Coyote Blog

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. 

All these years of writing about climate change, and I always have claimed that I was not in the pay of any interested industry groups.  Well, I guess I lied.  It appears "Big Recreation" is lobbying against greenhouse gas controls.

Sen. James Inhofe (R-Okla.), Ranking Member of the Environment and Public Works Committee, said: 

"The
recreation industry's true threats come not from climate change --
which has always changed and will always change -- but from the
so-called global warming "˜solutions' being proposed by government
policymakers. Misguided efforts to "˜solve' global warming threaten to
damage the travel and recreation industry and consequently threaten the
American dream."

This is probably true, though the ski resort guys don't agree.

For those who don't know, several years ago I quit both boneheaded Fortune 50 life and boneheaded startup life to run my own recreation business, where I am trying to push a vision of, and make a little money from, privatization of public recreation.  I am actually fairly well insulated from gas price shocks, though by accident rather than thought-out-in-advance strategy.  We have mainly taken over government recreation facilities where the customer base is local weekend traffic (rather than say cross-the-country-to-see-old-faithful travelers).   This is really by accident, because these facilities took less investment than the big national attractions.  As it turns out, when gas prices go up, we actually do a bit better, because people still want to camp and use their RV, but they do it 100 miles from home rather than 1000.

By the way, I am working on a skeptics primer to anthropogenic global warming, which is why blogging has been light.  If you'd be willing to read and comment on a pre-release version, email me and I will put you on the list for a pdf which will be coming in a week or so.  In the mean time, some of my previous work is here

This is an outstanding post that a reader sent me that offers a number of climate scientists in their own words taking issue with the climate consensus on CO2-driven anthropogenic global warming.  I won't convince you that man-made CO2 is not one cause for warming -- at this point in the science's development, that would be as big a mistake as declaring AGW theory "settled."  However, for those who get beaten about the head with "consensus" every time you ask a skeptical question about AGW, you should enjoy this article.  This is just one of the 13 vignettes on newly minted skeptics the author highlights:

Botanist Dr. David Bellamy, a,
recently converted into a skeptic after reviewing the science and now
calls global warming fears "poppycock." According to a May 15, 2005 article
in the UK Sunday Times, Bellamy said "global warming is largely a
natural phenomenon.  The world is wasting stupendous amounts of money
on trying to fix something that can't be fixed." "The climate-change
people have no proof for their claims. They have computer models which
do not prove anything," Bellamy added. Bellamy's conversion on global
warming did not come without a sacrifice as several environmental
groups have ended their association with him because of his views on
climate change. The severing of relations came despite Bellamy's long
activism for green campaigns. The UK Times reported Bellamy "won
respect from hardline environmentalists with his campaigns to save
Britain's peat bogs and other endangered habitats. In Tasmania he was
arrested when he tried to prevent loggers cutting down a rainforest."

Here is a copy of the petition sent to the Canadian government which several of the people in the article refer to.  One taste:

Observational evidence does not support today's computer climate
models, so there is little reason to trust model predictions of the
future. Yet this is precisely what the United Nations did in creating
and promoting Kyoto and still does in the alarmist forecasts on which
Canada's climate policies are based. Even if the climate models were
realistic, the environmental impact of Canada delaying implementation
of Kyoto or other greenhouse-gas reduction schemes, pending completion
of consultations, would be insignificant. Directing your government to
convene balanced, open hearings as soon as possible would be a most
prudent and responsible course of action....

While the confident pronouncements of scientifically unqualified environmental groups may provide for sensational headlines, they are no basis for mature policyformulation.
The study of global climate change is, as you have said, an "emerging
science," one that is perhaps the most complex ever tackled. It may be
many years yet before we properly understand the Earth's climate
system. Nevertheless, significant advances have been made since the
protocol was created, many of which are taking us away from a concern
about increasing greenhouse gases. If, back in the mid-1990s, we knew
what we know today about climate, Kyoto would almost certainly not
exist, because we would have concluded it was not necessary....

"Climate change is real" is a
meaningless phrase used repeatedly by activists to convince the public
that a climate catastrophe is looming and humanity is the cause.
Neither of these fears is justified. Global climate changes all the
time due to natural causes and the human impact still remains
impossible to distinguish from this natural "noise." The new Canadian
government's commitment to reducing air, land and water pollution is
commendable, but allocating funds to "stopping climate change" would be
irrational. We need to continue intensive research into the real causes
of climate change and help our most vulnerable citizens adapt to
whatever nature throws at us next.

It is signed by scientific no-names like Freeman Dyson and Dr. Richard S. Lindzen, Alfred P. Sloan professor of meteorology, Dept.
of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute
of Technology

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)

I promise, cross my heart, this is my last post on climate change for a while.  I thought my series of posts last week about the funny math of carbon offsets was the last, but Joe Miller at Catallarchy wrote something that caused me some introspection:

Just one caveat, though: I'm really, seriously, profoundly uninterested
in your skepticism about man-made global warming. Personally, I think
that the debate is just about as fruitful as a discussion of the
relative merits of evolution and Genesis as models of the origins of
the universe. It's called scientific consensus, people. You seem to
like it well enough for every other subject. And even if that
overwhelming scientific consensus turns out to be wrong, it's not like
a debate here is going to help with that. When scientists are wrong,
it's up to, you know, like, other actual scientists to settle
the question. A bunch of non-scientists googling studies that say what
we like them to say isn't accomplishing much, really.

