and no one really
noticed!  Everyone was still talking about cooling!

So I think that any honest analysis of the effects of global
warming would have to acknowledge that there are likely both positive and
negative effects.  While some areas may experience heat-induced droughts,
other will be wetter as more moisture from the oceans is evaporated.
While some crops will struggle, others, particularly in northern latitudes, will
thrive due to longer growing seasons.  For each crop of vegetables that
wilt in a heat wave there will be a crop of citrus that didn't freeze.
While more may die from the heat, fewer will die from the cold.  These may
still net to a negative sum, but that net sum will be substantially less
negative than a one-sided look at only the downsides of warming would arrive
at.

One reason that warming impact analysis is hard is because while we may talk
about the world warming a degree or two, the world does not warm evenly.
Most climate models show the most warming on dry winter nights  (Siberian
winters, for example, get a disproportionate share of the warming).  An
extra summer degree in Arizona would suck; an extra winter degree in Siberia
would probably be welcomed, and would likely extend growing seasons.

In the rest of this chapter, I will spend some time with a number of the
most common "scary results" from global warming.

Ice melting / ocean rising 

In An Inconvenient Truth, Al Gore claims that oceans will
rise twenty feet due to global warming.  Helpfully, a number of websites
have been created to show what parts of the world (including much of Florida)
would sink beneath the oceans like Atlantis with a 20-foot rise in sea level.

Fortunately, even most AGW supporters believe that Gore is
wildly exaggerating, at least for any time period less than a couple of
centuries.  The Fourth IPCC report (see chart below) predicts sea level
rise by the year 2100 of "¦ 12-15 inches.  And remember that this is based
on forecasts of both CO2 production and climate sensitivity to CO2 that are
arguably high by a factor of two or more.  From the fourth IPCC report
(different columns are for different starting CO2 forecasts):

By the way, to give a sense of scale, the IPCC estimates
that the oceans have already risen about 0.2 meters in the last 130 years or
so:

One other interesting thing you can see from the sea level
forecast chart is that even the IPCC considers ice melting virtually
irrelevant.  That is because most of the surface level increase is from
thermal expansion of the water as the oceans warm.  In the A1B case, for
example, net worldwide ice melt raises oceans by about 4 inches in the next
hundred years. 

This last conclusion may seem crazy to anyone who has
watched the media of late or seen Mr. Gore's movie.  Images of ice
crashing into the ocean and sea ice retreating are common fodder for global
warming visuals.  But the fact is that ice, like everything else in
climate, is complicated.

• North Pole:  Arctic sea ice melting is totally
       irrelevant to ocean surface levels.  Since the ice floats, even a
       100% melting of the Arctic ice will not change sea level one bit, just as
       ice melting in your glass of water does not cause your glass to
       overflow. 

But some may argue that this ducks the
question.  Does current, well-documented retreat of artic ice sheets
provide independent confirmation of the magnitude of AGW?  In fact, though
ice sheets are retreating, this seems to be part of a two hundred year trend
that began long before man was burning fossil fuels in any quantity:

• Alpine Glaciers:  We know that many Alpine
       glaciers around the world are retreating.  Some of this is surely
       from global warming, but some is also from fluctuations in
       precipitation.  In many cases, we have documented evidence that these
       glaciers have been retreating since the 19^th century, and that
       they have been less extensive in the past.

Reid A. Bryson is Emeritus Professor and founding
chairman of the University of Wisconsin Department of Meteorology"”now the
Department of Oceanic and Atmospheric Sciences and a member of the United
Nations Global 500 Roll of Honor.  When asked about
the retreat of Alpine glaciers, he says, "What do they find when the ice
sheets retreat, in the Alps?  A silver mine! The guys had stacked up their
tools because they were going to be back the next spring to mine more silver,
only the snow never went," he says. "There used to be less ice than now. It's
just getting back to normal."

Alaska Geographic published a chart of the retreat
of the glaciers at Glacier Bay, Alaska, showing most of the retreat occurred before
the 2^nd half of the 20^th century:

One special note should be made of the glaciers on
Kilimanjaro, because their retreat over the last 125 years has been
well-documented and played a starring role in An Inconvenient Truth.  Analysis
has shown that most the glacial retreat at Kilimanjaro occurred before 1953
(and therefore before most recent warming) and that the retreat has
more to do with moisture in the air than with global warming.  One
wonders why the movie, with glacial retreats around the world that are provably
due to warming, would focus on one that is probably not due to warming.

· Greenland: 
Greenland has a lot of ice, and there is not much doubt that if it all melted,
the oceans would rise a lot.  However, we know that in the middle ages,
Greenland was much warmer and had less extensive ice coverage (thus the name
Greenland and the successful attempt to farm it for over a century)

While there is a lot of discussion about whether
the Medieval Warm Period extended worldwide, most accept that it did cover the
North Atlantic, including Greenland.  Boreholes, such as the Dahl-Jensen
below, seem to prove out our historical information, showing a temperature peak
around the year 1000.

· Antarctica:
Something like 80-85% of the world's ice is in Antarctica.  And no one
really thinks it is melting or going to melt.  In fact, if you look at the
marks on the IPCC chart above for the contribution of Antarctic ice to ocean
levels, it has a net negative impact, which means the IPCC actually expects the
Antarctic ice sheet to grow, not melt.

Whoa, that can't be right!  Mr. Gore showed those videos of ice retreating
in Antarctica.  Well, yes, sort of.  Scientists expect that global
warming will make the sea currents that circle Antarctica a bit warmer, leading
to more precipitation and more snowfall on the continent.  Besides,
Antarctica is so damn cold that raising temperatures a few degrees is not going
to melt anything. 

The one exception is the Antarctic Peninsula, which
sticks out into the warmer oceans.  This land area, representing about 2%
of the Antarctic land mass and even less of its total ice sheet, is expected to
warm and lose ice while the other 98% gains ice.

Guess what?  Mr. Gore chose that little 2% to
illustrate his movie.  Was he ignorant of the choice he was making, or did
he know exactly what he was doing, telling the literal truth (that the
peninsula is melting) but leading viewers to the wrong conclusion overall about
Antarctic ice?

By the way, one last interesting
fact that frankly, scientists don't fully understand is the fact that the South
Pole is really not experiencing any warming.  While the warming at the
north pole exceeds the global average, the south pole shows little or no
anomaly.

Hurricanes & Tornados

Alter Hurricane Katrina, the media storyline focused
strongly on the role global warming may have played in increasing hurricane
power and activity.  Lost in the rush to blame global warming was the fact
that Katrina, when it made landfall, was not even a category 5 hurricane, and
its devastation was due more to  a city sited below sea-level that did a
poor job of managing its storm protection.

In fact, many hurricane experts do not agree with the argument
that warming oceans can lead to more and stronger hurricanes.  In fact,
hurricane activity is more related to the difference in temperatures between
the cold and warmer waters, a difference AGW theory says should decrease rather
than increase.  So is there reason to believe hurricanes are on the rise
as global temperatures warm?  The answer, as shown below, seems to be no:

But what about storm damage?  It certainly seems like
recent hurricanes have resulted in far more economic damage.  And they
have, but for the simple reason that over the last several decades, Americans
have put billions of dollars of expensive homes and other facilities in
vulnerable Gulf and Atlantic coast locations.   Several years ago, Dr. RA Pielke and CW Landsea
(that can't really be the name of a scientist studying coastal strikes by
hurricanes) attempted to correct hurricane damage numbers for the density and
value of coastal real estate:

By this reckoning, it is hard to see any trend.

Another claim Mr. Gore makes in An Inconvenient Truth
is that 2004 was the most active year for tornadoes ever in the United States,
and that there has been a steady trend in increasing tornados as the globe has
warmed.

And certainly if you look at the raw numbers, you might be
worried:

But there is a little something Mr. Gore fails to
mention.  During this time period, from 1950 to 2000, the technology and
network for detecting tornados has improved vastly.  From the NOAA

With increased national doppler
radar coverage, increasing population, and greater attention to tornado
reporting, there has been an increase in the number of tornado reports over the
past several decades. This can create a misleading appearance of an increasing
trend in tornado frequency. To better understand the true variability and trend
in tornado frequency in the US, the total number of strong to violent tornadoes
(F3 to F5 category on the Fujita scale) can be analyzed. These are the
tornadoes that would have likely been reported even during the decades before
Dopplar radar use became widespread and practices resulted in increasing
tornado reports. The bar chart below indicates there has been little trend in
the strongest tornadoes over the past 55 years.

Oops!  In fact, tornado frequency seems to be falling
as temperatures warm.  Do you think this was another honest mistake, like
with Antarctica, or did Mr. Gore purposefully obfuscate the real story?

Temperature Extremes

Another argument is that global warming will lead to more temperature
extremes, particularly record sweltering highs.  That seems logical
enough, but Bruce Hall actually
compiled the data and found something interesting.  He created a data base
for each state which shows in what year that state's monthly temperature
records were set.   So for each state, he has the years when the
twelve monthly high temperature records were set (e.g. year of highest Arizona
Jan temp, year of highest Arizona Feb temp, etc.) and the years when the twelve
monthly low temperature records were set.  Here, for example, is his data
for Arizona:

So, for example, the record for the highest July temperature was set in 1905
at Parker, Arizona with a scorching 127 degrees.  The entry in his
database would then be Arizona-July:  1905.  He notes that there is a
bias in the data toward more recent years, since if the record was set in 1905
and tied in 1983, only the newer 1983 date will show in the data.  I would
also observe that this data is uncorrected for urban heat island effects (as
cities urbanize they get hotter, and effect that is different than CO2-cause global
warming and is usually corrected for in global warming studies).  There is
also a bias towards the present in having more measurement points today than
100 years ago:  More measurement points means that, over a state, one is
more likely to pick up the true high (or low).

Though I have
other problems with the anthropogenic global warming hypothesis, I have
never really doubted that the world has warmed up over the last century.
So even I, a skeptic, would expect a disproportionate number of the all-time
high temperatures to be in the last decade, particularly without UHI correction
and with the bias discussed above.  The global warming folks would argue
that the effect should be doubly pronounced, since they claim that we are
seeing not just a general heating, but an increase in volatility (ie more
extreme variation around the mean).

But Hall doesn't find this when he graphs the data.
Take the 600 state monthly high temperature records that exist on the books
today (50 states times 12 months) and graph the distribution of years in which
these records were set:

Assuming about 120 years of data, you should expect to see a high
temperature record on average in a database of 600 records at 5 per year, which
is precisely where we have been of late and well below the record years in the
thirties (remember the dust bowl?) and the fifties. It seems to actually show a
reduction in temperatures or volatility or both.

This may seem impossible "“ how can the mean increase without causing a lot
more new highs?  But remember what we discussed earlier "“ global warming
is expected to be seen disproportionately in nighttime and winter
temperatures.  This means that the mean can increase even as daytime
summer highs don't increase much.  In a sense, is the lows, not the highs,
that are getting higher.

Vincent et al in 2005 did a study of temperature trends in South America
from 1960-2000.  What they observed is exactly what we discussed
here:  The number of warm days and cold days did not really change.
The warming trend showed up as a decrease in cold nights and an increase in
warm nights, meaning effectively that the diurnal (across 24 hours) temperature
variation is narrowed. 

It's a little hard to be scared by this.

Extinction and Disease

Biologist Josef Reichholf was
interviewed recently in der
Spiegel.  He is a strong conservationist, and certainly has his axe to
grind with industrial society.  In fact he blames industrial agriculture
and modern development for problems that species face. 

Many species are certainly
threatened, but not by climate change"¦.Many species have already fled from the
countryside to the cities, which have been transformed into havens of
biodiversity. We are also seeing another interesting phenomenon: Major cities,
like Hamburg, Berlin and Munich, have formed heat islands where the climate has
been two or three degrees warmer than in the surrounding countryside for
decades. If higher temperatures are truly so bad, why do more and more animals
and plants feel so comfortable in our cities?

On the contrary, there is much to
be said for the argument that warming temperatures promote biodiversity. There
is a clear relationship between biodiversity and temperature. The number of
species increases exponentially from the regions near the poles across the
moderate latitudes and to the equator. To put it succinctly, the warmer a
region is, the more diverse are its species.

OK, but what about those polar bears?  We have all seen
the media pictures of bears stranded on blocks of ice, as if all the arctic has
melted out from under them.  Well, it turns out that polar bears have
survived much warmer conditions.  We know polar bears existed as a
separate species at least 125,000 years ago, and in the intervening years,
there have been periods where Arctic sea ice melted completely during the
summer months.  And yet polar bears still exist today.  Polar bears
may be threatened by man's hunting and encroachment on its hunting grounds, but
not likely by our fossil fuel combustion.

AGW fear-mongering also extends to breathless predictions of
increases in "tropical" diseases.  Reichholf also takes on this canard:

Many people truly believe that
malaria will spread as temperatures rise. But malaria isn't even a true
tropical disease. In the 19th century, thousands of people in Europe, including
Germany, the Netherlands and even Scandinavia, died of malaria, even though
they had never gone abroad. That's because this disease was still prevalent in
northern and central Europe in previous centuries. We only managed to eliminate
malaria in Europe by quarantining the sick, improving hygiene and draining
swamps. That's why I consider it virtually impossible that malaria would return
to us purely because of climate change. If it does appear, it'll be because it
has been brought in somewhere.

Most of the world's leading tropical disease experts tend to
agree with Reichholf.  In fact, I would argue that diseases like Malaria
are not diseases of the tropics but diseases of poverty and
under-development.  Malaria is prevalent in Africa not because Africa is
hot but because Africa is poor.  Asian tropical countries that have developed
substantially over the last several decades have also greatly reduced
malaria.  In fact, as I will discuss in later sections, by reducing world
economic growth and slowing development in the third world in the name of CO2
reduction, we will actually increase rather than reduce these diseases.

Collapse of the Gulf Stream and Freezing of Europe

One of the recent hysteria's has been that global warming
will cause the Gulf Stream to collapse as Atlantic circulation patterns are
radically altered, thus leading to the freezing of Europe.  More sober
scientists have since essentially said "nevermind."  The Gulf Stream and
Atlantic circulation patterns are far more robust than this theory assumed,
and, even if the Gulf Stream changes, proponents of the theory were
overestimating the dependence of Europe on Gulf Stream warming.

Non-warming Effects of CO2

Interestingly, we may eventually decide that other
non-climate effects of CO2 production actually present more tangible
environmental threats.  In particular, recent studies have shown that more
atmospheric CO2 is causing the PH of ocean surface layers to drop (ie become
more acidic) leading potentially to coral kills and substantial changes in sea
life.  At the same time, physicist Freeman Dyson argues that stratospheric
cooling from man-made CO2 is much more a problem than surface warming, and is
much more measurable and provable.  These topics are beyond my scope at
this point, but something we may see more of in the future.

The table of contents for the rest of this paper, . 4A Layman's Guide to Anthropogenic Global Warming (AGW) is here.  Free pdf of this Climate Skepticism paper is here and print version is sold at cost here

The open comment thread for this paper can be found here. 

The table of contents for the rest of this paper, . 4A Layman's Guide to Anthropogenic Global Warming (AGW) is here.  Free pdf of this Climate Skepticism paper is here and print version is sold at cost here

As stated in the introduction, the purpose of this paper has
not been to provide a balanced portrayal of Anthropogenic Global Warming (AGW) theory; its purpose instead is to
provide a comprehensive overview of skeptic's concerns with AGW theory.
However, the issues raised here are not necessarily new, and AGW supporters
have attempted to address many of them. 

The New
Scientist, a fairly strong and reliable voice for advocacy of anthropogenic
global warming theory, recently published its response to what it calls 26
myths about global warming, many of these "myths" being correlated loosely with
skeptics concerns about AGW theory as outlined in this paper.  Walking
through their points seems a reasonable way to entertain a rebuttal to the
skeptic's position.  Each of these has a link to the New Scientist article
in question.  I have tried to summarize the position with a quote, shown
in italics.  My response to each then follows.

Before I get into these 20 myths, note that many of the key
skeptic's questions are neatly avoided.   While the magazine gives
itself certain softball questions, it does not attempt to take on skeptics
questions such as:

• Isn't warming from CO2 a diminishing return, such that each 10ppm of CO2
  has less warming effect than the last 10 ppm?
• Isn't warming from CO2 asymptotic, such that total warming from CO2 is
  capped?
• Isn't 2/3 or more of the future warming in IPCC forecasts due to
  positive feedback effects that tend to be rare in stable systems and that even
  the IPCC admits are poorly understood?
• Aren't there a lot of problems with ground-based temperature measurements?
• Aren't the historical proxies for temperature diverging from
  measurements, such that the IPCC actually dropped many of the recent proxy
  measurements to hide this result?

There are many others, but we can get at them tangentially
through dealing with the 20 "myths" below

"¢ Human
CO₂ emissions are too tiny to matter

So what's going on? It is true that human
emissions of CO₂ are small compared with natural sources. But the
fact that CO₂ levels have remained steady until very recently shows
that natural emissions are usually balanced by natural absorptions. Now
slightly more CO₂ must be entering the atmosphere than is being
soaked up by carbon "sinks".

Though I do know that some skeptics will claim that man can't be changing
world CO2 levels, I don't believe I even tried to make that claim in this paper.

The more salient point in
asking whether human CO2 emissions are too tiny to matter is to ask whether the
change in composition of the atmosphere of 0.009% by human activities is
substantial enough to affect world climate in any important way, particularly
when the portion being increased, CO2, is a relatively weak greenhouse gas vs.
other portions.

"¢ We
can't do anything about climate change

It is true that the action taken
so far, such as the Kyoto Protocol, will only have a marginal effect. The
protocol's authors have always described it as a first step. But even before it
came into effect in 2005, the protocol has triggered some profound thinking
among governments, corporations and citizens about their carbon footprint and
how to reduce it. Industrialized countries such as the UK are planning for
emissions reductions of 60% or more by mid-century.