Certainly I have always been in favor of facts and science over hysteria.  I criticized the rampant breast implant litigation in the face of science that showed no real long-term harms.  Ditto vaccinations.  So am I being a Luddite by, as an amateur, being skeptical of the scientific "consensus" on global warming?  Certainly climate change hawks want to paint my positions as "holocaust denial."  I had a few thoughts:

• For what it is worth, I have actually read much of the 2001 IPCC climate report (not the management summary, which is a worthless political document, but the report itself).  Courtesy of JunkScience.com, who has posted some of the 2007 report, I have read key parts of that report as well.  So I have at least informed myself beyond random Google searches.  My original university training was as a scientist, and later an engineer, though neither in climate (physics and mechanical engineering).
• The media has been known to declare a consensus ahead of its actual existence.  One example that comes to mind is a recent letter that a number of economists wrote supporting a Federal minimum wage increase, which much of the media spun into a "consensus" among economists that a minimum wage increase would be desirable and would not reduce employment.  I don't know Mr. Miller, but my bet is that some of the folks at Catallarchy might dispute this particular scientific consensus.
• To even imply that there is a single consensus on something as complex and multi-faceted as anthropomorphic global warming is facile.  I will take the movie "An Inconvenient Truth" as a fair representation of what the media perception of the consensus is  (the IPCC report actually does not agree in full, but we will get there in a minute).  Taking that movie as our straw man, the "consensus" or hypothesis is as follows:

1. The world has been warming for a century, and this warming is beyond any historical cycles we have seen over 1000 years  (ie, the hockey stick)
2. The last century's warming is almost all due to man's burning of fossil fuels and other releases of greenhouse gasses
3. In the next 100 years, CO2 produced by man will cause a lot more warming
4. Positive feedbacks in the climate, like increased humidity, will act to triple the warming from CO2
5. The bad effects of warming greatly outweigh the positive effects, and we are already seeing them today (polar bears dying, glaciers melting, etc)
6. These bad effects, or even a small risk of them, easily justify massive intervention today in reducing economic activity and greenhouse gas production

I believe this is a mostly fair representation of the media reporting of the scientific "consensus", with the exception that the media never really goes into step #4, and assigns all the blame for 6-8 degree temperature rise forecasts to CO2.  But this split between #3 and #4 is important to understand the science at all, and is included in the IPCC report, so I will make it. 

This is a complicated string of logic, with multiple assumptions.  I hope you see why declaring a scientific consensus on all points of this hypothesis is facile.  So where is there a scientific consensus on all of this?  My interpretation from the recent IPCC report and other sources is:

1. The world has been warming for a century, and this warming is beyond
   any historical cycles we have seen over 1000 years  (ie, the hockey
   stick)   There is a strong consensus on the first half.  We can argue about urban heat island corrections and ground vs. satellite all day, but the earth has pretty clearly warmed for a hundred years or so, after cooling before that.  The second half of the proposition is trickier.  The 2001 report relied on the Mann hockey stick to make the point that the 20th century is not just warmer but uniquely warmer.  I sense the 2007 report backing off this -- the Mann analysis has a lot of problems, and ongoing climate research continues to point to the great variability and cyclicallity of climate over time.  There is too much historical evidence, for example, of a warm middle ages for Mann to dismiss it with a few tree rings.
2. The last century's warming is almost all due to man's burning of fossil fuels and other releases of greenhouse gasses.   The 2001 IPCC report implied about half of the century's warming was man-made.  The new report seems to put more of the blame on man.  My sense is this will move over time back to half and half -- the evidence today of increased solar activity is becoming too strong to ignore as a cause along with man-made CO2.  However, I recognize right now that I am out of step with the IPCC and perhaps the "consensus" on this.
3. In the next 100 years, CO2 produced by man will cause a lot more warming.  CO2 production by man will cause more warming.  How much is the subject of models, which any economist or businessperson can tell you are notoriously flaky.  However, here is one fact that is part of the scientific consensus but you never hear in the media -- the relationship between atmospheric CO2 concentration and warming is a diminishing return.  In other words, the next doubling of CO2 in the atmosphere will have less impact on temperatures than the last doubling.  At some point, the effect of CO2 maxes out, and further increases in CO2 have no effect on temperatures.  My reading of the newest IPCC seems to imply that if the models predict about 6 degrees of warming over the next 100 years, of which about 2 is directly from CO2, while the rest are from positive feedbacks (discussed next)
4. Positive feedbacks in the climate, like increased humidity, will act to triple the warming from CO2.  OK, this strikes me as the key point in the scientific consensus.  Hypothesized positive feedback loops in the climate are what take the IPCC models from results that are warmer but probably manageable to results that appear catastrophically warmer.  Their models assume that as the world warms a bit from CO2, other effects take hold, and the world will warm even more.  For example, they posit that if the world is warmer, more water evaporates into water vapor in the atmosphere, which is a strong greenhouse gas, which accelerates the warming.  I think it is absurd to say there is a consensus on this point, which is adding 2/3 or more of the warming.  The notion of positive feedbacks in nature offends my intuition --  there are just not that many such processes in nature, or else nothing would be stable -- but then again Einstein's intution was offended by quantum mechanics and he was wrong.  However, using the IPCC's own findings (starting in section 8.6 here) the IPCC admits to there not even being a consensus on the sign (ie if it is positive or negative feedback) of what they describe as by far the strongest feedback process (cloud cover)!  I don't know how you can declare a consensus if you admit you don't even know the sign of the largest effect.
5. The bad effects of warming greatly outweigh the positive effects,
   and we are already seeing them today (polar bears dying, glaciers
   melting, etc)  It would be absurd to declare a consensus here because no one has really done much definitive work.   Most folks, including me, presume that since substantial warming would take us beyond the temperature range for which our bodies and our civilization has been adapted, the net effect would be bad.  But there are positive offsets to the negative effects (e.g. oceans rising) that you never really hear about in the press (longer growing season, for one) but which are in the IPCC report.  Climate scientists themselves have admitted there is no consensus on what effects that we are seeing today are due to warming.  Part of Antarctica (about 2%) shown in Al Gore's movie is warming, but most scientists now think that this may be due to cyclical variations in ocean currents, while most of Antarctica has actually been cooling of late.  Greenland is warming, but glaciers may not be receding as fast as once feared.  Polar bear populations, despite reports to the contrary, are increasing.
6. These bad effects, or even a small risk of them, easily justify
   massive intervention today in reducing economic activity and greenhouse
   gas production.  Many climate scientists express an opinion on this, often definitively, but if one argues that I am not qualified to test the consensus as a layman on global warming, then certainly climate scientists are far from qualified in drawing any conclusions on this topic.  The effects of a worldwide rollback on CO2 production at current technologies could be catastrophic, particularly for a billion people in India and China just on the verge of emerging from poverty.  Even in some of the most dire forecasts for warming, it is a very open question with little consensus as to whether a cooler but poorer world is better.  In fact, one can argue that even the pious Kyoto-signing countries are voting with their actions, rather than their words, on this issue, since they have resisted taking the hard economic steps necessary to meet their targets.

OK, that is more than I meant to write.  My point is that the word consensus is an absurd word to apply to the topic of anthropomorphic global warming.  Some things we understand pretty well (the world is warming, in part due to man-made CO2) and some we understand less well (the effect of feedback loops).  And some issues, like whether the harms from climate change are worth the cost of avoiding them, are entirely outside the purview of climate science.

Update: Strata-Sphere has a funny bit of related snark:

Global warming on Neptune's moon Triton as well as Jupiter and Pluto, and now Mars has some scratching their heads over what could possibly be in common with the warming of all these planets....

I still don't know. Could there be something in common with all the
planets in our solar system that might cause them all to warm at the
same time?

On a serious note, he has some nifty graphs of historic earth temperature reconstructions (including Mann) vs. sunspot activity reconstructions (sunspot activity generally being a proxy for solar output).  Short answer:  Sunspot activity at historical highs, at the same time as historical highs in temperature. 

Regular readers will know I am skeptical that anthropomorphic global warming and its effects will be as bad as generally predicted.  However, if I can work around this bias, I would like to cast the issue as neutrally as I can:  Man-made CO2 will likely cause the world to warm some, and the negative effects of this for man are likely higher than the positive effects.  Under some assumptions, these net negative effects of man-made warming could be astronomical in cost, while under other assumptions they will be less so.  Against this variable outcome, efforts to substantially reduce CO2 production world wide and prevent further increases of atmospheric CO2 concentrations will carry a staggering cost, both in dollars and the inevitable social effects of locking developing countries into poverty they are just now escaping (not to mention loss of individual liberty from more government controls).

The political choice we therefore face is daunting:  Do we pay an incredibly high price to abate an environmental change that may or may not be more costly than the cure?  Reasonable people disagree on this, and I recognize that I may fall in the minority on which side I currently stand on (I think both warming and its abatement costs are overblown, mainly because I have a Julian-Simonesque confidence in man's adaptability and innovation).

Against this backdrop, we have Kevin Drum declaring "More good news on the global warming front:"

Seeking to shape legislation before Congress, three major energy trade
associations have shifted their stances and decided to back mandatory
federal curbs on carbon dioxide and other man-made emissions that could
accelerate climate change.

Here is my news flash:  Having some Washington lobbying organizations switch which side of this incredibly difficult trade off they support is not "good news."  Good news is finding out that this trade off may not be as stark as we think it is.  Good news is finding some new technology that reduces emissions and which private citizens are willing to adopt without government coercion (e.g. sheets of solar cells that can be run out of factories like carpet from Dalton, Georgia).  Or, good news is finding out that man's CO2 production has less of an effect on world climate than once thought.  Oddly enough, this latter category of good news, surely the best possible news we could get on the topic, is seldom treated as good news by global warming activists.  In fact, scientists with this message are called Holocaust deniers.  I wonder why?

Update: LOL

Please stop tell me that I have no right to question Al Gore when he wants to take over the world economy to his own ends.  And please stop telling me that catastrophic man-made global warming is now beyond question:

One of the many disturbing aspects of global warming hysteria is the
way moonbats who use it to promote their ominous political agenda
insist on a consensus that simply does not exist. A recent survey
of more than 12,000 environmental scientists and practitioners by the
National Registry of Environmental Professionals shows that despite the
hysteria and considerable pressure to conform to the "correct" view,
many scientists are choosing skepticism over the safety of the herd.

The survey found that:

• 34% disagree that global warming is a serious problem;
• 41% disagree that warming trends "can be, in large part, attributed to human activity";
• 71% disagree that human activity has significantly contributed to hurricanes;
• 33% disagree that the US government is not doing enough about global warming;
• 47% disagree that international agreements such as the preposterous
  Kyoto Protocol provide a useful framework for addressing global climate
  change.

There are good reasons to believe in some man-made global warming, but there are very good reasons to doubt it will be as catastrophic as portrayed in the media, and very, very good reasons not to hand over the throttle of the world economy to environmental groups in anticipation of such uncertain events.  My position on the skeptical middle ground on climate change is here.

The word "censorship" is used all-too-often in this country.  I take a much more narrow definition of censorship.  In my mind, only the government can be guilty of true censorship, which I define as using the coercive power of government to prevent certain forms of speech.  By even this narrow definition, the recent threats against Exxon by Senators Jay Rockefeller and Olympia Snowe come awfully close to censorship:

We reprint the full text of the letter here,
so readers can see for themselves. But its essential point is that the
two Senators believe global warming is a fact, and therefore all debate
about the issue must stop and ExxonMobil should "end its dangerous
support of the [global warming] 'deniers.' " Not only that, the company
"should repudiate its climate change denial campaign and make public
its funding history." And in extra penance for being "one of the
world's largest carbon emitters," Exxon should spend that money on
"global remediation efforts."

The
Senators aren't dumb enough to risk an ethics inquiry by threatening
specific consequences if Mr. Tillerson declines this offer he can't
refuse. But in case the CEO doesn't understand his company's jeopardy,
they add that "ExxonMobil and its partners in denial have manufactured
controversy, sown doubt, and impeded progress with strategies all-too
reminiscent of those used by the tobacco industry for so many years." (Our emphasis.) The Senators also graciously copied the Exxon board on their missive.