This is a bit of a straw man.  Certainly to the extent
that man is causing climate change, men with enough will can do something about
it.  The question is whether the costs justify the avoided change "“ this
is a question that I have addressed sufficiently and won't revisit here.
However, I would like to comment on this:

We may find that once the
process has begun, the world loses its addiction to carbon fuels surprisingly quickly.
Natural scientists fear "tipping points" in the climate system. But there are
also tipping points in social, economic and political systems. Once under way,
things can happen fast"¦

This is a statement to which I both agree and disagree.  I am a technological
optimist, and so generally accept that world-changing technologies will
continue to spring from man's mind, and that the introduction of these changes
can be fast and their impact dramatic.  The only reason that I am a tad
skeptical about this statement is that the vast majority of strong AGW
adherents are technology pessimists, so it would be uncharacteristic for them
to take such a position.  Absent unimagined new technologies, change of
the type AGW supporters are hoping for is actually not a positive
feedback process as implied in this statement. Why is it that climate
scientists see so many positive feedback processes, when these are actually so
rare? In fact, most investment decisions, for example investments to reduce CO2
emissions, follow a diminishing return relationship.  Early investors
capture the low-hanging fruit, while each successive wave of investment offers
a lower return (here, in CO2 reduction) for each incremental dollar invested.

"¢ The
'hockey stick' graph has been proven wrong

Most researchers would agree that while the
original hockey stick can "“ and has "“ been improved in a number of ways, it was
not far off the mark. Most later temperature reconstructions fall within the
error bars of the original hockey stick. Some show far more variability leading
up to the 20^th century than the hockey stick, but none suggest that
it has been warmer at any time in the past 1000 years than in the last part of
the 20^th century.

No one statement by AGW supporters would do more to build my confidence in
their findings than to actually have someone say "the Mann hockey stick was a
deeply flawed analysis, and we have taken great pains to make sure the flaws identified
in Mann are not present in other historical reconstructions."  However,
when I see the statement above, I am left to wonder if any of the flaws in Mann
have actually been corrected in other works, or if systematic errors still
exist.  Since AGW supporters refuse to acknowledge flaws in Mann, it is
almost certain that these flaws still exist in the other analyses (therefore
making it unsurprising that new analyses show roughly the same results).
Remember that Mann was replaced by Biffra as lead author of this section of the
Fourth IPCC report, and it was Biffra who dropped 20-30 years of recent data
from his historical reconstruction when it did not show the result that he
wanted it to.

"¢ Chaotic
systems are not predictable

Getting reasonably accurate
predictions is a matter of choosing the right timescale: days in the case of
weather, decades in the case of climate.

Climate scientists sometimes
refer to the effects of chaos as intrinsic or unforced variability: the
unpredictable changes that arise from the dynamic interactions between the
oceans and atmosphere rather than being a result of "forcings" such
as changes in solar irradiance or greenhouse gases.

The crucial point is that
unforced variability occurs within a relatively narrow range. It is constrained
by the major factors influencing climate: it might make some winters bit a
warmer, for instance, but it cannot make winters warmer than summers

There are systems people who would both agree and disagree
with this statement.  The real study of chaotic systems is barely older
than the study of global warming, and most mathematicians would say that the
issue of long-term predictability of macro trends in chaotic systems is not
settled science.

However, one issue the statement overlooks is that even if
chaotic systems have some long-term order, at least when "viewed from a
distance," this does not mean that the drivers of those long-term trends can be
discerned by those of us standing in the chaos.  So while it may be
theoretically possible to predict long-scale climate changes, it may still be
impossible to discern the true drivers of these climate systems amidst the
chaos, making the long-term prediction problem moot.

Remember, no one has a thermometer that provides two readings "“ temperature
due to "natural" causes and temperature due to man-made forcings. 
The only argument one can make outside of a laboratory is to try to correlate
temperature changes to certain other variables, like CO2 level.  But in a
chaotic system, when thousands of variables may matter, and there are all kinds
of cross-dependencies between variables, definitively showing direct
correlation, much less causation, is very hard, possibly impossible. 
Remember, outside lab experiments, climate scientists main argument that CO2 is
causing current warming is "We have checked everything else it possibly could
be, and it wasn't those things, so it must be CO2."  In a chaotic system,
such a statement borders on hubris.

"¢ We
can't trust computer models of climate

Climate is average weather, and it can vary unpredictably
only within the limits set by major influences like the Sun and levels of
greenhouse gases in the atmosphere. We might not be able to say whether it will
rain at noon in a week's time, but we can be confident that the summers will be
hotter than winters for as long as the Earth's axis remains tilted.

The validity of models can be tested against
climate history. If they can predict the past (which the best models are pretty
good at) they are probably on the right track for predicting the future "“ and
indeed have successfully done so.

I hope that if you have learned anything from this paper, you already know
how to refute the statement above.  Climate models match history because
they have been tuned and tweaked and overridden to do so.  The fact that
they then can reproduce history is meaningless.  Even more, you should run
away quickly from anyone who makes this statement, because they are either
ignorant of what they are talking about or they are trying to sell you the
Brooklyn Bridge.

Finally, the claim is sometimes
made that if computer models were any good, people would be using them to
predict the stock market. Well, they are!

A lot of trading in the
financial markets is already carried out by computers. Many base their
decisions on fairly simple algorithms designed to exploit tiny profit margins,
but others rely on more sophisticated long-term models.

Sorry, but this is a facile and ignorant mis-interpretation of what
financial models are doing.  Yes, people are running long-term financial
models as part of a trading strategy, but these models feed into very
short-term trading decisions.  If you looked at the output from these long-term
models, you would see that they are changing constantly as new data flows
in.  There is an old joke about two campers who see a bear growling at
them.  One of them starts putting his tennis shoes on.  The other one
says to him "Why are you putting your shoes on?  You can't outrun that
bear."   His friend replied "I don't have to outrun the bear.  I
just have to outrun you."  Traders' long-term models work the same.
They don't actually expect them to be right, they just want them to be better,
based on current conditions, than other traders' models, then they can make
money.

"¢ They
predicted global cooling in the 1970s

Indeed they did"¦. However, Schneider soon
realised he had overestimated the cooling effect of aerosol pollution and
underestimated the effect of CO₂, meaning warming was more likely
than cooling in the long run"¦.

The calls for action to prevent further
human-induced global warming, by contrast, are based on an enormous body of
research by thousands of scientists over more than a century that has been
subjected to intense "“ and sometimes ferocious "“ scrutiny. According to the
latest IPCC report, it is more than
90% certain that the world is already warming as a result of human activity

We have already dealt with aerosols, and unlike many skeptics I have not
really held the 1970's global cooling panic against the climate
community.  The last paragraph is just circular.  Saying the IPCC is
90% sure does not answer the arguments about what skeptics feel the IPCC is
ignoring.

"¢ It's
been far warmer in the past, what's the big deal?

First of all, it is worth bearing in mind that
any data on global temperatures before about 150 years ago is an estimate, a
reconstruction based on second-hand evidence such as ice cores and isotopic
ratios. The evidence becomes sparser the further back we look, and its
interpretation often involves a set of assumptions. In other words, a fair
amount of guesswork.

This is hilarious.  What happened to their confidence in Mann and
1000-year temperature reconstructions just a few myths back?  But to
continue, the answer is basically yes, but:

The important question is what
is causing the current, rapid warming? We cannot dismiss it as natural
variation just because the planet has been warmer at various times in the past.
Many studies suggest it can only be explained by taking into account human
activity.

Nor does the fact that it has
been warmer in the past mean that future warming is nothing to worry about. The
sea level has been tens of metres higher during past warm periods, enough to
submerge most major cities around the world.

Here is why it matters "“ beyond the laboratory evidence of the greenhouse
effect, which tells us merely that there is an affect and not how strong it is,
the main evidence cited by AGW supporters for current warming being man-made is
to try to show that current warming is somehow unprecedented, and therefore
unlikely to be natural.  So it is odd here that AGW supporters simply
shrug their shoulders here and say that it is not important that current
warming be unprecedented.

"¢ It's
too cold where I live - warming will be great

This does not sound too bad, and for many people
it won't be. Wealthy individuals and countries will be able to adapt to most
short-term changes, whether it means buying an air conditioner or switching to
crops better suited to the changing climate. Rainfall will fall in
mid-latitudes but rise in high latitudes, and initially agricultural yields
will probably.  Some regions will suffer, though. Africa could be hardest
hit, with yields predicted to halve in some countries as early as 2020.

As global temperature climbs to 3°C above
present levels - which is likely
to happen before the end of this century if greenhouse emissions continue
unabated - the consequences will become increasingly severe. More than a third
of species face extinction. Agricultural yields will start to fall in many
parts of the world. Millions of people will be at risk from coastal flooding.
Heatwaves, droughts, floods and wildfires will take an ever greater toll.

I hope readers will accept that I am not exaggerating or constructing straw
men when I talk about the dire predictions by AGW supporters.  There is
nothing here that we have not dealt with earlier, except perhaps the
rainfall.  Of late, AGW supporters seem to have shifted to rainfall
(rather than sea level rise) as their lead scary topic.  Note, however,
that even the IPCC admits that it and all of its modelers really do not
understand (even a little bit) the effect of global warming on rainfall and
drought.  Logic says that with more water evaporated, while global warming
may cause now local draughts, overall rainfall should increase.  I would
bet any amount of money that lower economic growth due to aggressive CO2 abatement
will have a far more deleterious effect on worldwide agricultural yields than
global warming.

"¢ Global
warming is down to the Sun, not humans

So what role, if any, have solar fluctuations
had in recent temperature changes? While we can work out how Earth's orbit has
changed going back many millions of years, we have no first-hand record of the
changes in solar output associated with sunspots before the 20^th century.

It is true that sunspot records go back to the
17^th century, but sunspots actually block the Sun's radiation. It is
the smaller bright spots (faculae) that increase the Sun's output and these
were not recorded until more recently. The correlation between sunspots and
bright faculae is not perfect, so estimates of solar activity based on sunspot
records may be out by as much as 30%.

The other method of working out past solar
activity is to measure levels of carbon-14 and beryllium-10 in tree rings and
ice cores. These isotopes are formed when cosmic rays hit the atmosphere, and
higher sunspot activity is associated with increases in the solar wind that
deflect more galactic cosmic rays away from Earth. Yet again, though, the
correlation is not perfect. What is more, recent evidence suggests that the
deposition of beryllium-10 can
be affected by climate changes, making it even less reliable as a measure
of past solar activity.

This is again a pretty hilarious statement.  One could easily argue
that temperature and CO2 proxies have at least as much
uncertainty.  One wonders why AGW advocates do not seem as concerned about
the errors in the proxies they hold dear.  But anyway, to continue:

But even if solar forcing in the past was more
important than this estimate suggests, as some scientists think, there is no
correlation between solar activity and the strong warming during the past 40
years. Claims that this is the case have not stood up to scrutiny (pdf document).

Direct measurements of solar output since 1978
show a steady rise and fall over the 11-year sunspot cycle, but no upwards or downward trend .

Similarly, there is no trend in direct
measurements of the Sun's ultraviolet output and in cosmic rays. So for the
period for which we have direct, reliable records, the Earth has warmed
dramatically even though there has been no corresponding rise in any kind of
solar activity.

This is another you-study-my-study pissing match.  I am happy to admit
that our knowledge of the sun's changing impact on climate is poor, and that it
is hard to separate out this one effect in a chaotic system.  I refuse to
fall into the same scientific hubris as AGW supporters.  However, those
who think the sun has some contribution to warming are buttressed by the
knowledge that they are working with the main driver of climate, rather than a
secondary variable.

"¢ It's
all down to cosmic rays

There is no convincing evidence
that cosmic rays are a major factor determining cloud cover. The ionising of
air by cosmic rays will impart an electric charge to aerosols, which in theory
could encourage them to clump together to form particles large enough for cloud
droplets to form around, called "cloud condensation nuclei".

But cloud physicists say it has
yet to be shown that such clumping occurs. And even if it does, it seems
far-fetched to expect any great effect on the amount of clouds in the atmosphere.
Most of the atmosphere, even relatively clean marine air, has plenty of cloud
condensation nuclei already.

A series of attempts by
Svensmark to show an effect have come unstuck. Initially, Svensmark claimed
there was a correlation between cosmic ray intensity and satellite measurements
of total cloud cover since the 1980s "“ yet a correlation does not prove cause
and effect. It could equally well reflect changes in solar irradiance, which
inversely correlate with cosmic ray intensity.

I am starting to notice a trend here of making statements about competing
that could be applied equally well to AGW theory.  And what about all
those points they made above, reminding us over and over that CO2 greenhouse
theory works in the lab.  Now the lab is not good enough?

However, I would accept that the cosmic ray theory is pretty undeveloped and
not acceptably proven.  It has had a number of fits and starts.  Just
like CO2 greenhouse theory, the cosmic ray effect on climate can be reproduced
in the lab, but it is really hard to parse out its effects in the chaotic
climate.

"¢ CO₂
isn't the most important greenhouse gas

At some of these overlaps, the
atmosphere already absorbs 100% of radiation, meaning that adding more
greenhouse gases cannot increase absorption at these specific frequencies. For
other frequencies, only a small proportion is currently absorbed, so higher
levels of greenhouse gases do make a difference.

This means that when it comes to
the greenhouse effect, two plus two does not equal four.

Wow!  An AGW supporter actually said this in public.  This is to
our point that there is a diminishing return from incremental CO2 in the
atmosphere.  Of course, they say this in the context of trying to show why
water isn't as important as it might seem, but still, it's there

But the overall quantities of these other gases
are tiny. Even allowing for the relative strength of the effects, CO₂
is still responsible for two-thirds
of the additional warming caused by all the greenhouse gases emitted as a
result of human activity.

Water vapour will play a huge role in the
centuries to come, though. Climate models, backed by satellite
measurements, suggest that the amount of water vapour in the upper
troposphere (about 5 to 10 kilometres up) will double by the end of this
century as temperatures rise.

This will result in roughly twice as much
warming than if water vapour remained constant. Changes in clouds could lead to
even greater amplification of the warming or reduce it "“ there is great uncertainty
about this. What is certain is that, in the jargon of climate science, water
vapour is a feedback, but not a forcing.

Again, I am not getting into this, we covered it plenty in the paper.
When they say "CO2 is still responsible for two-thirds of the additional
warming" (and remember this is an output of their models, not any other
analysis)  what they really mean is that "our models that were programmed
to have CO2 drive the climate show that CO2 drives the climate."
Note that in a three paragraph answer about the effect of water vapor as
a climate feedback, only three words "“ "or reduce it" "“ acknowledge that it
might actually have a negative feedback effect, despite the fact that even the
IPCC includes cloud cover as a negative feedback.  They just don't want to
admit a negative feedback might even exist.

"¢ The
lower atmosphere is cooling, not warming

One study in Science
revealed errors in the way satellite data had been collected and interpreted.
For instance, the orbit of satellites gradually slows, which has to be taken
into account because it affects the time of day at which temperature recording
are taken. This problem was always recognised, but the corrections were given
the wrong sign (negative instead positive and vice versa).

A second study, also
in Science, looked at the weather balloon data. Measurements of the air
temperature during the day can be skewed if the instruments are heated by
sunlight. Over the years the makers of weather balloons had come up with better
methods of preventing or correcting for this effect, but because no one had
taken these improvements into account, the more accurate measurements appeared
to show daytime temperatures getting cooler.

The corrected temperature records show that
tropospheric temperatures are indeed rising at roughly the same rate as surface
temperatures. Or, as a 2006 report by the US Climate Change Science Program (pdf) puts
it: "For recent decades, all current atmospheric data sets now show
global-average warming that is similar to the surface warming." This one
appears settled.

There is still some ambiguity in the tropics,
where most measurements show the surface warming faster than the upper
troposphere, whereas the models predict faster warming of the atmosphere.
However, this is a minor discrepancy compared with cooling of the entire
troposphere and could just be due to the errors of margin inherent in both the
observations and the models.

First, observe absolutely ruthless efforts to apply corrections and
adjustments to any measurement that does not fit their theory, while blithely
accepting the surface temperature measurements that we showed can be really
unreliable.  Given the choice of focusing on managing satellite
temperatures up or surface temperature down, you can see which they
chose.   Second, note that this is another narrow one study
conclusion.  AGW supporters frequently cite single studies (conducted by
AGW supporters) that overturn skeptics arguments as having "settled" the
issue.  There are still many reasons to think that troposphere temperature
increases are less than surface increases.  Finally, even temperature
increases that were the same between the surface and the troposphere would be a
real problem for AGW theory.  The authors here act like this
surface-troposphere issue is a minor deal, but in fact if AGW theory is right,
the troposphere has to warm more, because that is where the extra heat
is being absorbed.  This is not at all settled. 

"¢ Antarctica
is getting cooler, not warmer, disproving global warming

It is clear that the Antarctic Peninsula, which juts
out from the mainland of Antarctica towards South America, has warmed
significantly. The continent's interior was thought to have warmed too, but in
2002 a new analysis of
records from 1966 to 2000 concluded that it has cooled overall"¦.

Climate models do not predict an evenly spread
warming of the whole planet: changes in wind patterns and ocean currents can
change the distribution of heat, leading to some parts warming much faster than
average, while others cool at first.

Agreed

"¢ The
oceans are cooling

Now the authors of the 2006 study have submitted a
correction (pdf format). It turns out that a fault in the software on some
of the floats led to some temperature measurements being associated with the
wrong depth.

Meanwhile, work by other teams suggests that the
past warmth of the oceans has been overestimated. The problem was due to
expendable sensors that are thrown overboard and take measurements as they
sink.

I never had heard the claim that the oceans were cooling, so it does not
surprise me that they are not.  However, it is again interesting the
amount of due diligence that AGW supporter put in to the correction of any
temperature measurement the might refute global warming, while blithely
accepting the atrocious condition and biases in ground-based temperature
measurement because, well, because these instruments are telling the story they
want to hear.

"¢ The
cooling after 1940 shows CO₂ does not cause warming

The mid-century cooling appears to have been
largely due to a high concentration of sulphate aerosols in the atmosphere,
emitted by industrial activities and volcanic
eruptions. Sulphate aerosols have a cooling effect on the climate because
they scatter light from the Sun, reflecting its
energy back out into space.