This
is amazing stuff. On the one hand, the Senators say that everyone
agrees on the facts and consequences of climate change. But at the same
time they are so afraid of debate that they want Exxon to stop
financing a doughty band of dissenters who can barely get their name in
the paper. We respect the folks at the Competitive Enterprise
Institute, but we didn't know until reading the Rockefeller-Snowe
letter that they ran U.S. climate policy and led the mainstream media
around by the nose, too.

While I tend to believe that the warming camp is correct that manmade CO2 is creating or will create some global warming, there are a lot of very very good reasons to be skeptical of the magnitude of their warming estimates and their hysterical calls for massive government intervention in the world economy.  I call this the skeptical middle ground on climate.  (Update: more reasons to be skeptical of current "consensus" models here).  A skeptics guide to An Inconvenient Truth is here.

Ronald Bailey makes a plea for free scientific inquiry in response to Dave Roberts proposal vis a vis climate skeptics.  Mr. Roberts said, in part:

When we've finally gotten serious about global warming, when the
impacts are really hitting us and we're in a full worldwide scramble to
minimize the damage, we should have war crimes trials for these
bastards"”some sort of climate Nuremberg

Oh goody, yet another reason I will be put up against the wall come the progressive revolution.  I would give Mr. Roberts a helpful suggestion:  A better analog for prosecuting people over their scientific beliefs would be the Catholic Church's various attempts to stamp out heresy, including their prosecution of Galileo for his views that the earth orbits around the sun, rather than vice-versa.

My views on the reasonable skeptical middle ground on climate change here. (and more here)

Besides, I would argue that progressives like Mr. Roberts willful ignorance of the science of economics has been far more destructive than potential scientific misreadings of global warming.

A week or so ago, I tried my best to lay out what I thought was a reasonable position on man-made global warming, while at the same time criticizing some of the Al Gore-type over-hype that's out there as climate change evangelists, to put it charitably, get out ahead of the current science. 

In a similar manner, I thought this article by Ron Bailey does a pretty good job at trying to find some stable ground in the climate change debate.

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.

Its probably time for another once-every-six-months update on global warming.  In this post I will address the current leading climate intervention position, which is:  Even if we don't understand global warming fully, the time to take massive action is now, before the process builds momentum (similar to the notion that it is easier to deflect a meteor away from earth when it is millions of miles away, rather than right on top of us).  The potential downside of global warming, it is argued, is too high to justify waiting until we are sure.   

While I find arguments that attempt to challenge the current global warming orthodoxy in any way tends to get one labeled a Luddite not worth listening to, giving one the feeling of being a southern Baptist advocating creationism in a room full of Massachusetts Democrats, I will once again try to refute this need to immediate and massive intervention.

The shorthand I use for my argument against intervention is "creating a cooler but poorer world".  In a nutshell, given current technology and likely government intervention approaches, slowing global warming almost certainly entails slowing world growth.  And while the true cost of warming is poorly understood, the true cost of reduced world economic growth is very well understood and is very high.  The real question, then, is do we understand global warming and its potential downsides enough to believe that curbing them outweighs the almost certain negative impact from a poorer world.

I will begin by conceding some warming

Typically when making this argument, I will concede some man-made global warming.  It is hard to refute the fact from various CO2 concentration estimates that man has increased the amount of CO2 in the atmosphere over the last 50 years, and that this CO2 likely has had and will have some impact on global temperatures.  As a result, I am willing to concede a degree or two of warming from man-made effects over the next century.  This is lower than most of the warming estimates that you see in the press, but scientists will have to nail down a lot more issues before they can convince me these higher numbers are correct.  Some of these issues include:

• World temperatures rose by a half degree in the first half of the 20th century through mostly natural phenomena.  No one knows why (though solar activity may help explain it), but even global warming's strongest supporters agree that it was probably not due to man.  No one can therefore with any accuracy separate warming in the late 20th century due to this natural effect and warming due to man's impact.  Check out Mann's now-famous hockey stick below:

Global warming advocates love this chart - I mean this is their chart, not the skeptics' - and it probably plays well with non-scientific editors who are believers themselves, but I sure wouldn't want to defend this in a board room.  What if this were a sales chart, and I wanted to claim that the sales increase after I started work in 1950 was all due to my effort.  I can just see my old boss Chuck Knight at Emerson, or maybe Larry Bossidy at AlliedSignal, saying - "well Warren, it sure looks like things changed in 1900, not 1950.  And whatever was driving things up from 1900 to 1950, why do you think that that effect, which you can't explain, suddenly stopped and your influence took over.  And by the way, why did you end your chart with 1998 - I seem to remember 1998 was the peak.  Isn't it kind of disingenuous to leave off the last 6 years when the numbers came back down some?" (update:  Even in the arctic, where the media writes with so much confidence that global warming is having a measurable impact, the difference between cyclical variations and man-made effects is hard to unravel.)

• No one really understands the cyclical variations in world temperatures and climate.  I think it is large, and certainly there are historical records of the last 800 years that seem to point to climactic extremes.  Mann, et. al. claim to have shown that man's effects dwarf these natural variations with their 1000-year hockey stick, but there are a lot of problems with Mann, not the least of which is his unbelievably suspicious refusal to release his data and methodology to the scientific community, behavior that would not be tolerated of any other scientist except one who supported the global warming consensus view.
• It is still not clear that the urban heat island effect has been fixed in the ground data, so satellite data tends to show less warming (but some none-the-less).
• The climate models are absurd in ways even a non-climatologist can figure out.  For example, economies in energy inefficient undeveloped nations are assumed to grow like crazy in the IPCC scenarios, such that "then the average income of South Africans will have overtaken that of
  Americans by a very wide margin by the end of the century. 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."
• I no longer trust the scientific community on global warming.  This quote from National Center for Atmospheric Research (NOAA) researcher and global warming action promoter, Steven Schneidersays it all:

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.