The rise in sulphate aerosols was largely due to
the increase in industrial activities at the end of the second world war. In
addition, the large eruption of Mount Agung in 1963 produced aerosols which cooled the
lower atmosphere by about 0.5°C, while solar activity levelled off after
increasing at the beginning of the century

I think I was pretty fair in discussing the aerosol cooling hypothesis in
this paper, though many would disagree with the above statement's certainty.

Climate models that take into account only
natural factors, such as solar activity and volcanic eruptions, do not
reproduce 20th century temperatures very well. If, however, the models include
human emissions, including greenhouse gases and aerosols, they accurately reproduce
the 1940 to 1970 dip in temperatures.

I hope readers who have made it this far can supply the refutation of this
point:  Wrong, wrong, wrong.  Climate models initially matched
history poorly.  Today they match well because they have been tweaked and
adjusted and forced to match.  They match because they are programmed to
match.  And, as we discussed, they match only because they make
ridiculously low assumptions for natural forcings, and assume all natural
forcings causing temperatures to rise in the first half of the century
magically reversed in 1950, though there is no good evidence for it. 

"¢ It
was warmer during the Medieval period, with vineyards in England

In the southern hemisphere, the picture is even
more mixed, with evidence of both warm and cool periods around this time. The
Medieval Warm Period may have been partly a regional phenomenon, with the
extremes reflecting a redistribution of heat around the planet rather than a
big overall rise in the average global temperature.

What is clear, both from the temperature
reconstructions and from independent evidence "“ such as the extent of the
recent melting of mountain glaciers "“ is that the planet has been warmer in the
past few decades than at any time during the medieval period. In fact, the
world may not have been so warm for 6000 or even 125,000 years (see Climate myths: It has been warmer in the past,
what's the big deal?).

What really matters, though, is not how warm it
is now, but how warm it is going to get in the future. Even the temperature
reconstructions that show the greatest variations in the past 1000 years suggest
up until the 1980s, average temperature changes remained within a narrow band
spanning 1ºC at most. Now we are climbing out of that band, and the latest IPCC report (pdf format) predicts a further rise of
0.5ºC by 2030 and a whopping 6.4ºC by 2100 in the worst case scenario.

We have covered this pretty well in this paper, so again I won't go back
into it, except to highlight a couple of things we can learn from this
statement.  First, note the hubris again "“ it is warmer today than in the
last 125,000 years.  I sure wish there was a way to bet on this "“ I would
have only a one in 125,000 chance of being wrong in betting against this
statement.  Second, note the use of the worst case scenarios.  For
2100, we don't get the best case or even the average case, we get the worst
case.  Can you name another branch of science where people do this?
Can you imagine, say, a group out to measure the speed of light.  They are
going to get some middle figure with an error band of some range.
Wouldn't you expect them to day that they found the speed of light to be
so-and-so, plus or minus an error of such-and-such size?  If they were
climate scientists, they would instead announce that they have found the speed
of light could be as large as Z, that being the highest possible figure in
their error band.

"¢ We
are simply recovering from the Little Ice Age

Yet while there is some evidence of cold
intervals in parts of the southern hemisphere during this time, they do not appear to
coincide with those in the northern hemisphere. Such findings suggest the Little
Ice Age may have been more of a regional phenomenon than a global one.

Solar radiation was probably lower at times
during this period, especially during a dip in solar activity called the
Maunder minimum around 1700, but models and temperature reconstructions suggest
this would have reduced average global temperatures by 0.4ºC at most.

The larger falls in temperature in Europe and
North American may have been due to changes in atmospheric circulation over the
North Atlantic, or in the Gulf Stream, or both, reducing heat transport from
the tropics (see Climate
change sceptics lose vital argument).

The warming after the so-called Little Ice Age
may reflect both an increase in solar activity and a redistribution of heat
around the planet. In particular, the increase in global temperature in the
first half of the 20^th century may have been largely due to an increase
in solar activity. The continued warming in recent decades, however, cannot be
explained by increases in solar radiation alone

Remember the graphs we showed earlier "“ the arctic proxies look like the
current warming is a straight linear increase from the 1700s to today.  In
fact, in the IPCC spaghetti graph showing all those historic reconstructions,
they all show a natural warming from the 18^th and 19^th
century through the 20^th.  Again, AGW supporters really need to
explain why they are so confident that this natural warming trend stopped in
1945 or so, exactly and coincidently at the exact same moment that man-made
forcings caused the world to continue to warm, coincidently at about the same
rate it was warming naturally earlier in the century.

"¢ Warming
will cause an ice age in Europe

Few scientists think there will
be a rapid shutdown of circulation. Most ocean models predict no more than a
slowdown, probably towards the end of the century. This could slow or even
reverse some of the warming due to human emissions of greenhouse gases, which
might even be welcome in an overheated Europe, but the continent is not likely
to get colder than it is at present.

A slowdown in circulation would
affect many parts of the world by disrupting global rainfall patterns. But
these effects will be insignificant compared with the much greater changes
global warming will cause

I already mentioned that this had been refuted pretty well

"¢ Ice
cores show CO₂ increases lag behind temperature rises, disproving
the link to global warming

It takes about 5000 years for an
ice age to end and, after the initial 800 year lag, temperature and CO₂
concentrations in the atmosphere rise together for a further 4200 years.

What seems to have happened at
the end of the recent ice ages is that some factor "“ most probably orbital
changes "“ caused a rise in temperature. This led to an increase in CO₂,
resulting in further warming that caused more CO₂ to be released and
so on: a positive feedback that amplified a small change in temperature. At
some point, the shrinking of the ice sheets further amplified the warming.

Models suggest that rising
greenhouse gases, including CO₂, explains about 40% of the warming
as the ice ages ended. The figure is uncertain because it depends on how the
extent of ice coverage changed over time, and there is no way to pin this down
precisely.

I was extremely happy to see that they at least tried to
address the issue I raised, ie is it really realistic to have a process
dominated by positive feedback, and if so, why doesn't it run away.  Their
answer:

Finally, if higher temperatures lead
to more CO₂ and more CO₂ leads to higher temperatures,
why doesn't this positive feedback lead to a runaway greenhouse effect? There
are various limiting factors that kick in, the most important being that
infrared radiation emitted by Earth increases exponentially with temperature,
so as long as some infrared can escape from the atmosphere, at some point heat
loss catches up with heat retention.

Which might make sense EXCEPT that they are claiming that
today's temperature and level of CO2 are higher than these historical levels,
so we are already higher than the level where they claim "heat loss catches up
with heat retention."  So either their answer is right, and there is a
strong compensating process which is not built into their models, or they are
wrong and they still need to explain what keeps a positive feedback dominated
process from running away.

"¢ Ice
cores show CO₂ rising as temperatures fell

There are some mismatches though. Besides lags
at the end of ice ages, cores taken from the ice overlying the famous
lake below Vostok in Antarctica seemed to show that about 120,000 years
ago, the temperature plummeted sharply while CO₂ levels remained high
for many thousands of years.

The question is whether this is real or just a
reflection of the problems with working out the age of the trapped air and with
deuterium as a temperature indicator. Many researchers are working on ways to
independently date the air and the ice, and to improve temperature
reconstructions based on relative deuterium content. One involves working out
what is called the deuterium excess by comparing the relative amounts of
deuterium and oxygen-18 in the ice.

The deuterium excess reflects the temperature at
the sea surface where the water that later fell as snow evaporated, rather than
the surface temperature where the snow fell. It helps to reveal whether
variations in the relative deuterium content of the ice are a result of water
coming from a different source region rather than changes in local temperature.

In 2001, researchers used the deuterium excess to correct for some of the
problems with the temperature record of the Vostok ice core. Their results produce
a much closer fit between temperature and CO₂ levels and reduces the
mismatch around 120,000 years ago to a few thousand years.

I did not really raise this issue, as even the most enthusiastic AGW
supporter does not tend to claim that CO2 drives all historic temperature
changes.  However, again, note the pattern "“ any historic data that does
not fit with AGW data typically is scrutinized and "corrected." 
Articles discussing flaws in methodology in gathering such data are quickly published.
Contrast this with the difficulty scientists have in questioning any data that
supports AGW theory.  As we saw earlier, the New Scientist still can't
bring itself to utter the words "the Mann hockey stick was flawed."
Neither could the IPCC, they just sort of dropped it, or buried it in the midst
of 12 others, without even saying why the analysis that was the centerpiece of
their last report was strangely missing.

"¢ Mars
and Pluto are warming too

The Sun's energy output has not increased since
direct measurements began in 1978. If increased solar output really was
responsible, we should be seeing warming on all the planets and their moons,
not just Mars and Pluto.

Our solar system has eight planets, three dwarf
planets and quite a few moons with at least a rudimentary atmosphere, and thus
a climate of sorts. Their climates will be affected by local factors such as
orbital variations, changes in reflectance (albedo) and even volcanic
eruptions, so it would not be surprising if several planets and moons turn out
to be warming at any one time.

I agree we have a lot to learn about this, and nothing at all is
settled.  However, we now have evidence from at least 5 other terrestrial bodies
that are warming at the same time the Earth is warming.  Why do AGW
supporters resist at least investigating further?

"¢ Many
leading scientists question climate change

Climate change sceptics sometimes claim that
many leading scientists question climate change. Well, it all depends on what
you mean by "many" and "leading". For instance, in April
2006, 60 "leading scientists" signed a letter urging Canada's
new prime minister to review his country's commitment to the Kyoto protocol.

This appears to be the biggest recent list of
sceptics. Yet many, if not most, of the 60 signatories are not actively engaged
in studying climate change: some are not scientists at all and at least 15 are
retired.

Compare that with the dozens of statements on
climate change from various scientific organisations around the world
representing tens of thousands of scientists, the consensus position
represented by the IPCC reports and the 11,000 signatories to a petition condemning the Bush administration's
stance on climate science.

I have carefully avoided the game of dueling scientific numbers.  As to
the claim that the skeptic list "are not actively engaged in studying
climate change: some are not scientists at all and at least 15 are retired" I
would be thrilled if AGW supporters held to this standard in making their own
numbers.  But, they manage to abandon this standard by the next paragraph,
when they claim the pro-AGW numbers, like the 11,000, are open to the same
criticism (since there are only 500-600 true climate scientists in the world,
vs. physicist, meteorologists, etc). 

"¢ It's
all a conspiracy

Now that there is a consensus, those whose
findings challenge the orthodoxy are always going have a tougher time
convincing their peers, as in any field of science. For this reason, there will
inevitably be pressure on scientists who challenge the consensus. But findings
or ideas that clash with the idea of human-induced global warming have not been
suppressed or ignored "“ far from it.

Journalists do have an interest in promoting
themselves (and their books), while their employers want to boost their
audience and sell advertising. Publicity helps with all these aims, but you get
far more publicity by challenging the mainstream view than by promoting it.
Which helps explain why so many sections of the media continue to publish or
broadcast the claims of deniers, regardless of their merit.

The notion of a "conspiracy" of course, is a useful straw man, implying
devious villains in the SPECTRE conference room planning the overthrow of the
world.   I won't argue the point again, except to encourage you to
watch the news with a critical eye, and decide for yourself.  However, just
to get you started, ask yourself if these events are signs of healthy, unbiased
science:

· A
group of AGW supporters are trying to get the British government to use force
to block the publication of a skeptical movie (the Global Warming Swindle)

· AGW
supporters in California have included skeptical scientists such as MIT's Dr.
Richard Lindzen as defendants in a law suit, asking that damages be paid by
people and companies whose public speech doesn't conform to AGW theory

· Many
AGW skeptics have been unable to get scientists who have published publicly
funded research to reveal their data and methodology for critique.
Freedom of Information Act (FOIA) requests have become a necessary tool of
climate skeptics.

· When
a group began photographing temperature measurement points to document the
shortcomings in historical surface temperature measurements, the NOAA pulled
the locations of its measurement stations off the Internet so that these US
citizens could no longer take pictures of and critique US government
installations.

· Scientists
who question AGW theory are equated by AGW supporters with Holocaust deniers.

"¢ Hurricane
Katrina was caused by global warming

More data is needed settle the issue. Some are
looking to natural records of past
hurricane activity in stalagmites, lake deposits and coral rubble. Others
are re-analysing existing databases. In February 2007, one such re-analysis
concluded that over the past two decades, hurricane intensity has increased
in the Atlantic but not in other parts of the world (pdf format).

Yet another complicating factor is that changes
in climate can also change the paths that tropical cyclones tend to take,
determining whether they remain over oceans or strike land.

What every one agrees on is that over the past
few decades there has been a huge rise in the number of people being killed or
injured by hurricanes, and in damage to infrastructure, and this trend looks
set to continue. The main reason for this, however, is that more and more
people are living and building in hurricane zones.

Most of these three paragraphs is entirely correct "“ there is no evidence
that hurricane numbers or intensity are effected by global warming, and if they
are, whether they are increased or decreased.  However, Hurricane Katrina
was most certainly NOT caused by global warming.  Why can't they just say
that?   It may have been made stronger or weaker.  Its course
may have been altered.   But it was not created by warming.  By
the way, the year after Katrina saw a much smaller than average Atlantic
hurricane season.

"¢ Higher
CO₂ levels will boost plant growth and food production

But it is extremely difficult to generalise
about the overall impact on plant growth. Numerous groups around the world have
been conducting experiments in which plots of land
are supplied with enhanced CO₂, while comparable nearby plots remain
at normal levels.

While these experiments typically have found
initial elevations in the rate of plant growth, these have tended to level off
within a few years. In most cases this has been found to be the result of some
other limiting factor, such as the availability of nitrogen or water.

So the answer is yes, but there is a diminishing return at some point.
Isn't that the same as can be said for the CO2 greenhouse effect?

Predicting the world's overall changes in food
production in response to elevated CO₂ is virtually impossible.
Global production is expected to rise until the increase in local average
temperatures exceeds 3°C, but then start to fall. In tropical and dry regions
increases of just 1 to 2°C are expected to lead to falls in production. In
marginal lands where water is the greatest constraint, which includes much of
the developing world but also regions such as the western US, the losses may
greatly exceed the gains.

Have you noticed yet that things that might hurt the AGW-interventionist's
case always seem "impossible to predict" while the climate is well within our
prediction capabilities?

As for food crops, the factors are more complex.
The crops most widely used in the world for food in many cases depend on
particular combinations of soil type, climate, moisture, weather patterns and
the infrastructure of equipment, experience and distribution systems. If the
climate warms so much that crops no longer thrive in their traditional settings,
farming of some crops may be able to shift to adjacent areas, but others may
not. Rich farmers and countries will be able to adapt more easily than poorer
ones.

I love the rich-poor language.  The leftish New Scientist simply can't
help itself.  But I will accept this statement, and go further:  This
is the reason that aggressive actions to reduce CO2 that reduce economic
growth, particularly in the developing world, may not make sense.  To the
extent that some climate change will occur no matter what, or is already
programmed by our past actions, then a richer world can deal with it better
than a poorer one.

"¢ Polar
bear numbers are increasing

Yet recently there have been
claims that polar bear populations are increasing. So what's going on? There
are thought to be between 20,000 and 25,000 polar bears in 19 population groups
around the Arctic. While polar bear numbers are increasing in two of these
populations, two others are definitely in decline. We don't really know how the
rest of the populations are faring, so the truth is that no one can say for
sure how overall numbers are changing.

Again, I love this.  We can know the global temperature
increase over a century to a tenth of a degree but it is impossible to count
polar bears.

A comprehensive review (pdf) by the US Fish and Wildlife Service
concluded that shrinking sea ice is the primary cause for the decline seen in
these populations, and it recently proposed listing
polar bears as threatened (pdf) under the Endangered Species Act. The
International Conservation Union projects the bears' numbers will drop by 30% by 2050
(pdf) due to continued loss of Arctic sea ice.

Note that down 30% (which coming from an environmental
advocacy ground has got to be considered the most extreme possible estimate) is
not "extinct."  The article fails to address at all the issue that polar
bears have survived through eras when Arctic sea ice melted completely in the
summers.  And there are many reasons for threats to polar bear numbers "“
most experts would say that hunting and threats to habitat are much more
important factors than global temperatures.

The table of contents for the rest of this paper, . 4A Layman's Guide to Anthropogenic Global Warming (AGW) is here.  Free pdf of this Climate Skepticism paper is here and print version is sold at cost here

The open comment thread for this paper can be found here. 

The table of contents for the rest of this paper, . 4A Layman's Guide to Anthropogenic Global Warming (AGW) is here.  Free pdf of this Climate Skepticism paper is here and print version is sold at cost here

As stated in the introduction, the purpose of this paper has
not been to provide a balanced portrayal of Anthropogenic Global Warming (AGW) theory; its purpose instead is to
provide a comprehensive overview of skeptic's concerns with AGW theory.
However, the issues raised here are not necessarily new, and AGW supporters
have attempted to address many of them. 

The New
Scientist, a fairly strong and reliable voice for advocacy of anthropogenic
global warming theory, recently published its response to what it calls 26
myths about global warming, many of these "myths" being correlated loosely with
skeptics concerns about AGW theory as outlined in this paper.  Walking
through their points seems a reasonable way to entertain a rebuttal to the
skeptic's position.  Each of these has a link to the New Scientist article
in question.  I have tried to summarize the position with a quote, shown
in italics.  My response to each then follows.

Before I get into these 20 myths, note that many of the key
skeptic's questions are neatly avoided.   While the magazine gives
itself certain softball questions, it does not attempt to take on skeptics
questions such as:

• Isn't warming from CO2 a diminishing return, such that each 10ppm of CO2
  has less warming effect than the last 10 ppm?
• Isn't warming from CO2 asymptotic, such that total warming from CO2 is
  capped?
• Isn't 2/3 or more of the future warming in IPCC forecasts due to
  positive feedback effects that tend to be rare in stable systems and that even
  the IPCC admits are poorly understood?
• Aren't there a lot of problems with ground-based temperature measurements?
• Aren't the historical proxies for temperature diverging from
  measurements, such that the IPCC actually dropped many of the recent proxy
  measurements to hide this result?

There are many others, but we can get at them tangentially
through dealing with the 20 "myths" below

"¢ Human
CO₂ emissions are too tiny to matter

So what's going on? It is true that human
emissions of CO₂ are small compared with natural sources. But the
fact that CO₂ levels have remained steady until very recently shows
that natural emissions are usually balanced by natural absorptions. Now
slightly more CO₂ must be entering the atmosphere than is being
soaked up by carbon "sinks".