While many serious scientists are working on the issue, 100% of the anti-growth, anti-technology, anti-America, and anti-man folks have jumped strongly on the global warming bandwagon, and many of these folks have in fact grabbed the reins, leading major efforts and groups.  It is important to note that these folks do not care about scientific accuracy or facts.  Their agenda is completely and absolutely to use global warming as their lead issue to push their anti-growth agenda.  As such, none of these folks are going to tolerate any fact, study, or scientific voice that in any way questions the global warming orthodoxy.  And can any scientist be considered serious who uttered the following statement (from the UN's IPCC Conference Summary, page 2):

"It is
likely that, in the Northern Hemisphere, ... 1998 [was] the warmest year during the past thousand years."

My physics instructors in college used to criticize us students constantly for not understanding the error range in our lab work.  I wonder what they would think of a group of scientists that stated with confidence that 1998 was the warmest year in the last one thousand, when they only have direct measurement for the last 100 years or so and even then over only a small percentage of the planet and the other 900 years are estimated from tree rings and ice cores.  I am tired of being criticized as a Luddite for challenging "scientists" who think they know with confidence the exact world temperature since Charlemagne. 

Anyway, to avoid getting bogged down in this mess, I am willing to posit some man-made warming, say 1-2 degrees over the next 100 years.  For most who argue the subject, this is the end of the discussion.  For me, it is just the beginning.

What impact, warming?

Beyond bad cinema and Sunday supplement hyperbole, its difficult to find the good science aimed at quantifying the impacts, positive and negative, from global warming.  In fact, it is impossible in any venue at any level of quality to find any mention of the positive impacts of warming, though anyone with half a brain can imagine any number of positive impacts (e.g. longer growing seasons in cold climates) that will at least partially offset warming negatives.

Now, I am sure many scientists would respond that climate is complicated, and its hard to judge what will happen.  Which I believe is true.  But surely the same scientists that can cay that the world will warm by x degrees with enough certainty to demand that billions or even trillions of dollars be spent to change energy use should be able to come to some conclusions about the net effects, both positive and negative, from warming.

Certainly sea levels will probably rise, as some ice caps melt, by maybe a foot in the consensus view.  And storms and hurricanes may get worse, though its hard to separate the warming effect from the natural cyclical variation in hurricane strength, at least in the Atlantic.  What does seem to be clear is that the warming disproportionately will occur in colder, drier climates.  For example, a large part of the world's warming will occur in Siberia. 

When I hear this, I immediately think longer growing seasons in cold climates plus less impact in already warm climates = more food worldwide.  It strikes me that since the climate models tend to spit out warming not only world wide but by area of the world, it would be fairly easy to translate this into an estimate of net impact on food production.  This seems to be such an obvious area of study that I can only assume it has been done, and, since we have not heard about it, that the answer from global warming was "increased food production".  Since this conclusion neither supports scary headlines, increased grant money, or the anti-growth agenda, no one really talks about it or studies it much.  I would bet that if I took all the studies and grants today aimed at quantifying the impact of global warming, more than 95% of the work, maybe 100% of the work, would be aimed solely at negative impacts, studiously ignoring any positive counter-veiling effects.

I often get looks from global warming advocates like I am from Mars when I suggest work needs to be done to figure out how bad warming is, or even if it is really that bad at all.  I have learned that there are typically two reasons for this reaction:

1. I am talking to one of the anti-growth types, for whom the global warming issue is but a means to the end of growth limitation.  These folks need global warming to be BAD as a fundamental premise, not as something that can be fact-checked.  They cannot have people questioning that global warming is the ultimate bad thing that trumps everything else anymore than the Catholic Church can have folks start to question the fallibility of the Pope.
2. I am talking to an environmentalists who considers man's impact impact on earth as bad, period.  It is almost an aesthetic point of view, that it is fundamentally upsetting to see man changing the earth in such a measurable way, irregardless of whether the change affects man negatively.  These are the same folks with whom you cannot argue about caribou in ANWR.  They don't oppose ANWR drilling because they honestly think the caribou will be hurt, but because they like the notion that there is a bunch of land somewhere that man is not touching

By the way, though I know this will really mark me as an environmental Luddite, does anyone really believe that in 100 years, if we've really screwed ourselves by making things too hot, that we couldn't find a drastic way to cool the place off?  Krakatoa's eruption put enough dust in the air to cool the world for a decade.  The world, unfortunately, has a lot of devices that go bang laying around that I bet we could employ to good effect if we needed to put some dust in the stratosphere to cool ourselves off.  Yeah, I am sure that there are hidden problems here but isn't it interesting that NO ONE in global warming, inc. ever discusses any option for solving warming except shutting down the world's economies?

What impact, Intervention?

While the Kyoto treaty was a massively-flawed document, with current technologies a Kyoto type cap and trade approach is about the only way we have available to slow or halt CO2 emissions.  And, unlike the impact of warming on the world, the impact of such a intervention is very well understood by the world's economists and seldom in fact disputed by global warming advocates.  Capping world CO2 production would by definition cap world economic growth at the rate of energy efficiency growth, a number at least two points below projected real economic growth.  In addition, investment would shift from microprocessors and consumer products and new drug research and even other types of pollution control to energy. The effects of two points or more lower economic growth over 50-100 years can be devastating:

• Currently, there are perhaps a billion people, mostly in Asia, poised to exit millenia of subsistence poverty and reach the middle class.  Global warming intervention will likely consign these folks to continued poverty.  Does anyone remember that old ethics problem, the one about having a button that every time you pushed it, you got a thousand dollars but someone in China died.  Global warming intervention strikes me as a similar issue - intellectuals in the west feel better about man being in harmony with the earth but a billion Asians get locked into poverty.
• Lower world economic growth will in turn considerably shorten the lives of billions of the world's poor
• A poorer world is more vulnerable to natural disasters
• The unprecedented progress the world is experiencing in slowing birth rates, due entirely to rising wealth, will likely be reversed.  A cooler world will not only be poorer, but likely more populous as well.  It will also be a hungrier world, particularly if a cooler world does indeed result in lower food production than a warmer world
• A transformation to a prosperous middle class in Asia will make the world a much safer and more stable place, particularly vs. a cooler world with a billion Asian poor people who know that their march to progress was halted by western meddling.
• A cooler world would ironically likely be an environmentally messier world.  While anti-growth folks blame all environmental messes on progress, the fact is that environmental impact is a sort of inverted parabola when plotted against growth.  Early industrial growth tends to pollute things up, but further growth and wealth provides the resources and technology to clean things up.  The US was a cleaner place in 1970 than in 1900, and a cleaner place today than in 1970.  Stopping or drastically slowing worldwide growth would lock much of the developing world, countries like Brazil and China and Indonesia, into the top end of the parabola.  Is Brazil, for example, more likely to burn up its rain forest if it is poor or rich?

The Commons Blog links to this study by Indur Goklany on just this topic:

If global warming is real and its effects will one day be as devastating as
some believe is likely, then greater economic growth would, by increasing
greenhouse gas (GHG) emissions, sooner or later lead to greater damages from
climate change. On the other hand, by increasing wealth, technological
development and human capital, economic growth would broadly increase human
well-being, and society's capacity to reduce climate change damages via
adaptation or mitigation. Hence, the conundrum: at what point in the future
would the benefits of a richer and more technologically advanced world be
canceled out by the costs of a warmer world?

Indur Goklany attempted to shed light on this conundrum in a recent paper
presented at the 25th Annual North American Conference of the US Association for
Energy Economics, in Denver (Sept. 21, 2005). His paper "” "Is a
richer-but-warmer world better than poorer-but-cooler worlds?" "” which can
be found here, draws
upon the results of a series of UK Government-sponsored studies which employed
the IPCC's emissions scenarios to project future climate change between 1990 and
2100 and its global impacts on various climate-sensitive determinants of human
and environmental well-being (such as malaria, hunger, water shortage, coastal
flooding, and habitat loss). The results indicate that notwithstanding climate
change, through much of this century, human well-being is likely to be highest
in the richest-but-warmest world and lower in poorer-but-cooler worlds. With
respect to environmental well-being, matters may be best under the former world
for some critical environmental indicators through 2085-2100, but not
necessarily for others.

This conclusion casts doubt on a key premise implicit in all calls to take
actions now that would go beyond "no-regret" policies in order to reduce GHG
emissions in the near term, namely, a richer-but-warmer world will, before too
long, necessarily be worse for the globe than a poorer-but-cooler world. But the
above analysis suggests this is unlikely to happen, at least until after the
2085-2100 period.

Policy Alternatives

Above, we looked at the effect of a cap and trade scheme, which would have about the same effect as some type of carbon tax.  This is the best possible approach, if an interventionist approach is taken.  Any other is worse.

The primary other alternative bandied about by scientists is some type of alternative energy Manhattan project.  This can only be a disaster.   Many scientists are technocratic fascists at heart, and are convinced that if only they could run the economy or some part of it, instead of relying on this messy bottom-up spontaneous order we call the marketplace, things, well, would be better.  The problem is that scientists, no matter how smart they are, miss with their bets because the economy, and thus the lowest cost approach to less CO2 production, is too complicated for anyone to understand or manage.  And even if the scientists stumbled on the right approaches, the political process would just screw the solution up.  Probably the number one alternative energy program in the US is ethanol subsidies, which are scientifically insane since ethanol actually increases rather than reduces fossil fuel consumption.  Political subsidies almost always lead to investments tailored just to capture the subsidy, that do little to solve the underlying problem.  In Arizona, we have thousands of cars with subsidized conversions to engines that burn multiple fuels but never burn anything but gasoline.  In California, there are hundreds of massive windmills that never turn, having already served their purpose to capture a subsidy.  In California, the state bent over backwards to encourage electric cars, but in fact a different technology, the hybrid, has taken off.

Besides, when has this government led technology revolution approach ever worked?  I would say twice - once for the Atomic bomb and the second time to get to the moon.  And what did either get us?  The first got us something I am not sure we even should want, with very little carryover into the civilian world.  The second got us a big scientific dead end, and probably set back our space efforts by getting us to the moon 30 years or so before we were really ready to do something about it or follow up the efforts.

If we must intervene to limit CO2, we should jack up the price of fossil fuels with taxes, or institute a cap and trade scheme which will result in about the same price increase, and the market through millions of individual efforts will find the lowest cost net way to reach whatever energy consumption level you want with the least possible cost.  (The only real current alternative that is rapidly deploy-able to reduce CO2 emissions anyway is nuclear power, which could be a solution but was killed by...the very people now wailing about global warming.)

Conclusion

I would like to see some real quality discussion as to the relative merits of the path the world is on today vs. an interventionist world that is cooler but poorer, more populous, hungrier, and less politically stable.  If anyone knows of some thoughtful work in this area, please leave a link in the comment area or in my email.

By the way, I got through this whole post without mentioning or quoting Bjorn Lomborg, which really is not fair since he has been very eloquent about just this cooler but poorer argument, but since he is treated like the anti-Christ by global warming believers, it generally only causes people to stop listening when you mention him.

Note finally that other past articles in this series can be found here and here and here.

Disclosure:   I am not funded in any way by the automobile or electric power industry. In fact, my personal business
actually benefits from higher oil prices, since our recreation sites
tend to be near-to-home alternatives for those who can't afford to
drive across country, so global warming intervention would probably help me in the near term.  However, I do own a fair amount of Exxon-Mobil stock, so you may assume that all my opinions are tainted, following the tried and true Global Warming formula that any money from the energy industry is automatically tainting, but incentives that tie grant money, recognition, or press exposure to the magnitude of warming a scientist predicts never carry a taint.  My opinions carry with them an honest concern for the well-being of non-Americans, like the Chinese, which I'm told used to be considered a liberal value until liberals and progressives decided more recently that they actually fear and oppose economic growth in places like China.

For quite a while, I have wanted to see that someone address the question of comparing a richer and warmer world with a poorer and cooler world, and not just assuming that the latter is superior.  As I wrote here, this is one of the most important questions ignored to date by Kyoto supporters.  Supporters of immediate climate change action shout warnings about the dangers of raising the earth's temperature a degree or two.  But what if that comes at the cost of reducing world economic growth a percentage or two?  There is still a lot of work to be done to understand the impacts of a 1-2 degree temperature rise, but it is very, very well understood what 1-2 extra points of economic growth can do, especially in developing countries.  Economic growth reduces starvation, increases life expectancy, improves health care and sanitation, and increases the ability to survive natural disasters.

The Commons Blog links to this study by Indur Goklany on just this topic.  I have not had time to get through it all -- I am just happy someone is even asking the question -- but the Commons Blog folks have:

If global warming is real and its effects will one day be as devastating as
some believe is likely, then greater economic growth would, by increasing
greenhouse gas (GHG) emissions, sooner or later lead to greater damages from
climate change. On the other hand, by increasing wealth, technological
development and human capital, economic growth would broadly increase human
well-being, and society's capacity to reduce climate change damages via
adaptation or mitigation. Hence, the conundrum: at what point in the future
would the benefits of a richer and more technologically advanced world be
canceled out by the costs of a warmer world?

Indur Goklany attempted to shed light on this conundrum in a recent paper
presented at the 25th Annual North American Conference of the US Association for
Energy Economics, in Denver (Sept. 21, 2005). His paper "” "Is a
richer-but-warmer world better than poorer-but-cooler worlds?" "” which can
be found here, draws
upon the results of a series of UK Government-sponsored studies which employed
the IPCC's emissions scenarios to project future climate change between 1990 and
2100 and its global impacts on various climate-sensitive determinants of human
and environmental well-being (such as malaria, hunger, water shortage, coastal
flooding, and habitat loss). The results indicate that notwithstanding climate
change, through much of this century, human well-being is likely to be highest
in the richest-but-warmest world and lower in poorer-but-cooler worlds. With
respect to environmental well-being, matters may be best under the former world
for some critical environmental indicators through 2085-2100, but not
necessarily for others.

This conclusion casts doubt on a key premise implicit in all calls to take
actions now that would go beyond "no-regret" policies in order to reduce GHG
emissions in the near term, namely, a richer-but-warmer world will, before too
long, necessarily be worse for the globe than a poorer-but-cooler world. But the
above analysis suggests this is unlikely to happen, at least until after the
2085-2100 period.

It is particularly important to do the economic work using the same assumptions that the climatologists use. As I posted before, climate studies tilt the playing field in the favor of warming by assuming huge economic growth rates in developing nations.  This ups CO2 emissions estimates, because it is also assumed that these countries remain inefficient energy consumers.  I have criticized this approach in the past, since it yields ridiculous outcomes (many of these smaller nations end up with economies larger than the US in 2050).  However, if they are going to insist on these assumptions, that should also be the backdrop for estimating economic impact of reductions. Presumably, since in their model CO2 comes disproportionately from developing country growth, then the costs will be seen disproportionately in terms of reduced developing country growth.  Which will have predictable results in terms of malnutrition, starvation, disease, and shorter lifespans.

Technorati Tags:  Environment, Economics

Advocates for radical government intervention to halt climate change claim that they have "proven" the case for limitations on CO2 emissions beyond the doubt of anyone except contemptible corporate greed-hounds.  As Todd Zwycki quotes Ellen Goodman:

The climate is equally apparent in the struggle over what the Bush
administration calls "climate change" "” and everyone else calls global warming.
The only way to justify doing nothing about global warming now is to
deliberately muddle the science. It's not an accident that Philip Cooney,
the White House official caught editing reports on greenhouse gases, left for
Exxon Mobil, which has indeed funded doubts.

I have written on the burden of proof that is needed to justify Kyoto-like interventions a number of times, most recently here.  This is what I think has been "proven" sufficiently well.

1. Proven: Man-made CO2 has increased the concentration of CO2 in the atmosphere (best evidence from ice cores and samplings in Hawaii)
2. Proven:  Temperatures in the world have risen since 1900. (though perhaps less than typicaly reported due to under-correction for urban heat-island effects).
3. Proven:  The temperature rise in the first half of the 1900's was not man-made, having occured before substantial man-made CO2 production, and therefore is attributable to some other (disputed and/or unknown) effect.

Here is what is still in doubt, with no consensus:

1. In Dispute:  How much of the world temperature rise since 1950 was due to man-made CO2 output?   Some unknown phenomena caused a pre-1950 rise, leaving open the question of how much this other phenomena raised temperatures in the latter half of the 1900's and how much was due to man-made CO2.
2. In Dispute:  How much will the world's temperature rise in the future due to man-made CO2?  Climate is a complex animal, and no honest thinking climate scientist believes they have the right model yet, particularly since none of the most-used models explains history very well.  Also, beyond climate, the economic models that drive CO2 levels in the climate model are hugely flawed, causing the models to way over-estimate man-made CO2 production.
3. In Dispute:  What are the positives and negatives of global warming for humans?  The negatives are dealt with all too casually, in the sort of unproven scare story day-after-tomorrow unscientific approach that makes good NY Times Sunday Edition reading but does little to introduce any facts.  The positives are never, ever mentioned. "Disinterested" climate scientists never mention that some parts of the world will benefit, in terms of longer growing seasons, or that most of the warming will occur in winter nights in the coldest regions, where warming would be welcome.  Its almost as if they weren't disinterested and had an interest in the answer coming out a certain way.