Though I do know that some skeptics will claim that man can't be changing
world CO2 levels, I don't believe I even tried to make that claim in this paper.

The more salient point in
asking whether human CO2 emissions are too tiny to matter is to ask whether the
change in composition of the atmosphere of 0.009% by human activities is
substantial enough to affect world climate in any important way, particularly
when the portion being increased, CO2, is a relatively weak greenhouse gas vs.
other portions.

"¢ We
can't do anything about climate change

It is true that the action taken
so far, such as the Kyoto Protocol, will only have a marginal effect. The
protocol's authors have always described it as a first step. But even before it
came into effect in 2005, the protocol has triggered some profound thinking
among governments, corporations and citizens about their carbon footprint and
how to reduce it. Industrialized countries such as the UK are planning for
emissions reductions of 60% or more by mid-century.

This is a bit of a straw man.  Certainly to the extent
that man is causing climate change, men with enough will can do something about
it.  The question is whether the costs justify the avoided change "“ this
is a question that I have addressed sufficiently and won't revisit here.
However, I would like to comment on this:

We may find that once the
process has begun, the world loses its addiction to carbon fuels surprisingly quickly.
Natural scientists fear "tipping points" in the climate system. But there are
also tipping points in social, economic and political systems. Once under way,
things can happen fast"¦

This is a statement to which I both agree and disagree.  I am a technological
optimist, and so generally accept that world-changing technologies will
continue to spring from man's mind, and that the introduction of these changes
can be fast and their impact dramatic.  The only reason that I am a tad
skeptical about this statement is that the vast majority of strong AGW
adherents are technology pessimists, so it would be uncharacteristic for them
to take such a position.  Absent unimagined new technologies, change of
the type AGW supporters are hoping for is actually not a positive
feedback process as implied in this statement. Why is it that climate
scientists see so many positive feedback processes, when these are actually so
rare? In fact, most investment decisions, for example investments to reduce CO2
emissions, follow a diminishing return relationship.  Early investors
capture the low-hanging fruit, while each successive wave of investment offers
a lower return (here, in CO2 reduction) for each incremental dollar invested.

"¢ The
'hockey stick' graph has been proven wrong

Most researchers would agree that while the
original hockey stick can "“ and has "“ been improved in a number of ways, it was
not far off the mark. Most later temperature reconstructions fall within the
error bars of the original hockey stick. Some show far more variability leading
up to the 20^th century than the hockey stick, but none suggest that
it has been warmer at any time in the past 1000 years than in the last part of
the 20^th century.

No one statement by AGW supporters would do more to build my confidence in
their findings than to actually have someone say "the Mann hockey stick was a
deeply flawed analysis, and we have taken great pains to make sure the flaws identified
in Mann are not present in other historical reconstructions."  However,
when I see the statement above, I am left to wonder if any of the flaws in Mann
have actually been corrected in other works, or if systematic errors still
exist.  Since AGW supporters refuse to acknowledge flaws in Mann, it is
almost certain that these flaws still exist in the other analyses (therefore
making it unsurprising that new analyses show roughly the same results).
Remember that Mann was replaced by Biffra as lead author of this section of the
Fourth IPCC report, and it was Biffra who dropped 20-30 years of recent data
from his historical reconstruction when it did not show the result that he
wanted it to.

"¢ Chaotic
systems are not predictable

Getting reasonably accurate
predictions is a matter of choosing the right timescale: days in the case of
weather, decades in the case of climate.

Climate scientists sometimes
refer to the effects of chaos as intrinsic or unforced variability: the
unpredictable changes that arise from the dynamic interactions between the
oceans and atmosphere rather than being a result of "forcings" such
as changes in solar irradiance or greenhouse gases.

The crucial point is that
unforced variability occurs within a relatively narrow range. It is constrained
by the major factors influencing climate: it might make some winters bit a
warmer, for instance, but it cannot make winters warmer than summers

There are systems people who would both agree and disagree
with this statement.  The real study of chaotic systems is barely older
than the study of global warming, and most mathematicians would say that the
issue of long-term predictability of macro trends in chaotic systems is not
settled science.

However, one issue the statement overlooks is that even if
chaotic systems have some long-term order, at least when "viewed from a
distance," this does not mean that the drivers of those long-term trends can be
discerned by those of us standing in the chaos.  So while it may be
theoretically possible to predict long-scale climate changes, it may still be
impossible to discern the true drivers of these climate systems amidst the
chaos, making the long-term prediction problem moot.

Remember, no one has a thermometer that provides two readings "“ temperature
due to "natural" causes and temperature due to man-made forcings. 
The only argument one can make outside of a laboratory is to try to correlate
temperature changes to certain other variables, like CO2 level.  But in a
chaotic system, when thousands of variables may matter, and there are all kinds
of cross-dependencies between variables, definitively showing direct
correlation, much less causation, is very hard, possibly impossible. 
Remember, outside lab experiments, climate scientists main argument that CO2 is
causing current warming is "We have checked everything else it possibly could
be, and it wasn't those things, so it must be CO2."  In a chaotic system,
such a statement borders on hubris.

"¢ We
can't trust computer models of climate

Climate is average weather, and it can vary unpredictably
only within the limits set by major influences like the Sun and levels of
greenhouse gases in the atmosphere. We might not be able to say whether it will
rain at noon in a week's time, but we can be confident that the summers will be
hotter than winters for as long as the Earth's axis remains tilted.

The validity of models can be tested against
climate history. If they can predict the past (which the best models are pretty
good at) they are probably on the right track for predicting the future "“ and
indeed have successfully done so.

I hope that if you have learned anything from this paper, you already know
how to refute the statement above.  Climate models match history because
they have been tuned and tweaked and overridden to do so.  The fact that
they then can reproduce history is meaningless.  Even more, you should run
away quickly from anyone who makes this statement, because they are either
ignorant of what they are talking about or they are trying to sell you the
Brooklyn Bridge.

Finally, the claim is sometimes
made that if computer models were any good, people would be using them to
predict the stock market. Well, they are!

A lot of trading in the
financial markets is already carried out by computers. Many base their
decisions on fairly simple algorithms designed to exploit tiny profit margins,
but others rely on more sophisticated long-term models.

Sorry, but this is a facile and ignorant mis-interpretation of what
financial models are doing.  Yes, people are running long-term financial
models as part of a trading strategy, but these models feed into very
short-term trading decisions.  If you looked at the output from these long-term
models, you would see that they are changing constantly as new data flows
in.  There is an old joke about two campers who see a bear growling at
them.  One of them starts putting his tennis shoes on.  The other one
says to him "Why are you putting your shoes on?  You can't outrun that
bear."   His friend replied "I don't have to outrun the bear.  I
just have to outrun you."  Traders' long-term models work the same.
They don't actually expect them to be right, they just want them to be better,
based on current conditions, than other traders' models, then they can make
money.

"¢ They
predicted global cooling in the 1970s

Indeed they did"¦. However, Schneider soon
realised he had overestimated the cooling effect of aerosol pollution and
underestimated the effect of CO₂, meaning warming was more likely
than cooling in the long run"¦.

The calls for action to prevent further
human-induced global warming, by contrast, are based on an enormous body of
research by thousands of scientists over more than a century that has been
subjected to intense "“ and sometimes ferocious "“ scrutiny. According to the
latest IPCC report, it is more than
90% certain that the world is already warming as a result of human activity

We have already dealt with aerosols, and unlike many skeptics I have not
really held the 1970's global cooling panic against the climate
community.  The last paragraph is just circular.  Saying the IPCC is
90% sure does not answer the arguments about what skeptics feel the IPCC is
ignoring.

"¢ It's
been far warmer in the past, what's the big deal?

First of all, it is worth bearing in mind that
any data on global temperatures before about 150 years ago is an estimate, a
reconstruction based on second-hand evidence such as ice cores and isotopic
ratios. The evidence becomes sparser the further back we look, and its
interpretation often involves a set of assumptions. In other words, a fair
amount of guesswork.

This is hilarious.  What happened to their confidence in Mann and
1000-year temperature reconstructions just a few myths back?  But to
continue, the answer is basically yes, but:

The important question is what
is causing the current, rapid warming? We cannot dismiss it as natural
variation just because the planet has been warmer at various times in the past.
Many studies suggest it can only be explained by taking into account human
activity.

Nor does the fact that it has
been warmer in the past mean that future warming is nothing to worry about. The
sea level has been tens of metres higher during past warm periods, enough to
submerge most major cities around the world.

Here is why it matters "“ beyond the laboratory evidence of the greenhouse
effect, which tells us merely that there is an affect and not how strong it is,
the main evidence cited by AGW supporters for current warming being man-made is
to try to show that current warming is somehow unprecedented, and therefore
unlikely to be natural.  So it is odd here that AGW supporters simply
shrug their shoulders here and say that it is not important that current
warming be unprecedented.

"¢ It's
too cold where I live - warming will be great

This does not sound too bad, and for many people
it won't be. Wealthy individuals and countries will be able to adapt to most
short-term changes, whether it means buying an air conditioner or switching to
crops better suited to the changing climate. Rainfall will fall in
mid-latitudes but rise in high latitudes, and initially agricultural yields
will probably.  Some regions will suffer, though. Africa could be hardest
hit, with yields predicted to halve in some countries as early as 2020.

As global temperature climbs to 3°C above
present levels - which is likely
to happen before the end of this century if greenhouse emissions continue
unabated - the consequences will become increasingly severe. More than a third
of species face extinction. Agricultural yields will start to fall in many
parts of the world. Millions of people will be at risk from coastal flooding.
Heatwaves, droughts, floods and wildfires will take an ever greater toll.

I hope readers will accept that I am not exaggerating or constructing straw
men when I talk about the dire predictions by AGW supporters.  There is
nothing here that we have not dealt with earlier, except perhaps the
rainfall.  Of late, AGW supporters seem to have shifted to rainfall
(rather than sea level rise) as their lead scary topic.  Note, however,
that even the IPCC admits that it and all of its modelers really do not
understand (even a little bit) the effect of global warming on rainfall and
drought.  Logic says that with more water evaporated, while global warming
may cause now local draughts, overall rainfall should increase.  I would
bet any amount of money that lower economic growth due to aggressive CO2 abatement
will have a far more deleterious effect on worldwide agricultural yields than
global warming.

"¢ Global
warming is down to the Sun, not humans

So what role, if any, have solar fluctuations
had in recent temperature changes? While we can work out how Earth's orbit has
changed going back many millions of years, we have no first-hand record of the
changes in solar output associated with sunspots before the 20^th century.

It is true that sunspot records go back to the
17^th century, but sunspots actually block the Sun's radiation. It is
the smaller bright spots (faculae) that increase the Sun's output and these
were not recorded until more recently. The correlation between sunspots and
bright faculae is not perfect, so estimates of solar activity based on sunspot
records may be out by as much as 30%.

The other method of working out past solar
activity is to measure levels of carbon-14 and beryllium-10 in tree rings and
ice cores. These isotopes are formed when cosmic rays hit the atmosphere, and
higher sunspot activity is associated with increases in the solar wind that
deflect more galactic cosmic rays away from Earth. Yet again, though, the
correlation is not perfect. What is more, recent evidence suggests that the
deposition of beryllium-10 can
be affected by climate changes, making it even less reliable as a measure
of past solar activity.

This is again a pretty hilarious statement.  One could easily argue
that temperature and CO2 proxies have at least as much
uncertainty.  One wonders why AGW advocates do not seem as concerned about
the errors in the proxies they hold dear.  But anyway, to continue:

But even if solar forcing in the past was more
important than this estimate suggests, as some scientists think, there is no
correlation between solar activity and the strong warming during the past 40
years. Claims that this is the case have not stood up to scrutiny (pdf document).

Direct measurements of solar output since 1978
show a steady rise and fall over the 11-year sunspot cycle, but no upwards or downward trend .

Similarly, there is no trend in direct
measurements of the Sun's ultraviolet output and in cosmic rays. So for the
period for which we have direct, reliable records, the Earth has warmed
dramatically even though there has been no corresponding rise in any kind of
solar activity.

This is another you-study-my-study pissing match.  I am happy to admit
that our knowledge of the sun's changing impact on climate is poor, and that it
is hard to separate out this one effect in a chaotic system.  I refuse to
fall into the same scientific hubris as AGW supporters.  However, those
who think the sun has some contribution to warming are buttressed by the
knowledge that they are working with the main driver of climate, rather than a
secondary variable.

"¢ It's
all down to cosmic rays

There is no convincing evidence
that cosmic rays are a major factor determining cloud cover. The ionising of
air by cosmic rays will impart an electric charge to aerosols, which in theory
could encourage them to clump together to form particles large enough for cloud
droplets to form around, called "cloud condensation nuclei".

But cloud physicists say it has
yet to be shown that such clumping occurs. And even if it does, it seems
far-fetched to expect any great effect on the amount of clouds in the atmosphere.
Most of the atmosphere, even relatively clean marine air, has plenty of cloud
condensation nuclei already.

A series of attempts by
Svensmark to show an effect have come unstuck. Initially, Svensmark claimed
there was a correlation between cosmic ray intensity and satellite measurements
of total cloud cover since the 1980s "“ yet a correlation does not prove cause
and effect. It could equally well reflect changes in solar irradiance, which
inversely correlate with cosmic ray intensity.

I am starting to notice a trend here of making statements about competing
that could be applied equally well to AGW theory.  And what about all
those points they made above, reminding us over and over that CO2 greenhouse
theory works in the lab.  Now the lab is not good enough?

However, I would accept that the cosmic ray theory is pretty undeveloped and
not acceptably proven.  It has had a number of fits and starts.  Just
like CO2 greenhouse theory, the cosmic ray effect on climate can be reproduced
in the lab, but it is really hard to parse out its effects in the chaotic
climate.

"¢ CO₂
isn't the most important greenhouse gas

At some of these overlaps, the
atmosphere already absorbs 100% of radiation, meaning that adding more
greenhouse gases cannot increase absorption at these specific frequencies. For
other frequencies, only a small proportion is currently absorbed, so higher
levels of greenhouse gases do make a difference.

This means that when it comes to
the greenhouse effect, two plus two does not equal four.

Wow!  An AGW supporter actually said this in public.  This is to
our point that there is a diminishing return from incremental CO2 in the
atmosphere.  Of course, they say this in the context of trying to show why
water isn't as important as it might seem, but still, it's there

But the overall quantities of these other gases
are tiny. Even allowing for the relative strength of the effects, CO₂
is still responsible for two-thirds
of the additional warming caused by all the greenhouse gases emitted as a
result of human activity.

Water vapour will play a huge role in the
centuries to come, though. Climate models, backed by satellite
measurements, suggest that the amount of water vapour in the upper
troposphere (about 5 to 10 kilometres up) will double by the end of this
century as temperatures rise.

This will result in roughly twice as much
warming than if water vapour remained constant. Changes in clouds could lead to
even greater amplification of the warming or reduce it "“ there is great uncertainty
about this. What is certain is that, in the jargon of climate science, water
vapour is a feedback, but not a forcing.

Again, I am not getting into this, we covered it plenty in the paper.
When they say "CO2 is still responsible for two-thirds of the additional
warming" (and remember this is an output of their models, not any other
analysis)  what they really mean is that "our models that were programmed
to have CO2 drive the climate show that CO2 drives the climate."
Note that in a three paragraph answer about the effect of water vapor as
a climate feedback, only three words "“ "or reduce it" "“ acknowledge that it
might actually have a negative feedback effect, despite the fact that even the
IPCC includes cloud cover as a negative feedback.  They just don't want to
admit a negative feedback might even exist.

"¢ The
lower atmosphere is cooling, not warming

One study in Science
revealed errors in the way satellite data had been collected and interpreted.
For instance, the orbit of satellites gradually slows, which has to be taken
into account because it affects the time of day at which temperature recording
are taken. This problem was always recognised, but the corrections were given
the wrong sign (negative instead positive and vice versa).

A second study, also
in Science, looked at the weather balloon data. Measurements of the air
temperature during the day can be skewed if the instruments are heated by
sunlight. Over the years the makers of weather balloons had come up with better
methods of preventing or correcting for this effect, but because no one had
taken these improvements into account, the more accurate measurements appeared
to show daytime temperatures getting cooler.

The corrected temperature records show that
tropospheric temperatures are indeed rising at roughly the same rate as surface
temperatures. Or, as a 2006 report by the US Climate Change Science Program (pdf) puts
it: "For recent decades, all current atmospheric data sets now show
global-average warming that is similar to the surface warming." This one
appears settled.

There is still some ambiguity in the tropics,
where most measurements show the surface warming faster than the upper
troposphere, whereas the models predict faster warming of the atmosphere.
However, this is a minor discrepancy compared with cooling of the entire
troposphere and could just be due to the errors of margin inherent in both the
observations and the models.

First, observe absolutely ruthless efforts to apply corrections and
adjustments to any measurement that does not fit their theory, while blithely
accepting the surface temperature measurements that we showed can be really
unreliable.  Given the choice of focusing on managing satellite
temperatures up or surface temperature down, you can see which they
chose.   Second, note that this is another narrow one study
conclusion.  AGW supporters frequently cite single studies (conducted by
AGW supporters) that overturn skeptics arguments as having "settled" the
issue.  There are still many reasons to think that troposphere temperature
increases are less than surface increases.  Finally, even temperature
increases that were the same between the surface and the troposphere would be a
real problem for AGW theory.  The authors here act like this
surface-troposphere issue is a minor deal, but in fact if AGW theory is right,
the troposphere has to warm more, because that is where the extra heat
is being absorbed.  This is not at all settled. 

"¢ Antarctica
is getting cooler, not warmer, disproving global warming

It is clear that the Antarctic Peninsula, which juts
out from the mainland of Antarctica towards South America, has warmed
significantly. The continent's interior was thought to have warmed too, but in
2002 a new analysis of
records from 1966 to 2000 concluded that it has cooled overall"¦.

Climate models do not predict an evenly spread
warming of the whole planet: changes in wind patterns and ocean currents can
change the distribution of heat, leading to some parts warming much faster than
average, while others cool at first.