Wait, we are not done yet.  There is one critical questions that is never even addressed by global warming advocates:

1. Not Even Addressed:  How do the costs of limiting CO2 emissions, including decreased economic growth and increased poverty, stand up against the dangers?  No one has done a good study of this, though people like Bjorn Lomburg have argued that the cost-benefit is much worse than solving some of the world's other problems.

Basically, the philosophy of environmentalists is that if man changed the world, its worth any cost to reverse it.  Sorry, but this is not sufficient evidence to trash the world economy with new taxes and output restrictions. 

Todd Zwycki, in the article linked above, has a nice analysis:

So the real question to ask here is whether on net, the costs of doing
something about global climate change outweigh the benefits of doing it. This is
the same question we ask (or should ask) about every other intervention into
nature--should we kill the parasites in water so that we can drink it, should we
drain a mosquito-infested swamp to eliminate the risk of malaria, should we
provide a vaccine to kill naturally-occurring smallpox. To imply that if the
science shows we are changing the climate we must do something about it is as
wrongheaded as it would be to say that if we are not contributing to global
warming we should not do anything about it.

On the question of whether global warming would be a net benefit or detriment
to the planet, the evidence I have seen to date suggests that it is
inconclusive. There will be impacts on crop yields, growing locations, forests,
energy consumption, etc., that cut in many different directions. The question of
whether the warming will occur equally throughout the world, or whether it will
occur more strongly in the coldest parts of the world appears to also be
unsettled, and has powerful normative implications for policy. To get bogged
down in the science, and especially in causal questions, seems to me to be
largely beside the point.

Kyoto and similar protocols are dying, and for entirely predictable reasons.  Story in TCS from Buenos Aires.

The conventional wisdom that it's the United States against the rest of the world in climate change diplomacy has been turned on its head. Instead it turns out that it is the Europeans who are isolated. China, India, and most of the rest of the developing countries have joined forces with the United States to completely reject the idea of future binding GHG emission limits. At the conference here in Buenos Aires, Italy shocked its fellow European Union members when it called for an end to the Kyoto Protocol in 2012. These countries recognize that stringent emission limits would be huge barriers to their economic growth and future development.

None too soon for me.

If you have never checked out JunkScience.com, you should.  They do a nice job of providing balance and fact-based analysis for many science "stories" in the media, particularly those where the science is driven by political correctness or a litigation and/or political agenda.  The spend a lot of time on global warming, mainly because there is just so much bad science there to criticize, but they range all over, from the latest food Nazi threats to the latest chemical contamination panic.

Last week, they release their 10 most embarrassing moments of 2004.  One example:

10. University of Arkansas researchers attacked the Atkins Diet in January with a report linking a high-carbohydrate diet with weight loss, saying it was possible to lose weight without cutting calories and without exercising. What they didn't reveal, however, was that the study subjects who lost weight actually ate 400-600 calories per day less than those who didn't lose weight.

Never, ever, ever trust a science story in the press.  The press has no idea how to use or manipulate data (if they had been able to do math, they would not have been journalism majors in the first place).  The press generally publishes science stories by cribbing 95% of the story from activists press releases.  Even when there is data in the story, rather than just bald unsupported declarations, it is either seriously flawed, or more humorously, contradicts the text of the story.

I can't resist supporting this statement with a couple of examples from JunkScience.com.

This is a temperature chart for Central Park, NY.  It gets a lot of play in the press as a "common sense" proof of global warming, and comes right off the NASA climate site:

Now, lets ignore the fact that urbanization could be causing a local temperature increase that does not reflect a general climate trend.  Lets, however, select our time frame a little differently.  Lets take the whole data set, which goes back further, rather than this set chosen by activists to make their point.  The same data over a longer trend looks like this:

OOPS!  Gee, I am not sure Central Park looks much warmer.  In fact, you could argue it is cooler.  Hmmmm.  Ask yourself if you really think it was an accident that the year with the single lowest temperature in the middle of the second graph was used as the starting point for the first.

OK, one other, because I can't resist.  There is some debate (though perhaps not enough) about what temperature data set to use - ground level readings, satellite data, balloons, etc.  It might not stun you to learn that out of 3-5 alternative temperature data sets, global warming activists choose not the middle or the average but the single set (ground temperatures) that show by far the most warming to date.  By coincidence, this data set is perhaps the least reliable, since it never has had anything like 100% area coverage, it is subject to the most human error, and it is influenced by urban warming effects. 

However, if you want to use ground data, certainly the most reliable is data for the United States, where data has been taken over a larger coverage area for more time with more consistent standards than any other location.  Global Warming activists will love to show this chart of US temperatures since about 1978:

Wow, that looks bad - looks like a nearly one degree Celsius rise in less than 25 years.  This is the "hockey stick" climatologists refer to.  Let's leave aside that this same rise is not visible in satellite data or other measurement approaches.  Like the NYC data, lets take a longer time span.  Can you guess why this chart begins in 1978? 

So we are not even at the high's for the last 100 years - those occured in the 1930's  (you remember - drought, dust bowl, etc?)

OK, that's just a taste - check out their web site for more.  In addition, you can read my post on the Kyoto treaty to find other skeptics of global warming, as well as some specific information about how Kyoto is more an anti-American treaty than an environmental treaty.

UPDATE

Based on some responses I have gotten, its probably best that I point out that the reason for posting the charts above was not to "disprove" global warming.  It was to just make the point that you need to be careful with any science you see in the media.  If you look here or here, you will see where I am on global warming, which basically that manmade warming probably exists but is being overstated for a variety of reasons.  In fact, my whole point here is really that you CAN'T prove or disprove something as complex, chaotic, and poorly understood as climate change with 2 or 3 charts.