Agreed

"¢ The
oceans are cooling

Now the authors of the 2006 study have submitted a
correction (pdf format). It turns out that a fault in the software on some
of the floats led to some temperature measurements being associated with the
wrong depth.

Meanwhile, work by other teams suggests that the
past warmth of the oceans has been overestimated. The problem was due to
expendable sensors that are thrown overboard and take measurements as they
sink.

I never had heard the claim that the oceans were cooling, so it does not
surprise me that they are not.  However, it is again interesting the
amount of due diligence that AGW supporter put in to the correction of any
temperature measurement the might refute global warming, while blithely
accepting the atrocious condition and biases in ground-based temperature
measurement because, well, because these instruments are telling the story they
want to hear.

"¢ The
cooling after 1940 shows CO₂ does not cause warming

The mid-century cooling appears to have been
largely due to a high concentration of sulphate aerosols in the atmosphere,
emitted by industrial activities and volcanic
eruptions. Sulphate aerosols have a cooling effect on the climate because
they scatter light from the Sun, reflecting its
energy back out into space.

The rise in sulphate aerosols was largely due to
the increase in industrial activities at the end of the second world war. In
addition, the large eruption of Mount Agung in 1963 produced aerosols which cooled the
lower atmosphere by about 0.5°C, while solar activity levelled off after
increasing at the beginning of the century

I think I was pretty fair in discussing the aerosol cooling hypothesis in
this paper, though many would disagree with the above statement's certainty.

Climate models that take into account only
natural factors, such as solar activity and volcanic eruptions, do not
reproduce 20th century temperatures very well. If, however, the models include
human emissions, including greenhouse gases and aerosols, they accurately reproduce
the 1940 to 1970 dip in temperatures.

I hope readers who have made it this far can supply the refutation of this
point:  Wrong, wrong, wrong.  Climate models initially matched
history poorly.  Today they match well because they have been tweaked and
adjusted and forced to match.  They match because they are programmed to
match.  And, as we discussed, they match only because they make
ridiculously low assumptions for natural forcings, and assume all natural
forcings causing temperatures to rise in the first half of the century
magically reversed in 1950, though there is no good evidence for it. 

"¢ It
was warmer during the Medieval period, with vineyards in England

In the southern hemisphere, the picture is even
more mixed, with evidence of both warm and cool periods around this time. The
Medieval Warm Period may have been partly a regional phenomenon, with the
extremes reflecting a redistribution of heat around the planet rather than a
big overall rise in the average global temperature.

What is clear, both from the temperature
reconstructions and from independent evidence "“ such as the extent of the
recent melting of mountain glaciers "“ is that the planet has been warmer in the
past few decades than at any time during the medieval period. In fact, the
world may not have been so warm for 6000 or even 125,000 years (see Climate myths: It has been warmer in the past,
what's the big deal?).

What really matters, though, is not how warm it
is now, but how warm it is going to get in the future. Even the temperature
reconstructions that show the greatest variations in the past 1000 years suggest
up until the 1980s, average temperature changes remained within a narrow band
spanning 1ºC at most. Now we are climbing out of that band, and the latest IPCC report (pdf format) predicts a further rise of
0.5ºC by 2030 and a whopping 6.4ºC by 2100 in the worst case scenario.

We have covered this pretty well in this paper, so again I won't go back
into it, except to highlight a couple of things we can learn from this
statement.  First, note the hubris again "“ it is warmer today than in the
last 125,000 years.  I sure wish there was a way to bet on this "“ I would
have only a one in 125,000 chance of being wrong in betting against this
statement.  Second, note the use of the worst case scenarios.  For
2100, we don't get the best case or even the average case, we get the worst
case.  Can you name another branch of science where people do this?
Can you imagine, say, a group out to measure the speed of light.  They are
going to get some middle figure with an error band of some range.
Wouldn't you expect them to day that they found the speed of light to be
so-and-so, plus or minus an error of such-and-such size?  If they were
climate scientists, they would instead announce that they have found the speed
of light could be as large as Z, that being the highest possible figure in
their error band.

"¢ We
are simply recovering from the Little Ice Age

Yet while there is some evidence of cold
intervals in parts of the southern hemisphere during this time, they do not appear to
coincide with those in the northern hemisphere. Such findings suggest the Little
Ice Age may have been more of a regional phenomenon than a global one.

Solar radiation was probably lower at times
during this period, especially during a dip in solar activity called the
Maunder minimum around 1700, but models and temperature reconstructions suggest
this would have reduced average global temperatures by 0.4ºC at most.

The larger falls in temperature in Europe and
North American may have been due to changes in atmospheric circulation over the
North Atlantic, or in the Gulf Stream, or both, reducing heat transport from
the tropics (see Climate
change sceptics lose vital argument).

The warming after the so-called Little Ice Age
may reflect both an increase in solar activity and a redistribution of heat
around the planet. In particular, the increase in global temperature in the
first half of the 20^th century may have been largely due to an increase
in solar activity. The continued warming in recent decades, however, cannot be
explained by increases in solar radiation alone

Remember the graphs we showed earlier "“ the arctic proxies look like the
current warming is a straight linear increase from the 1700s to today.  In
fact, in the IPCC spaghetti graph showing all those historic reconstructions,
they all show a natural warming from the 18^th and 19^th
century through the 20^th.  Again, AGW supporters really need to
explain why they are so confident that this natural warming trend stopped in
1945 or so, exactly and coincidently at the exact same moment that man-made
forcings caused the world to continue to warm, coincidently at about the same
rate it was warming naturally earlier in the century.

"¢ Warming
will cause an ice age in Europe

Few scientists think there will
be a rapid shutdown of circulation. Most ocean models predict no more than a
slowdown, probably towards the end of the century. This could slow or even
reverse some of the warming due to human emissions of greenhouse gases, which
might even be welcome in an overheated Europe, but the continent is not likely
to get colder than it is at present.

A slowdown in circulation would
affect many parts of the world by disrupting global rainfall patterns. But
these effects will be insignificant compared with the much greater changes
global warming will cause

I already mentioned that this had been refuted pretty well

"¢ Ice
cores show CO₂ increases lag behind temperature rises, disproving
the link to global warming

It takes about 5000 years for an
ice age to end and, after the initial 800 year lag, temperature and CO₂
concentrations in the atmosphere rise together for a further 4200 years.

What seems to have happened at
the end of the recent ice ages is that some factor "“ most probably orbital
changes "“ caused a rise in temperature. This led to an increase in CO₂,
resulting in further warming that caused more CO₂ to be released and
so on: a positive feedback that amplified a small change in temperature. At
some point, the shrinking of the ice sheets further amplified the warming.

Models suggest that rising
greenhouse gases, including CO₂, explains about 40% of the warming
as the ice ages ended. The figure is uncertain because it depends on how the
extent of ice coverage changed over time, and there is no way to pin this down
precisely.

I was extremely happy to see that they at least tried to
address the issue I raised, ie is it really realistic to have a process
dominated by positive feedback, and if so, why doesn't it run away.  Their
answer:

Finally, if higher temperatures lead
to more CO₂ and more CO₂ leads to higher temperatures,
why doesn't this positive feedback lead to a runaway greenhouse effect? There
are various limiting factors that kick in, the most important being that
infrared radiation emitted by Earth increases exponentially with temperature,
so as long as some infrared can escape from the atmosphere, at some point heat
loss catches up with heat retention.

Which might make sense EXCEPT that they are claiming that
today's temperature and level of CO2 are higher than these historical levels,
so we are already higher than the level where they claim "heat loss catches up
with heat retention."  So either their answer is right, and there is a
strong compensating process which is not built into their models, or they are
wrong and they still need to explain what keeps a positive feedback dominated
process from running away.

"¢ Ice
cores show CO₂ rising as temperatures fell

There are some mismatches though. Besides lags
at the end of ice ages, cores taken from the ice overlying the famous
lake below Vostok in Antarctica seemed to show that about 120,000 years
ago, the temperature plummeted sharply while CO₂ levels remained high
for many thousands of years.

The question is whether this is real or just a
reflection of the problems with working out the age of the trapped air and with
deuterium as a temperature indicator. Many researchers are working on ways to
independently date the air and the ice, and to improve temperature
reconstructions based on relative deuterium content. One involves working out
what is called the deuterium excess by comparing the relative amounts of
deuterium and oxygen-18 in the ice.

The deuterium excess reflects the temperature at
the sea surface where the water that later fell as snow evaporated, rather than
the surface temperature where the snow fell. It helps to reveal whether
variations in the relative deuterium content of the ice are a result of water
coming from a different source region rather than changes in local temperature.

In 2001, researchers used the deuterium excess to correct for some of the
problems with the temperature record of the Vostok ice core. Their results produce
a much closer fit between temperature and CO₂ levels and reduces the
mismatch around 120,000 years ago to a few thousand years.

I did not really raise this issue, as even the most enthusiastic AGW
supporter does not tend to claim that CO2 drives all historic temperature
changes.  However, again, note the pattern "“ any historic data that does
not fit with AGW data typically is scrutinized and "corrected." 
Articles discussing flaws in methodology in gathering such data are quickly published.
Contrast this with the difficulty scientists have in questioning any data that
supports AGW theory.  As we saw earlier, the New Scientist still can't
bring itself to utter the words "the Mann hockey stick was flawed."
Neither could the IPCC, they just sort of dropped it, or buried it in the midst
of 12 others, without even saying why the analysis that was the centerpiece of
their last report was strangely missing.

"¢ Mars
and Pluto are warming too

The Sun's energy output has not increased since
direct measurements began in 1978. If increased solar output really was
responsible, we should be seeing warming on all the planets and their moons,
not just Mars and Pluto.

Our solar system has eight planets, three dwarf
planets and quite a few moons with at least a rudimentary atmosphere, and thus
a climate of sorts. Their climates will be affected by local factors such as
orbital variations, changes in reflectance (albedo) and even volcanic
eruptions, so it would not be surprising if several planets and moons turn out
to be warming at any one time.

I agree we have a lot to learn about this, and nothing at all is
settled.  However, we now have evidence from at least 5 other terrestrial bodies
that are warming at the same time the Earth is warming.  Why do AGW
supporters resist at least investigating further?

"¢ Many
leading scientists question climate change

Climate change sceptics sometimes claim that
many leading scientists question climate change. Well, it all depends on what
you mean by "many" and "leading". For instance, in April
2006, 60 "leading scientists" signed a letter urging Canada's
new prime minister to review his country's commitment to the Kyoto protocol.

This appears to be the biggest recent list of
sceptics. Yet many, if not most, of the 60 signatories are not actively engaged
in studying climate change: some are not scientists at all and at least 15 are
retired.

Compare that with the dozens of statements on
climate change from various scientific organisations around the world
representing tens of thousands of scientists, the consensus position
represented by the IPCC reports and the 11,000 signatories to a petition condemning the Bush administration's
stance on climate science.

I have carefully avoided the game of dueling scientific numbers.  As to
the claim that the skeptic list "are not actively engaged in studying
climate change: some are not scientists at all and at least 15 are retired" I
would be thrilled if AGW supporters held to this standard in making their own
numbers.  But, they manage to abandon this standard by the next paragraph,
when they claim the pro-AGW numbers, like the 11,000, are open to the same
criticism (since there are only 500-600 true climate scientists in the world,
vs. physicist, meteorologists, etc). 

"¢ It's
all a conspiracy

Now that there is a consensus, those whose
findings challenge the orthodoxy are always going have a tougher time
convincing their peers, as in any field of science. For this reason, there will
inevitably be pressure on scientists who challenge the consensus. But findings
or ideas that clash with the idea of human-induced global warming have not been
suppressed or ignored "“ far from it.

Journalists do have an interest in promoting
themselves (and their books), while their employers want to boost their
audience and sell advertising. Publicity helps with all these aims, but you get
far more publicity by challenging the mainstream view than by promoting it.
Which helps explain why so many sections of the media continue to publish or
broadcast the claims of deniers, regardless of their merit.

The notion of a "conspiracy" of course, is a useful straw man, implying
devious villains in the SPECTRE conference room planning the overthrow of the
world.   I won't argue the point again, except to encourage you to
watch the news with a critical eye, and decide for yourself.  However, just
to get you started, ask yourself if these events are signs of healthy, unbiased
science:

· A
group of AGW supporters are trying to get the British government to use force
to block the publication of a skeptical movie (the Global Warming Swindle)

· AGW
supporters in California have included skeptical scientists such as MIT's Dr.
Richard Lindzen as defendants in a law suit, asking that damages be paid by
people and companies whose public speech doesn't conform to AGW theory

· Many
AGW skeptics have been unable to get scientists who have published publicly
funded research to reveal their data and methodology for critique.
Freedom of Information Act (FOIA) requests have become a necessary tool of
climate skeptics.

· When
a group began photographing temperature measurement points to document the
shortcomings in historical surface temperature measurements, the NOAA pulled
the locations of its measurement stations off the Internet so that these US
citizens could no longer take pictures of and critique US government
installations.

· Scientists
who question AGW theory are equated by AGW supporters with Holocaust deniers.

"¢ Hurricane
Katrina was caused by global warming

More data is needed settle the issue. Some are
looking to natural records of past
hurricane activity in stalagmites, lake deposits and coral rubble. Others
are re-analysing existing databases. In February 2007, one such re-analysis
concluded that over the past two decades, hurricane intensity has increased
in the Atlantic but not in other parts of the world (pdf format).

Yet another complicating factor is that changes
in climate can also change the paths that tropical cyclones tend to take,
determining whether they remain over oceans or strike land.

What every one agrees on is that over the past
few decades there has been a huge rise in the number of people being killed or
injured by hurricanes, and in damage to infrastructure, and this trend looks
set to continue. The main reason for this, however, is that more and more
people are living and building in hurricane zones.

Most of these three paragraphs is entirely correct "“ there is no evidence
that hurricane numbers or intensity are effected by global warming, and if they
are, whether they are increased or decreased.  However, Hurricane Katrina
was most certainly NOT caused by global warming.  Why can't they just say
that?   It may have been made stronger or weaker.  Its course
may have been altered.   But it was not created by warming.  By
the way, the year after Katrina saw a much smaller than average Atlantic
hurricane season.

"¢ Higher
CO₂ levels will boost plant growth and food production

But it is extremely difficult to generalise
about the overall impact on plant growth. Numerous groups around the world have
been conducting experiments in which plots of land
are supplied with enhanced CO₂, while comparable nearby plots remain
at normal levels.

While these experiments typically have found
initial elevations in the rate of plant growth, these have tended to level off
within a few years. In most cases this has been found to be the result of some
other limiting factor, such as the availability of nitrogen or water.

So the answer is yes, but there is a diminishing return at some point.
Isn't that the same as can be said for the CO2 greenhouse effect?

Predicting the world's overall changes in food
production in response to elevated CO₂ is virtually impossible.
Global production is expected to rise until the increase in local average
temperatures exceeds 3°C, but then start to fall. In tropical and dry regions
increases of just 1 to 2°C are expected to lead to falls in production. In
marginal lands where water is the greatest constraint, which includes much of
the developing world but also regions such as the western US, the losses may
greatly exceed the gains.

Have you noticed yet that things that might hurt the AGW-interventionist's
case always seem "impossible to predict" while the climate is well within our
prediction capabilities?

As for food crops, the factors are more complex.
The crops most widely used in the world for food in many cases depend on
particular combinations of soil type, climate, moisture, weather patterns and
the infrastructure of equipment, experience and distribution systems. If the
climate warms so much that crops no longer thrive in their traditional settings,
farming of some crops may be able to shift to adjacent areas, but others may
not. Rich farmers and countries will be able to adapt more easily than poorer
ones.

I love the rich-poor language.  The leftish New Scientist simply can't
help itself.  But I will accept this statement, and go further:  This
is the reason that aggressive actions to reduce CO2 that reduce economic
growth, particularly in the developing world, may not make sense.  To the
extent that some climate change will occur no matter what, or is already
programmed by our past actions, then a richer world can deal with it better
than a poorer one.

"¢ Polar
bear numbers are increasing

Yet recently there have been
claims that polar bear populations are increasing. So what's going on? There
are thought to be between 20,000 and 25,000 polar bears in 19 population groups
around the Arctic. While polar bear numbers are increasing in two of these
populations, two others are definitely in decline. We don't really know how the
rest of the populations are faring, so the truth is that no one can say for
sure how overall numbers are changing.

Again, I love this.  We can know the global temperature
increase over a century to a tenth of a degree but it is impossible to count
polar bears.

A comprehensive review (pdf) by the US Fish and Wildlife Service
concluded that shrinking sea ice is the primary cause for the decline seen in
these populations, and it recently proposed listing
polar bears as threatened (pdf) under the Endangered Species Act. The
International Conservation Union projects the bears' numbers will drop by 30% by 2050
(pdf) due to continued loss of Arctic sea ice.

Note that down 30% (which coming from an environmental
advocacy ground has got to be considered the most extreme possible estimate) is
not "extinct."  The article fails to address at all the issue that polar
bears have survived through eras when Arctic sea ice melted completely in the
summers.  And there are many reasons for threats to polar bear numbers "“
most experts would say that hunting and threats to habitat are much more
important factors than global temperatures.

The table of contents for the rest of this paper, . 4A Layman's Guide to Anthropogenic Global Warming (AGW) is here.  Free pdf of this Climate Skepticism paper is here and print version is sold at cost here

The open comment thread for this paper can be found here. 

James Christopher via Kurt Loder via Cattalarchy:

After marveling at Moore's rosy view of the British health care system
in "Sicko," Christopher wrote, "What he hasn't done is lie in a
corridor all night at the Royal Free [Hospital] watching his severed
toe disintegrate in a plastic cup of melted ice.  I have."

The whole review is worth reading.  Many folks seem to think Michael Moore is brilliant until he makes a film about something with which they are actually familiar.  Which, come to think of it, encapsulates my entire view of the media, not just Michael Moore, as well.  Nothing will reduce your confidence in the media more than reading an article on a topic about which you have intimate knowledge.

In the past, I have argued that it is odd that climate scientists ignore the changes in solar activity in their models.  Despite the fact the sun's activity is at a very high level (vs. the past several hundred years) the most recent IPCC report says they think that earth's temperatures would have fallen in the 20th century absent anthropogenic effects.  So then why is this happening:

Mars is being hit by rapid climate change and it is happening so fast that the red planet could lose its southern ice cap,
writes Jonathan Leake.

Scientists from Nasa say that Mars has warmed by about 0.5C
since the 1970s. This is similar to the warming experienced on Earth
over approximately the same period.

Since there is no known life on Mars it suggests rapid changes in planetary climates could be natural phenomena.

The
mechanism at work on Mars appears, however, to be different from that
on Earth. One of the researchers, Lori Fenton, believes variations in
radiation and temperature across the surface of the Red Planet are
generating strong winds.

In
a paper published in the journal Nature, she suggests that such winds
can stir up giant dust storms, trapping heat and raising the planet's
temperature.

Almost every planet in the Solar System has been found to be warming over the last several decades.  At what point do we turn our attention, at least in part, to Mr. Sun?  (Hat tip Q&O Blog)

Until I watched the Global Warming Swindle, I had confined my criticisms of anthropogenic global warming theory to two general areas:  1)  The models for future warming are overstated and 2) The costs of warming may not justify the costs of preventing it.

The movie offered an alternate hypothesis about global warming and climate change that, rather than refute the magnitude of anthropogenic global warming, provided a counter hypothesis.  You should watch the movie, but the counter hypothesis is that historic temperature changes have been the result of variations in solar activity.  Rather than causing these changes, increased atmospheric CO2 levels resulted from these temperature increases, as rising ocean temperatures caused CO2 to be driven out of solution from the world's oceans.

I thought one of the more compelling charts from Al Gore's pPwerpoint deck, which made the movie An Invconvienent Truth, was the hundred thousand year close relationship between atmospheric CO2 levels and global temperature, as discovered in ice core analysis.  The Swindle movie, however, claims that Gore is hiding something from that analysis in the scale of his chart -- that the same ice core analyses show that global temperature changes have led CO2 concentration changes by as much as 800 years.  (short 2-minute snippet of this part of the movie here, highly recommended).

Well, this would certainly be something important to sort out.  I have not done much real science since my physics days at Princeton, but my sense is that, except maybe at the quantum level, when B follows A it is hard to argue that B caused A.

So I have poked around a bit to see -- is this really what the ice core data shows, or is Swindle just making up facts or taking facts out of context ala the truther hypotheses about 9/11?  Well, it turns out that everyone, even the die-hard global warming supporters, accept this 800-year lag as correct (Watch the Al Gore clip above -- it is clear he knows. You can tell by the very careful way he describes the relationship).  LuboÃ…¡ Motl summarizes in his blog:

However, the most popular - and the most straightforward - explanation
of the direction of the causal relationship is the fact that in all
cases, the CO2 concentration only changed its trend roughly 800 years
after temperature had done the same thing. There have been many papers
that showed this fact and incidentally, no one seems to disagree with
it....

The whole "group" at RealClimate.ORG
[ed: one of the leading sites promoting the anthropogenic theory] has agreed that there was a lag. But they say that in the first 800
years when the influence of temperature on CO2 is manifest, it was
indeed temperature that drove the gases. But in the remaining 4200
years of the trend, it was surely the other way around: CO2 escalated
the warming, they say.

Frequent readers will know that I have criticized forward looking climate models on many occasions for being too reliant on positive feedback processes.  For example, in the most recent IPCC models, over 2/3 of future warming come not from CO2 but from various positive feedback effects (section 8.6 of the 2007 report). 

The folks at RealClimate.org are similarly positing a positive feedback mechanism in the past -- "something" causes initial warming, which drives CO2 to outgas from the oceans, which causes more warming, etc. 

I am not sure I have ever done so, so let me take a minute to discuss positive feedbacks.  This is something I know a fair amount about, since my specialization at school in mechanical engineering was in control theory and feedback processes.  Negative feedback means that when you disturb an object or system in some way, forces tend to counteract this disturbance.  Positive feedback means that the forces at work tend to reinforce or magnify a disturbance.

You can think of negative feedback as a ball sitting in the bottom of a bowl.  Flick the ball in any direction, and the sides of the bowl, gravity, and friction will tend to bring the ball back to rest in the center of the bowl.  Positive feedback is a ball balanced on the pointy tip of a mountain.  Flick the ball, and it will start rolling faster and faster down the mountain, and end up a long way away from where it started with only a small initial flick.

Almost every process you can think of in nature operates by negative feedback.  Roll a ball, and eventually friction and wind resistance bring it to a stop (except, apparently, on the greens at Augusta).  There is a good reason for this.  Positive feedback breeds instability, and processes that operate by positive feedback are dangerous, and usually end up in extreme states.  These processes tend to "run away."   I can illustrate this with an example:  Nuclear fission is a positive feedback process.  A high energy neutron causes the fission reaction, which produces multiple high energy neutrons that can cause more fission.  It is a runaway process, it is dangerous and unstable.  We should be happy there are not more positive feedback processes on our planet.

Since negative feedback processes are much more common, and since positive feedback processes almost never yield a stable system, scientists assume that processes they meet are negative feedback until proven otherwise.  Except in climate, it seems, where everyone assumes positive feedback is common.

Back to the climate question.  The anthropogenic guys are saying that when the earth heated, it caused CO2 to outgas from the oceans, which in turn caused more warming, which causes more outgassing, etc.  But where does it stop?  If this is really how things work, why isn't the Earth more like Venus?  If you are going to posit such a runaway process, you have to also posit what stops it.  So far, the only thing I can think of is that the process would stop when the all bands of light that are absorbable by CO2 are fully saturated.

But the feedback is worse than this.  I won't go into it now, but as you can see from this post, or from section 8.6 of the 2007 IPCC report, the current climate models assume that warming from CO2 itself yields further positive feedback effects (e.g. more humidity) that further accelerate warming, acting as a multiplier as great as 3-times on CO2 effects alone.

So here is the RealClimate view of the world:  Any small warming from some outside source (think Mr. Sun) is accelerated by outgassing CO2 which is in turn accelerated by these other effects in their climate models.  In other words, global temperature is a ball sitting perched on the top of a mountain, and the smallest nudge causes it to accelerate away.  This is the point at which, despite having only limited knowledge about the climate, I have to call bullshit!  There is just no way our planet's climate could be as stable as it has been long-term and be built on such positive feedback loops.  No way.  Either these folks are over-estimating the positive feedback or ignoring negative feedbacks or both.  (and yes, I know we have had ice ages and such but against the backdrop of the range of temperatures the Earth theoretically could have in different situations, our climate variation has been small).

Postscript:  The other day I mentioned that it was funny a group studying solar output felt the need to put in a statement validating anthropogenic global warming despite the fact that nothing in their research said any such thing.  Motl points to a similar thing in the ice core studies:

Well, the website tells us that the paper that reported the lag contained the following sentence:

• ...
  is still in full agreement with the idea that CO2 plays, through its
  greenhouse effect, a key role in amplifying the initial orbital forcing
  ...

Again, this statement was included despite the fact that their study pretty clearly refutes some key premises in anthropogenic global warming theory.  It's become a phrase like "no animal was hurt in the filming of this movie" that you have to append to every climate study.  Or, probably a better analogy, it is like Copernicus spending a few chapters assuring everyone he still believes in God and the Bible before he lays out his heliocentric view of the solar system. 

Update: All this is not to say that there are not positive feedback loops in climate.  Ice albedo is probably one -- as temperatures rise, ice melts and less sunlight is reflected back into space by the ice so the world warms more.  My point is that it does not make any sense to say that positive feedback processes dominate.

Correction: Like a moron, I have been using anthropomorphic rather than anthropogenic to refer to man-made climate effects.  Oops.  Thanks to my reader who corrected me.  I have fixed this article but am too lazy to go back and edit the past.

Further Update:  The irony of my correction above juxtaposed against the title of the previous post is not lost on me.

Update to the Postscript: Oh my god, here it is again.  An NOAA-funded study comes to the conclusion that global warming might actually reduce hurricane strength and frequency.  Nowhere in the study did the researchers touch any topic related to anthropogenic warming -- they just studied what might happen to hurricanes if the world warms for any reason.  But here is that disclaimer again:

"This study does not, in any way, undermine the widespread consensus in the scientific community about the reality of global warming," said co-author Brian Soden, Rosenstiel School associate professor of meteorology and physical oceanography whose research is partly funded by NOAA.

Does the NOAA and other funding bodies actually require that this boilerplate be added to every study?

I found this conjured up a terribly funny image in my mind.  JunkScience has a challenge to climate journalists to try the math to test for themselves whether current global warming estimates make any sense.  The challenge per se is not funny, but the picture of a journalist... well, read the challenge first:

We believe climate
models are programmed with excessive climate sensitivity based on a
flawed understanding of past ice ages. Moreover, climate models wrongly
magnify potential warming to accommodate positive feedback mechanisms
while comparison with empirical measure shows negative feedback dominates, reducing warming experienced to about half theoretical values.

The challenge is for you to actually check the numbers -- see for yourselves whether we are wrong or not. Look up Stefan's Constant or just use 5.67 x 10^-8
(close enough for our purpose but look it up to be sure). The textbook
derivation of globally averaged greenhouse, using Stefan's Constant,
evaluates to roughly 33 °C and 150 Wm^-2. The IPCC Third Assessment Report alt: Third Assessment Report (Equation 6.1) states: "The climate sensitivity parameter (global mean surface temperature response ΔT_s to the radiative forcing ΔF) is defined as: ΔT_s / ΔF = λ." A blackbody-equivalent Earth climate sensitivity parameter (λ) would be 33 / 150 = 0.22 °C per Wm^-2. Real world measures (here) indicate Earth responds with only half the efficiency of a blackbody with a lambda (λ) value of just 0.1 °C per Wm^-2.

Now use it to check the assertion: "Global climate forcing was about 6 1/2 W/m²
less than in the current interglacial period. This forcing maintains a
global temperature difference of 5 °C, implying a climate sensitivity
of 3/4 ± 1/4 °C per W/m²." Either consult your texts for Earth's temperature in Kelvin and any other numbers you need or see the numbers we've used here. Off you go -- we'll wait. If you can show us where we're wrong we'll retract and correct.

Can anyone out there picture your favorite journalist trying to do this?  Many journalists followed the tried-and-true career path of:  Avoid math altogether --> Become an English major --> Become a journalist as an alternative to playing the guitar in subway stations.  Who else would love to see Maureen Dowd taking on this analysis?

I finally saw Casino Royale this weekend, and though it has been said in many other reviews, I will repeat it:  This is the best Bond ever.  More than just changing Bond actors, the movie represents a retooling of a Bond franchise gone way, way astray in the Roger Moore years.  Pierce Brosnan did a good job bringing Bond back to reality, but he was still too pretty-boy to really portray the ice-cold, very serious Bond of the books.  The double-0's are supposed to be hired as assassins (license to kill, remember) and not because they look good in a tux.  Bond in the book Casino Royale, for example, doesn't even want Vesper Lynd around because he refuses to be distracted by women on duty.  The Bond of recent movies seems to do nothing but get distracted by women on duty.

Casino Royale was always my favorite of the Bond books, and I am pleased that it was this book that brought the franchise into a new era.  Yes, Q and the gadgets are gone, and even some of the classic lines are mostly absent (though shaken not stirred draws a funny joke).  In their place is much sharper and more interesting dialog.  Judie Dench finally gets a role as M that does justice to some of her acting talents.  And  Daniel Craig is fabulous.   

This is also by far the closest any Bond movie has stuck to it's namesake book.  The book was a bit light on action, so rather than try to work it in where it does not belong, they grafted the action onto the front of the movie, which is essentially a prequel to the action in the book.  The book begins about where Bond gets approval to go after LeChiffre in a card game, and from that point forward it follows the book almost exactly, with some minor updating.  The only small amount of pain was seeing Bond playing Texas hold'em rather than Baccarat, but after seeing the movie, poker works much better than Baccarat did in the book - the element of bluffing adds to the tension.

Don't worry, the action is still there.  The opening chase scene is fabulous, all the more so because it is mostly free of gadgets and aircraft and missiles and... you get the idea.  Instead, you get Bond at his most ruthless as well as the improvisational Bond we haven't seen since Sean Connery.  First movie in a while I immediately wanted to see again.  And first action movie in forever where the plot made any sense and the writing was sharp.

Update:  Please enjoy this post; however, I have published a (free) more comprehensive guide to the skeptics arguments concerning man-made global warming.  You can find the HTML version here and a free pdf download here.

A few days ago, my wife announced to me that she wanted me to take her to
"An Inconvenient Truth", the recent movie vehicle for communicating
Al Gore's views on climate change.  I told my wife that I found the
climate issue incredibly interesting -- I have always had a passion for
inter-disciplinary science and climate requires integration of bits not just
from climate science but from economics, statistics, biology, and more.  I
told her I would love to see a true documentary on climate change, but I was as
interested in seeing a "science" film from the group that put this movie
together as I presume she was in seeing a "even-handed" movie on
abortion produced by the Catholic Church.

Never-the-less, she has insisted, so I put together a skeptic's primer for
her, which I will also share with you.  Note that I am not actively involved in climate research myself, so the following is my admittedly incomplete understanding of all the issues.  It is meant to raise issues that you may not find discussed in most global warming accounts.

Overview:  The earth has warmed by 2/3 of a degree to as much as a degree (all temperatures in Celsius)
over the last 100 years, of which man may be responsible for no more than half
through CO2 emissions.  The poles, which are important to all the global
deluge scare scenarios, have warmed less than the average.  Man's CO2
emissions will warm the earth another degree or so over the next 100
years.  There is a possibility the warming will be greater than this, but
scary-large warming numbers that are typical of most climate reports today
depend on positive feedback loops in the climate that are theoretical and whose
effect has not yet been observed.  The effects of warming will be a mix of
positive and negative outcomes, recognizing that the former never seem to get
discussed in various media scare stories.  If the effects of warming are a
net negative on mankind, it is not clear that this negative outweighs the costs
in terms of lost economic growth (and the poverty, disease, and misery that
comes with lower growth) of avoiding the warming.  In other words, I
suspect a warmer but richer world may be better than a cooler but poorer world.

The Hockey Stick:  The Hockey Stick graph as become the emblem,
the sort of coat-of-arms, for the climate change intelligentsia.  Until
recently, the climate consensus for the last 1000 years, taken from reams of
historical records (things like the history of X river freezing in winter or Y
region having droughts) was this:

This chart is from the 1990 IPCC climate report, and in it you can see
features that both historians and scientists have discussed for years -- the
warm period during the Middle Ages and the "little ice age" of the
late 17th century.  Of course, this chart is barely better than a guess,
as are most all historical climate surveys.  For example, 3/4 of the earth
is water (where few consistent observations were taken) and only a small percentage of the rest was "civilized" to
the extent of having any historical records.  In addition to historical
records, scientists try to use things like ice cores and tree rings to get a
sense of long-term global climate patterns.

This long-held consensus changed with Mann, et. al., a study that created a new climate
picture for the last millennia that has immediately caught the fancy of nearly
every advocate of climate Armageddon.

For obvious reasons, this graph is called "the hockey stick" and
it is beloved by the global warming crowd because it hammers home the following
message:  Climate has been incredibly steady over the past 900 years with a flat to declining temperature trend until
man came along and caused a dramatic shift.  Based on this analysis, Mann
famously declared that the 1990's were the warmest decade in a millennia and
that 1998 was the hottest year in the last 1000 years.  (For real hubris, check
out this recent USAToday
graphic, which purports to know the world's temperature within .001 degree
for every year going back two thousand years)

In fact, what Mann's chart shows for the last 100 years is about what I said in my overview - that
the world has warmed a degree and that man maybe has contributed up to half of
this.  Notice that tacked onto the end of the previous consensus view, the
last 100 years seem like it might just be the start of another natural cyclical
climate variation.    Not necesarily a reason for panic.  Ah,
but Mann's chart!  That's a chart that anyone eager to have the government
intervene massively in the economy is bound to love. It says that we are currently entering an unprecedented anomoly, and that the chief suspect for creating this change must be human civilization.

So is Mann right?  Well, a couple of things to note.  First, its
instructive to observe how eagerly the climate community threw out its old
consensus based on years of research in favor of Mann's study.  It's
unusual for a healthy
scientific community to throw out their old consensus on the basis of one
study, especially when no one had replicated its findings independently.
Which no one has ever been able to do, since Mann has refused to share his
models or methodology details.  In fact, it took a US Congressional subpoena
to get any of his underlying models into the public domain.  This behavior
by a scientist would normally engender ENORMOUS skepticism in the community --
normally, I mean, except for in climate science, where mountaintop revelation without 3rd party repeatability
is OK as long as it supports a dire man-made climate catastrophe model.
In short, climate change advocates wanted the study to be true, because it was such a
powerful image to show the public.

Despite Mann's reticence to allow anyone to check his work, skeptics still
began to emerge.    Take that big temperature bulge in the Middle
Ages shown in the previous concensus view.  This bulge was annoying to climate
interventionists, because it showed that large variations in temperature on a
global scale can be natural and not necessarily the fault of modern man.
But Mann made this whole medieval bulge go away.  How?  Well, one of
the early revelations about Mann's work is that all the data before 1450 or so
comes from studying the tree rings of one single tree.  Yes, that's one tree
(1).  Using the evidence of this one tree, Mann flattened the temperature
over the 500 year period from 1000-1500 and made the Medieval warm period just go poof.  Wow!

The bigger criticism of Mann has come from statisticians.  Two Canadian
statisticians began questioning Mann's methodology, arguing that his
statistical approach was incorrect.  They demonstrated that Mann's
statistical approach was biased towards creating hockey sticks, and they showed
how the Mann model could be applied to random noise and produce a hockey
stick.   The climate change establishment did not take this criticism
well, and tried their hardest to rip these two guys up.  In fact, you might have believed that the two had been molesting little boys or declaring the world is flat rather than just questioning another scientist's statistical methodology. 

Recently, a US Congressional Committee asked a group of independent statisticians led by
Dr. Edward Wegman, Chair of the National Science Foundation's Statistical
Sciences Committee, to evaluate the Mann methodology.  Wegman
et. al. savaged the Mann methodology as well as the peer review process
within the climate community:

It is important to note the isolation of the paleoclimate community; even
though they rely heavily on statistical methods they do not seem to be
interacting with the statistical community. Additionally, we judge that the
sharing of research materials, data and results was haphazardly and grudgingly
done. In this case we judge that there was too much reliance on peer review,
which was not necessarily independent. Moreover, the work has been sufficiently
politicized that this community can hardly reassess their public positions
without losing credibility. Overall, our committee believes that Dr. Mann's
assessments that the decade of the 1990s was the hottest decade of the
millennium and that 1998 was the hottest year of the millennium cannot be
supported by his analysis.

Further, Wegman concurred on almost every point with the Canadians, coming to the conclusion that the hockey stick was deepfly flawed.  In most other scientific communities, the Mann analysis would have been sent
to the dustbin along with cold fusion and Archbishop James Ussher's dating of
the earth to October 23, 4004 BC.
The problem is that the Mann chart has become too politically important.  Prominent men
like Al Gore have waved it around for years and put it in his books.  No
one in the core of the climate community can back away from the hockey stick
now without the rest of the world asking, rightly, what else is wrong with your
analyses?  If I seem too hard on the climate science community, then
consider this
quote from National Center for Atmospheric Research (NOAA) climate researcher and global warming action promoter,
Steven Schneider:

We have to offer up scary scenarios, make simplified, dramatic statements,
and make little mention of any doubts we have. Each of us has to decide what
the right balance is between being effective and being honest.

Now you know why, for all its flaws, you will continue to see the hockey
stick in the press.  Because it is not about the facts, but about "scary scenarios" and "dramatic statements".

Has Man Been Causing the Warming?

Yes, some of it.  But its a little more complicated than the global
warming community lets on.   First, note the last 100 years of the
hockey stick.  The big upwards spike begins in 1900, long before any large
man-made concentrations of CO2 were put into the atmosphere.  In fact,
even those most fanatical about assigning maximum blame for climate change to
man don't blame man-made effects for most of the first half of the 20th century
temperature spike. 

Which begs the question, what caused the 1900-1940 spike of about 1/2 a
degree?  Answer:  Nobody really knows.  Which begs the follow-on
question:  If we don't know what caused the 1900-1940 run-up, how do we
know that this same force is not responsible for some of the run-up since
1950?  Answer:  We don't.  As I will explain below, climate
scientists trying to validate their models have reasons for wanting the
post-1950 temperature rise to be all man-made.  But just because they
assume it to be due to man-made rises in atmospheric CO2 concentrations does
not make it so -- correlation does not equal causation.

Well, what else could be causing this increase?  It could at least partially be
natural cyclical variations in climate that we don't really understand.
Or it could be something more obvious, like, say, the sun was brighter.  I
can imagine your reaction -- no way it could be just a brighter sun,
Coyote.  I mean, that's the first thing the climate scientists would check
if earth temperatures were rising, right?

This chart compiled from data by Judith Lean of the Naval Research Library
and charted from her data at NOAA by Junkscience.com
shows that interestingly, the sun's output does appear to be higher today than they have been in many, perhaps hundreds of years.  Would such increased activity be
expected to result in higher earth temperatures?  I don't know, but if you
think it odd that scientists talk about global warming without mentioning how
hot the sun is, well, welcome to the world of climate science.   Its kind of like scrambling to find out why your room is too hot without first checking to see where the thermostat on the furnace is set.  More
on the sun's variance
and climate change here.

Future Warming:  The key question, of course, is about future warming - i.e.,
based on man's economic growth and projected output of CO2, how much can the
world be expected to warm, say over the next 50-100 years.  I don't know
what the movie "An Inconvenient Truth" will claim until I see it, but
most recent studies have shown warming from 2-8 degrees (consistent with what is depicted by the
USAToday graphic linked above).

There are lots of issues with these forecasts that occasionally might even get
mentioned in the popular press.  Some issues are unavoidable, like the
inherent complexity and unpredictability of climate.  Some issues probably
could be avoided, like the egregiously bad economic forecasting that drives CO2
output forecasts in many of these models.  I won't delve into these issues
much, except to say that we are dealing with massively complex systems.
If an economist came up with a computer model that he claimed could predict the
market value of every house in the world in the year 2106 within $10,000, would
you believe him?  No, you would say he was nuts -- there is way to
much uncertainty.  Climate, of course, is not the same as housing
prices.  It is in fact, much, much more complex and more difficult to
predict. 

All these forecasts are created by a pretty insular and incestuous climate
science community that seems to compete to see who can come up with the most
dire forecast.  Certainly there are financial incentives to be as aggressive
as possible in forecasting climate change, since funding dollars tend to get
channeled to the most pessimistic.   The global warming community spends
a lot of time with ad hominem attacks on skeptics, usually accusing them of
being in the pay of oil and power companies, but they all know that their own
funding in turn would dry up rapidly if they were to show any bit of skepticism
in their own work.

Leaving aside all the other modeling problems and focus on one fact:
Most climate scientists would agree that if you focus narrowly just on the
effects of CO2 on warming, that even under the most extravagant assumptions of
CO2 production, the world will not warm more than a degree or two in total,
some of which we have already seen.  The reason is that the effect of CO2
concentration on global temperature is logarithmic.  This means that
increasing concentrations of CO2 have diminishing returns on temperature.
For example, if the first doubling of CO2 concentration raises temperatures by
a degree, then the next doubling may only raise it by a tenths of a
degree.  This is because CO2 only absorbs sunlight and energy in certain
frequency bands and this ability to absorb energy gets saturated, much like a
pot of water can only dissolve so much salt before it is saturated.

There is fair amount of argument over just how saturated the CO2 layers are
in terms of energy absorption, but most scientists will agree that at some
point, in isolation, additional CO2 added to the atmosphere by man stops having
any significant effect on global temperature.

So how do we get these dire forecasts of 6, 7, 8 degrees of warming?
Well, I was careful to say the effect of CO2 in isolation maxes
out.  To get to higher levels of warming, scientists posit "positive
feedback loops" that augment the warming effect.  Positive feedback generally means that once a process gets going in a direction, there is some force that will accelerate the process
faster or farther in the same direction.  Negative feedback means that
once a process is moving there is some force that tends to try to slow the process back down.
Positive feedback is a boulder balanced on the top of a mountain, where one
push will cause it to roll down the mountain faster and faster; Negative
feedback is a boulder in a valley, where despite lots of effort, the rock will
keep coming to rest back where it started.

In global warming models, water vapor plays a key role as both a positive and a negative feedback loop to climate change.  Water vapor
is a far more powerful greenhouse gas than CO2.  It comes into play because CO2 driven warming will
put more water vapor in the atmosphere, because greater heat will vaporize more
water.  If this extra vapor shows up as more humid clear air, then this in
turn will cause more warming as the extra water vapor absorbs more energy and
accelerates warming.  However, if this extra water vapor shows up as
clouds, the cloud cover will tend to reflect energy back into space and retard
temperature growth. 

Which will happen?  Well, nobody knows.  And this is just one
example of the many, many feedback loops that scientists are able to posit but
not prove. And climate scientists are coming up
with numerous other positive feedback looks.  As one skeptic put it:

Regardless, climate models are made
interesting by the inclusion of "positive feedbacks" (multiplier
effects) so that a small temperature increment expected from increasing
atmospheric carbon dioxide invokes large increases in water vapor, which seem
to produce exponential rather than logarithmic temperature response in the
models. It appears to have become something of a game to see who can add in the
most creative feedback mechanisms to produce the scariest warming scenarios
from their models but there remains no evidence the planet includes any such
effects or behaves in a similar manner.

So, is it reasonable to assume these feedback loops?  First, none have
really been proven empirically, which does not of course necessarily make them
wrong.  More damning is the fact that models using mostly positive feedback
loops do a terrible job of modeling the last 100 years.  It is a perfectly
reasonable back check on any model to see if it predicts history.   Most of the aggressive climate models (ie the ones that tend to get quoted in the press) turn out to predict a warming for the
last 50 years far above what we have actually observed, which of course might make one
suspicious of their ability to predict the future.  A while back, I said
that climate scientists had a strong incentive to "claim" as much of
the 20th century warming as possible and attribute it to man.  This is
why:  The need to validate models that predict a lot of manmade warming
over the last 50 years that hasn't shown up.  Scientists will tell you
that they have fixed these problems, but we skeptics are fairly certain they have done it by adding artificial
fudge factors of dubious scientific merit  (I will confess to my embarassment that I have done exactly this when I have created industry models for a consulting client).

But one can also answer these questions about positive feedback loops from a
broader perspective.  Positive feedback loops are not unknown in nature
but are much rarer than negative feedback loops.  The reason is that
positive feedback loops lead to runaway processes that we seldom see in
nature.  Atomic fission is one of these thankfully rare process, and one can see that it is
probably lucky our universe is not populated with many such positive feedback
processes.  In our daily lives, we generally deal with negative
feedback:  inertia, wind resistance, friction are all negative feedback
processes.  If one knew nothing else, and had to guess if a natural
process was governed by negative or positive feedback, Occam's razor would say
bet on negative.  So, what about climate?  The evidence is equivocal,
but to be fair there is an example in our near universe of a runaway global
warming event - on Venus - though it occurred for reasons very different than
we are discussing with man-made climate change.

Negatives (and Positives) of Warming: While I have some trouble with
the science employed by global warming activists up to this point, it is on the
topic of the effects of global warming that the science really gets
flaky.  Now, certain effects are fairly likely.  For example,
hurricane activity will likely increase with warmer ocean temperatures.
Warmer ocean temperatures will also cause sea levels to rise, even without ice
melting, due to thermal expansion of the water.  And ice will melt, though
there is a really broad range of forecasts.

One reason that the ice
melting forecasts are hard is because while me may talk about the world
warming a degree, the world does not warm evenly.  Most climate models
show the most warming on dry winter nights  (Siberian winters, for
example, get a disproportionate share of the warming).  An extra summer
degree in Arizona would suck; an
extra winter degree in Siberia would probably be
welcomed, and would likely extend growing seasons.

And it is here that you get the greatest silence from warming
fanatics.  Because
it should be self-evident that warming can be good and bad.  Warming
can raise ocean levels and lead to droughts.  It can also extend growing
seasons and increase rain.  It all depends on where you are and what
forecast you are using.  The only common denominator is that most official
warming reports, such as those from the UN, spend an inordinate amount of time
discussing the negatives and very little time, if any, mentioning positive
offsets.  One of the reasons for this is that there is a culture in which
every environmental activist has been steeped in for years -- that man always
ruins nature.  That everything man does is bad.  Growth is bad.
Technology is bad.  To be fair, its not that many environmental scientists
are hiding the positive offsets, it's that they have been programmed for years to be
unable to recognize or acknowledge them.

Shouldn't We Fix it, Just to Be Safe:  If you get beyond the
hard core of near religious believers in the massive warming scenarios, the
average global warming supporter would answer this post by saying:
"Yes there is a lot of uncertainty, but you said it yourself: 
Though the doomsday warming scenarios via positive feedback in the climate
can't be proven, they are so bad that we need to cut back on CO2 production
just to be safe."

This would be a perfectly reasonable approach if cutting back on CO2
production was nearly cost-free.  But it is not.  The burning of
hydrocarbons that create CO2 is an entrenched part of our lives and our economies.
Forty years ago we might have had an easier time of it, as we were on a path to dramatically cut back on CO2 production
via what is still the only viable technology to massively replace fossil fuel
consumption -- nuclear power.  Ironically, it was environmentalists that
shut down this effort, and power industries around the world replaced capacity
that would have gone nuclear mostly with coal, the worst fossil fuel in terms
of CO2 production (per btu of power, Nuclear and hydrogen produce no CO2,
natural gas produces some, gasoline produces more, and coal produces the most).

Just halting CO2 production at current levels (not even rolling it back)
would knock several points off of world economic growth.  Every point of
economic growth you knock off guarantees you that you will get more poverty,
more disease, more early death.  If you could, politically, even
make such a freeze stick, you would lock China and India,
nearly 2 billion people, into continued poverty just when they were about to
escape it.  You would in the process make the world less secure, because
growing wealth is always the best way to maintain peace.  Right now, China can become wealthier from peaceful internal growth than it can from trying to loot
its neighbors.  But in a zero sum world created by a CO2 freeze, countries
like China would have much more incentive to create trouble outside its borders.  This
tradeoff is often referred to as a cooler but poorer world vs. a richer but
warmer world.  Its not at all clear which is better. 

One final  statement:  I have lost trust in the scientific
community on this.  There are just too many statements floating around like
this one that make it clear that getting people converted to the global
warming cause is more important than getting the science right.  Mann's
refusal to share his data so that his results can be validated (or invalidated,
as seems more likely now), the refusal
to consider any dissenting views in its "scientific" conferences,
the sloppy
science uncovered, the willingness to absurdly blame
every natural event on global warming  -- all these create the
impression that global warming is a religion with doctrines that can't be
questioned, rather than what it actually is -- a really, really chaotic and complex area
of science we have only just begun to understand.

For other reading, probably the first place to look is the Skeptical Environmentalist by Bjorn
Lomborg. Lomborg in this book has probably the best counter-case to the
enviro-disaster stories filling the media. He has become an object of absolute
hatred among the anti-growth anti globalization fanatics who have latched onto climate
change as the key to advancing their anti-technology and anti-capitalist
political agenda. The attacks on him have become nearly as edifying about what
drives the environmental movement as his book itself. The Economist has
a nice article about his book and about the wild-eyed furious reaction of
environmental activists to it. The Economist also editorializes
here, and you can follow all the criticism and response here on Lomborg's site.

The site junkscience.com is
invaluable, in fact with a better compendium of data on climate than most
climate sites.  A good
place to start is this article.

Other sources: This paper is
a good roundup of all the issues I have addressed. Cato has a lot of other
material here
as does the Heartland
Institute and at The
Commons.  A great post from Silflay Hraka that is much more eloquent
(and concise) than I am is linked here.

Update:  I have published a (free) more comprehensive guide to the skeptics
arguments concerning man-made global warming.  You can find the HTML version here and a free pdf download here.

Asymmetrical Information comments on Greg Mankiw by observing:

Harvard scores lowest in student satisfaction *and* enjoys the highest yield (%
of students admitted who attend) of any leading American university. How can the
same institution be so desirable and so disliked at the same time?

The data presented for is for the undergraduate school and my experience is with the graduate school of business, but I think some of my experience can still help answer this question.

At the time I attended, I was sure that the Harvard Business School (HBS) was the best place for me to attend.  I still think that is true.  First, it had (and has) a great reputation with both people hiring for jobs and the general public.  The Harvard diploma has power, power that hasn't lessened even 20 years later.  Second, it had a style that worked well for me personally.  I sat in on classes at other business schools, but HBS classes had an interactive, and often combative, style that I loved and thrived in.  Yes there was work, but the workload never was worse than my undergraduate school.  I would not change my decision.

That being said, while I have showered my undergraduate school with cash, Harvard has not gotten one dime from me.  Because as an institution, it sucked.  It had an incredible arrogance to it, often stating publicly that its customer was NOT the students, but was the businesses who hired its graduates and society at large.  And this was the attitude at the business school, which I was often told was the most student-friendly part of Harvard.  My college roommate Brink Lindsey apparently had a similar experience at Harvard Law, as he was part of a group that founded N.O.P.E., which stood for Not One Penny Ever (to Harvard).

At every turn, one ran into petty, stupid stuff that did nothing to contribute to the educational experience but were frustrating as hell.  The faculty was often arrogant and the administrative and housing staff uncaring. 

At the risk of sounding petty, I will share two examples.  These are small things, but are representative of hundreds of similar experiences over two years. 

• At winter break the first year, we were all given a "gift" of a coffee table book about Harvard.  Then, next spring, we all found a $100 charge on our spring term bill for this "gift"
• My Harvard dorm room had a broken heater in my second year.  It got so cold that ice formed on the inside of the windows.  After weeks of trying, we finally got a maintenance guy to come out.  He set a thermometer down in the center of the room and stared at it for ten minutes.  Then he picked it up and started to leave.  "Why are you leaving?" I asked.  He replied "Because its 53 degrees in here.  State law does not require us to fix the heating until it falls below 50."  I finally had to go to Walmart and buy several space heaters.  Several weeks later I was ticketed by the campus police for having a fire hazard -- too many space heaters.

I do not think it an exaggeration to say that had Harvard scoured every post office in the country for employees, it could not manage to provide worse customer service day-to-day.

And I think this is the answer to the paradox.  If you can tolerate the faculty arrogance, you can get a great education, but Universities are more than just a school.  For most students, Harvard is also their landlord, their only restaurant choice, their local police force, etc. etc.  And for all these other functions, they are terrible.

You know those towns along the highway where people joke "don't blink, or you'll miss it?"  Well, apparently I blinked and missed this story.  If the ice in a climatologist's bourbon & water melts faster than she expected, it gets a three-day spread in the New York Times, but this environmental good-new story (surely an oxymoron to most editors) seems to have been pushed to the back page last September:

The long-term health and environmental impacts of the 1986
accident at the Chernobyl nuclear power plant in Ukraine, while severe,
were far less catastrophic than feared, according to a major new report
by eight U.N. agencies.

The governments of Ukraine,
Belarus and Russia, the three countries most affected by radioactive
fallout from Chernobyl, should strive to end the "paralyzing fatalism"
of tens of thousands of their citizens who wrongly believe they are
still at risk of an early death, according to the study released Monday.

The 600-page report found that as of the middle of this year, the
accident had caused fewer than 50 deaths directly attributable to
radiation, most of them among emergency workers who died in the first
months after the accident.

In fact, even the "while severe" added into the first paragraph seems to be the last gasp of an editor unwilling to accept any environmental good news, since nowhere in the article is there any evidence published of any negative long-term effect at all except that caused to the mental well-being of local citizenry by the continual onslaught of media and governmental horror-predictions.

In fact, the article goes on to say:

Over the next four years, a massive cleanup operation
involving 240,000 workers ensued, and there were fears that many of
these workers, called "liquidators," would suffer in subsequent years.
But most emergency workers and people living in contaminated areas
"received relatively low whole radiation doses, comparable to natural
background levels," a report summary noted. "No evidence or likelihood
of decreased fertility among the affected population has been found,
nor has there been any evidence of congenital malformations."

In
fact, the report said, apart from radiation-induced deaths, the
"largest public health problem created by the accident" was its effect
on the mental health of residents who were traumatized by their rapid
relocation and the fear, still lingering, that they would almost
certainly contract terminal cancer. The report said that lifestyle
diseases, such as alcoholism, among affected residents posed a much
greater threat than radiation exposure.

The other major "fallout" seems to be massively wasted government spending:

Officials said that the continued intense medical monitoring of tens of
thousands of people in Ukraine, Russia and Belarus is no longer a smart
use of limited resources and is, in fact, contributing to mental health
problems among many residents nearly 20 years later. In Belarus and
Ukraine, 5 percent to 7 percent of government spending is consumed by
benefits and programs for Chernobyl victims. And in the three
countries, as many as 7 million people are receiving Chernobyl-related
social benefits.

Sounds like post-Katrina proposals.  We have already seen more level-headed analysis debunk similar horror stories (remember "toxic soup") in New Orleans.  I wonder what a sober analysis of the real long-term health effects around the PG&E site that Erin Brockovitch made her name on would reveal?  When I lived in St. Louis, we had a local meteorologist we used to joke had "accurately predicted twelve of the last three blizzards".  Environmentalists who perplexedly scratch their heads as to why everyone does not yet fully buy into global warming should move past their "everyone is in the pay of the oil companies" explanation and maybe consider for a minute that their panicked prediction of twelve of the last three environmental disasters may be part of the explanation as well.

By the way, what really killed nuclear power was the costliness of the ridiculous regulatory regime.  In a prior post, I suggested an alternative regulatory regime, copied from airlines (see, we libertarians can sometimes hold our nose and actually make a regulatory reform proposal short of "throw it all out").  Reason's Hit and Run points to an example of those on the left reconsidering nuclear power.

You know how when you grew up, your parents and grand-parents always said stuff like "I remember when I was a kid, we didn't even have X", where X was airplanes, or TV's or ice or whatever.  I actually found myself having one of those moments in the OfficeMax store today.  I remember when I got my first hard drive for my IBM PC in the very early 80's.  It was 10MB, cost about $500, and my one thought at the time was "I'll never be able to fill up this thing".

Today at the office supply store at the register I made an impulse purchase for a new USB memory key.  My son stole mine to use to take stuff back and forth to school, and I wanted a larger capacity drive anyway.  So here I was buying a 1GB key, with 100x the storage of that first hard drive in a package about 1/100 of the size of that hard drive, and I was buying it at the cash register from a rack next to the gum.  Pretty cool.

However, I am not going to let scientists totally off the hook.  I am still waiting for my hover car, my jet pack, and my vacation on the moon, which I expected to have long before now.

In the beginning,  I tried to write a blog about my day to day experiences as a small business person.  That lasted about a day, mainly because I have the attention span of a 7-year-old boy mainlining Hershey Bars.  I still blog a lot about running a small business, but I also comment on political trends, mainly from a libertarian point of view, and anything else that happens to strike my fancy that day.

However, with Google out there, I have lost even more focus and control of my blog's positioning.  A lot of my traffic is Google hits, and it turns out there are two particular searches that drive a non-trivial portion of my traffic.  That means for many readers, my blog is defined by these two topics:

• Pocket Doors
• Spanking

Yes, call me the Pocket Door and Spanking Blog now.  LOL.  Anyway, if only to reinforce my strong Google rankings on these meaningful topics, here is how I became the Pocket Door and Spanking Blog:

Pocket Doors and My Manhood  (December, 2005)

Our bathroom has a pocket door to save space - that's one of those doors that slide on a hidden rail in and out of the wall.
From time to time, usually because my kids go slamming into it, the
door comes off its rails and gets jammed, which is a problem as it can
bottleneck some very critical facilities.

The first time this happened, I tried to get it back on its track,
but I just could not.  The track is up in the wall and it is almost
impossible due to the lack of clearance to do anything with it.  I
checked in the Yellow Pages and saw there was actually a company that
specialized in pocket door repairs, so I called them out.  Well, Joe
(or whoever) shows up with his little tool kit, looks at the door for a
second, grabbed it in a certain way, and then gave it a quick jerk -
kabam - and it was back in its tracks.  It took him like 5 seconds. 

Well, there I stood, completely unmanned, right in front of my
laughing wife and family, by Joe the visible butt-crack guy.  Bummer.

Since that time, I have had the door come untracked two or three
times.  Thinking to save me further embarrassment, my wife tends to ask
any passing stranger to come in and fix it.  I can sit there for hours
fighting the thing, and then my wife brings in the guy painting the
house - kabam - fixed.  Next time she brought in the 60+ year old sales
guy who happened to be there - kabam - fixed.  I swear, if Paris Hilton
was dropping by for a visit she could probably fix that damn door.  It
is humiliating.

Well, this time I would not allow my wife get someone else to fix
it.  Every night, for about 10 minutes, I would take my innings with
the door, struggling to do what everyone else seemed to have learned at
birth.  I actually suggested to my wife that we should call out a
contractor and tear the thing out and install a real door.  She
suggested instead that she could have our 13-year-old baby sitter come
in from the other room to fix it.  Finally, tonight, when I was about
to give up, I tried holding it in a slightly different way and - Kabam
- fixed.  God I feel great.  My manhood is restored and I am at the top
of the world.

Spanking Employees  (November, 2005)

Well, just when you think you have seen every way to screw up in a small business, there comes this story.

The owner of a shaved ice business was arrested after two employees claimed he spanked them for making mistakes at work.

And more...

One
of the women told police that on her first day at the Tasty Flavors Sno
Biz, Levengood made her sign a statement that said: "I give Gene
permission to bust my behind any way he sees fit."

Hat tip to Jim Rome, as I first heard this on his radio show, and to the Mises Institute,
of all places, where I found the link.  This story has been out and
about for a while, but I wanted to give it a few days to make sure it
was not a hoax.

To make this more bizarre, I did a Google search to see if
anyone had called this out as a hoax, and found that there have been
many similar stories in other places, including here and here.

Sigh.  Oh well, I guess a weird identity is better than no identity at all.

After a number of posts on global warming, several of my friends and family have sent me various links and tracts and articles, apparently concerned about me as a Kyoto "unbeliever".  It reminds me a lot of my neighbor giving my wife religious pamphlets when she found out we didn't go to church on Sunday.  Jerry Pournelle has a good series of posts about getting roughly the same reaction. 

So here is a bit of advice:  First, keep sending me anything thing that has science in it, I always enjoy reading it.  Second, if you are going to send me climate science, make sure you understand where my agnosticism lies:  I don't need more articles saying "see, the world has warmed, therefore we need the Kyoto treaty" or "look at the CO2 rise at Hilo station".  In my mind, there are five logic steps you need to make to justify Kyoto-type emissions limitations.   Everyone sends me proof of the first two steps, but I seldom see science on the last three, which are the most problematic.  Here they are, and where my current thinking is on each:

1.   Is the world warming?  The answer is yes, though ground-based measurements influenced by urban heat islands may be over-estimating the rise, despite corrections.  Also, one needs to remember that some of the warming occurred in the early parts of the century, where man-made CO2 is unlikely to be to blame. 

By the way, be very careful of advocates' graphs - often the time scale is "managed".  Someone sent me this link, of rising temperatures in Central Park.  Unfortunately, the graph is carefully selected, and here is the graph with all the data (same data source) shown.  I have seen the same game played with this chart several times, showing only the data since 1965, which obviously would tell a very different story.  All that being said, I am still convinced the earth is warming some, but what does it tell you when organizations play such exaggeration games with the data - are they being objective scientists or advocates? 

2.  Is the warming due to man-made CO2?  The answer is partially, though perhaps not as much as global-warming activists want to believe.  Yes, man-made CO2 has almost certainly increased CO2 concentrations in the atmosphere, but solar activity has also been at a cyclical peak in this century, and many point to this activity as another contributor to warming.  Also, something other than man-made CO2 drove a half-degree warming early in the century, so whatever caused that warming may well be contributing to warming in the second half of the century (unless you want to take the dangerously untenable position that whatever drove early century warming stopped at the same time that CO2 started having an effect).  Finally, there are still arguments about the quality of the statistical analysis in looking at long term climate trends.

3.  How much will man-made CO2 raise temperatures in the future?  My answer is some, but not nearly as much as models predict.  First, recognize that funding levels for climate research today tend to rise in proportion to how dire the forecast is, so organizations have a financial incentive to over-predict.  Second, when current models are applied to history, they over-predict temperature rise.  This leads me to worry that they may be over-predicting for the future as well.   Yes, they claim to have "corrected" this problem, but in fact they just added fudge factors -- whole fortunes have been lost on Wall Street this way.  Third, and the one thing I can confirm from my own knowledge and analysis, climate models GROSSLY over-estimate man-made CO2 production in the future due to enormously flawed economic models.  I spend a lot more time disecting these mistakes here, but to summarize, the models take the most inefficient nations, assume little efficiency improvements, then grow their economies like crazy:

Because of this economic error, the IPCC scenarios of the future also suggest that relatively poor developing countries such as Algeria, Argentina, Libya, Turkey, and North Korea will all surpass the United States [in terms of GNP]

4.  What is the net cost to the world of global warming?  This is where climate science really begins to break down.  The answer is that, scientifically, we don't know.  We don't even know if it is net bad - warming may be net beneficial.  The "bad things" claims have tended to have a "day after tomorrow" sloppiness to them, but the main bad things cited are rising sea levels and increases in violent weather patterns.  Note that the second is entirely unproven, and, no matter what any media article says, we have not yet seen any increase in violent weather recently -- the data so far does not support it.  As to rising sea levels, there is more science behind the claim but again, we have not yet seen any evidence of it.  Most climate scientists will admit that the majority of the warming will occur on winter nights in the coldest regions (e.g. lots of warming of Siberian winters).  But arctic ice melt in sea level rise scenarios mainly occurs during summer days.  How can this be reconciled?  In fact, NASA data shows little or no warming to date in Antarctica or in the Arctic, despite the fact that models say that it should show the most (and therefore the most melting ice).

Beyond the lack of proof is the fact that most global warming activists don't consider or don't want to admit that there are positive effects.  For example, warming would lengthen growing seasons in most areas, potentially increasing food production.  For example, the Cato Institute reported:

The weather can, of course, be too warm, but that is unlikely to become a major problem if the globe warms. Even though it is far from certain that the temperature will rise, the Intergovernmental Panel on Climate Change (the U.N. body that has been studying this possibility for more than a decade) has forecast that, by the end of the next century, the world's climate will be about 3.6° Fahrenheit warmer than today and that precipitation worldwide will increase by about 7 percent. The scientists who make up this body also predict that most of the warming will occur at night and during the winter. In fact, records show that, over this century, summer highs have actually declined while winter lows have gone up. In addition, temperatures are expected to increase the most towards the poles. Thus Minneapolis should enjoy more warming than Dallas; but even the Twin Cities should find that most of their temperature increase will occur during their coldest season, making their climate more livable.

5.  What is the Cost-Benefit trade-offs of mandated CO2 limitations?  Again, no one knows and if there is any good science on this, I have not seen it.  You can guess that if we have not even figured out if warming is net-bad or net-good, we probably don't have a good handle on cost-benefit trade-offs of treaties like Kyoto.  Even without this trade-off analysis, though, we can come to a few conclusions about Kyoto:

• Even global warming activists admit that Kyoto will at best reduce temperatures 50 years from now by something like a tenth of a degree.
• Whatever the benefit of reducing CO2 is, Kyoto takes one of the highest cost approaches (see study here).  The main reason is fairly obvious based on the laws of diminishing returns:  The cheapest place to reduce emissions is in the most inefficient countries, and vice versa.  But Kyoto focuses all its reductions on the most efficient industrialized countries, so it is seeking reductions in the highest possible cost locations.
• Kyoto is mainly a slam-America treaty.  The way it was constructed, with its 1990 reference date, was cleverly chosen to put most of the burden on the US.  The US has experienced fabulous growth since 1990, while Japan and European nations have experienced slow growth as well as structural changes that make the target artificially easy to reach for them (see more here).   Fast growth developing countries are excluded from the treaty entirely.

So here is my point -- it is possible to believe in the theory of man-made CO2 driving temperature increases and still be skeptical of government action on emissions.  Jerry Pournelle has a good series of posts on the same topic. 

For other reading, probably the first place to look is the Skeptical Environmentalist by Bjorn Lomborg. Lomborg in this book has probably the best counter-case to the enviro-disaster stories filling the media. He has become an object of absolute hatred among the anti-growth anti globalization fanatics who have latched onto climate change as the key to advancing their anti-technology and anti-capitalist political agenda. The attacks on him have become nearly as edifying about what drives the environmental movement as his book itself. The Economist has a nice article about his book and about the wild-eyed furious reaction of environmental activists to it. The Economist also editorializes here, and you can follow all the criticism and response here on Lomborg's site.

Other sources: This paper is a good roundup of all the issues I have addressed. Cato has a lot of other material here as does the Heartland Institute and at The Commons.

UPDATE:

A great post from Silflay Hraka that is much more eloquent (and concise) than I am is linked here

So what does valet parking, soft drinks, and firewood have in common?  More in a second.  First, some background.

We have had a problem over the last few years in our California campgrounds.  We sell a lot of firewood to campers, usually in bags of 6-8 sticks.  We are having difficulties getting a good, inexpensive firewood source in the Owens Valley.  We can find a bunch of people who will deliver stacks of firewood by the cord for a very good price, but only one person in the valley bags the wood.  As a result, the bagging step alone is effectively costing us between $1 and $2 a bundle, which is a lot for something we sell for $5-$6. 

In kicking the problem around, we considered what is becoming an increasingly common approach - if bagging is labor intensive and costly, lets see if we can outsource that step to our customers.  Outsourcing to your customers has been around for a while, but has gotten more popular of late.  Many furniture and equipment makers have been doing this for years, by outsourcing final assembly to customers.  While some of this is to reduce shipping costs, part of the benefit to manufacturers is that they save on assembly labor.

Service industries have started to get into the act of late.  Banks have been outsourcing teller functions for years via ATM's.  Most fast food restaurants have outsourced soft drink cup filling to the customers.  Grocery stores (and now Home Depot) have hopped on the bandwagon, providing self-service checkout for those who don't want to wait in line.

What all these examples have in common is that they seem to meet with customer acceptance if they provide some sort of value to the customer(short-circuiting lines, easier drink refills, the right amount of ice in the cup) , and not just cost-savings to the company.

Which brings me to the examples that really irritate me - of companies outsourcing their payroll to me.  [Note, I am a libertarian -- please do not interpret the following as a call for government action!]  Tipping, in its purest form, is a way to reward exceptional (meaning - beyond the standard or expected) service.  Unfortunately, restaurants and other service establishments have twisted this act of reward and generosity into having customers pay the wages of their staff.  Restaurants are simultaneously increasing tipping expectations (from 15% to 20%+) while requiring tips on more and more occasions by building them automatically into the bill.

The event that brought my irritation to a boil the other day actually happened valet parking my car at a restaurant.  As background, the establishment charged $4 to valet park your car.  Now, I am not a socialist, so I accept that value is not driven by cost but rather by what I am willing to pay for it, and I was willing to pay $4 to avoid having to walk a few blocks from the free lot  (those of you from Boston or NY are wondering what the fuss is about -- a valet parking charge of any amount is virtually unprecedented in Phoenix, at least until recently).

So I paid my $4, and then I saw the sign:

"Our employees work for tips"

What?  You mean I just paid your company $4 for what amounts to about 5 minutes of labor, and now you are telling me that in addition, I need to pay your employees' wages for you too?  This is pretty nervy - I mean, other than a percentage concession payment they are probably making to be the parking company at that location, what other costs do they have?  I didn't want to hurt the young guy actually doing the parking, but for the first time in years I didn't tip the valet.  That little sign turned, for me, an act of goodwill into a grim obligation, extorted from me by guilt. 

Which brings me back to firewood.  In outsourcing bagging to the customer, I did not want to tick off our customers like I had been angered by similar steps, so I set two criteria for my managers and any plan they came up with:

• It had to save a substantial amount of money, some of which we could pass back to customers as a price savings
• It had to offer the customer more value - a better product somehow.

The plan my managers hit on was to purchase a number of small milk crates that customers could fill with wood for the same price as the old bag.  These crates would hold a bit more than the old bag, so customers can get more wood for their money.  In addition, customers can pick out their own pieces of wood from the stack.  This is actually something that has been requested in the past - some customers complained the bags had too many small sticks, some complained they had too many large sticks.  Now people can get what they want.  We will try this out in a few sites to see what customer reaction is, and, perhaps more importantly, to see if we can hold on to our milk crates without them walking away.

Courtesy of Nature Noted, comes this article on two enormous blocks of ice set to collide in the next week in Antarctica.

As the Nasa site linked above puts it:

It is an event so large that the best seat in the house is in space: a massive iceberg is on a collision course with a floating glacier near the McMurdo Research Station in Antarctica. NASA satellites have witnessed the 100-mile-long B-15A iceberg moving steadily towards the Drygalski Ice Tongue. Though the iceberg's pace has slowed in recent days, NASA scientists expect a collision to occur no later than January 15, 2005.

Well, just when you think you have seen every way to screw up in a small business, there comes this story.

The owner of a shaved ice business was arrested after two employees claimed he spanked them for making mistakes at work.

And more...

One of the women told police that on her first day at the Tasty Flavors Sno Biz, Levengood made her sign a statement that said: "I give Gene permission to bust my behind any way he sees fit."

Hat tip to Jim Rome, as I first heard this on his radio show, and to the Mises Institute, of all places, where I found the link.  This story has been out and about for a while, but I wanted to give it a few days to make sure it was not a hoax.

To make this more bizarre, I did a Google search to see if anyone had called this out as a hoax, and found that there have been many similar stories in other places, including here and here.