Example of Climate Work That Needs to be Checked and Replicated
When someone starts to shout "but its in the peer-reviewed literature" as an argument-ender to me, I usually respond that peer review is not the finish line, meaning that the science of some particular point is settled. It is merely the starting point, where now a proposition is in the public domain and can be checked and verified and replicated and criticized and potentially disproved or modified.
The CRU scandal should, in my mind, be taken exactly the same way. Unlike what more fire-breathing skeptics have been saying, this is not the final nail in the coffin of catastrophic man-made global warming theory. It is merely a starting point, a chance to finally move government funded data and computer code into the public domain where it has always belonged, and start tearing it down or confirming it.
To this end, I would like to share a post from year ago, showing the kind of contortions that skeptics have been going through for years to demonstrate that there appear to be problems in key data models -- contortions and questions that could have been answered in hours rather than years if the climate scientists hadn't been so afraid of scrutiny and kept their inner workings secret. This post is from July, 2007. It is not one of my most core complaints with global warming alarmists, as I think the Earth has indeed warmed over the last 150 years, though perhaps by less than the current metrics say. But I think some folks are confused why simple averages of global temperatures can be subject to hijinx. The answer is that the averages are not simple:
A few posts back, I showed how nearly 85% of the reported warming in the US over the last century is actually due to adjustments and added fudge-factors by scientists rather than actual measured higher temperatures. I want to discuss some further analysis Steve McIntyre has done on these adjustments, but first I want to offer a brief analogy.
Let's say you had two compasses to help you find north, but the compasses are reading incorrectly. After some investigation, you find that one of the compasses is located next to a strong magnet, which you have good reason to believe is strongly biasing that compass's readings. In response, would you
- Average the results of the two compasses and use this mean to guide you, or
- Ignore the output of the poorly sited compass and rely solely on the other unbiased compass?
Most of us would quite rationally choose #2. However, Steve McIntyre shows us a situation involving two temperature stations in the USHCN network in which government researchers apparently have gone with solution #1. Here is the situation:
He compares the USHCN station at the Grand Canyon (which appears to be a good rural setting) with the Tucson USHCN station I documented here, located in a parking lot in the center of a rapidly growing million person city. Unsurprisingly, the Tucson data shows lots of warming and the Grand Canyon data shows none. So how might you correct Tucson and the Grand Canyon data, assuming they should be seeing about the same amount of warming? Would you
average them, effectively adjusting the two temperature readings
towards each other, or would you assume the Grand Canyon data is cleaner
with fewer biases and adjust Tucson only? Is there anyone who would not choose the second option, as with the compasses?
The GISS data set, created by the Goddard Center of NASA, takes the USHCN data set and somehow uses nearby stations to correct for anomalous stations. I say somehow, because, incredibly, these government scientists, whose research is funded by taxpayers and is being used to make major policy decisions, refuse to release their algorithms or methodology details publicly. They keep it all secret! Their adjustments are a big black box that none of us are allowed to look into (and remember, these adjustments account for the vast majority of reported warming in the last century).
We can, however, reverse engineer some of these adjustments, and McIntyre does. What he finds is that the GISS appears to be averaging the good and bad compass, rather than throwing out or adjusting only the biased reading. You can see this below. First, here are the USHCN data for these two stations with only the Time of Observation adjustment made (more on what these adjustments are in this article).
As I said above, no real surprise "“ little warming out in undeveloped nature, lots of warming in a large and rapidly growing modern city. Now, here is the same data after the GISS has adjusted it:
You can see that Tucson has been adjusted down a degree or two, but Grand Canyon has been adjusted up a degree or two (with the earlier mid-century spike adjusted down). OK, so it makes sense that Tucson has been adjusted down, though there is a very good argument to be made that it should be been adjusted down more, say by at least 3 degrees**. But why does the Grand Canyon need to be adjusted up by about a degree and a half? What is biasing it colder by 1.5 degrees, which is a lot? The answer: Nothing. The explanation: Obviously, the GISS is doing some sort of averaging, which is bringing the Grand Canyon and Tucson from each end closer to a mean.
This is clearly wrong, like averaging the two compasses. You don't average a measurement known to be of good quality with one known to be biased. The Grand Canyon should be held about the same, and Tucson adjusted down even more toward it, or else thrown out. Lets look at two cases. In one, we will use the GISS approach to combine these two stations"“ this adds 1.5 degrees to GC and subtracts 1.5 degrees from Tucson. In the second, we will take an approach that applies all the adjustment to just the biases (Tucson station) "†this would add 0 degrees to GC and subtract 3 degrees from Tucson. The first approach, used by the GISS, results in a mean warming in these two stations that is 1.5 degrees higher than the more logical second approach. No wonder the GISS produces the highest historical global warming estimates of any source! Steve McIntyre has much more.
** I got to three degrees by applying all of the adjustments for GC and Tucson to Tucson. Here is another way to get to about this amount. We know from studies that urban heat islands can add 8-10 degrees to nighttime urban temperatures over surrounding undeveloped land. Assuming no daytime effect, which is conservative, we might conclude that 8-10 degrees at night adds about 3 degrees to the entire 24-hour average.
Postscript: Steve McIntyre comments (bold added):
These adjustments are supposed to adjust for station moves "“ the procedure is described in Karl and Williams 1988 [check], but, like so many climate recipes, is a complicated statistical procedure that is not based on statistical procedures known off the island. (That's not to say that the procedures are necessarily wrong, just that the properties of the procedure are not known to statistical civilization.) When I see this particular outcome of the Karl methodology, my mpression is that, net of the pea moving under the thimble, the Grand Canyon values are being blended up and the Tucson values are being blended down. So that while the methodology purports to adjust for station moves, I'm not convinced that the methodology can successfully estimate ex post the impact of numerous station moves and my guess is that it ends up constructing a kind of blended average.
LOL. McIntyre, by the way, is the same gentleman who helped call foul on the Mann hockey stick for bad statistical procedure.
tomw:
For some reason, I have been suspicious about every single one of the 'corrections' and 'adjustments' applied to the raw data. It is easy to presume a conscious or even unconscious bias is built into the thought process used in designing the corrections.
December 5, 2009, 10:33 amBut the real point is, why are they doing it at all? What does .X or .0X of a degree on Tuesday actually mean, especially after it has been massaged?
The GAT [global average temp] could be observed at a very small number of sites, chosen because of the minimal influence of external variables, where good historical data was available. If these sites showed an increase, it would stand out over and above the normal 'noise' that one observes. If there is a trend, it would show up. To measure the daily temperature out by Uncle Franks chicken coop means nothing. Too many things have changed in too many places, and it really is trying to model the world. What sense does that make? It cannot be done[yet, anyway].
Think about what they are doing. Getting thousands of measurements, mucking about with them, averaging them, using fudge factors to fill in the missing data gaps, to the point where the mass of data held has no relation to the world. It doesn't mean anything except that the average of their 'cooked, smoked and tortured data' is what they want it to be. When you consider they are measuring and correcting in tenths of a degree for the type and style of buckets used to measure the surface sea temperature, they have gone beyond reality. They are trying to measure with a micrometer, mark with a dull pencil, and cut with a chain saw. The number [ONE ONLY] they get from all this mastication of data is meaningless.
Get some real temperature data, with history, with minimal angle of incidence and heat island effect and use that. I recommend Malaysia or Indonesia.
tom
Link:
There's another bias, isn't there? Most of the US is more like the Grand Canyon (rural) than Tucson (urban). How does any kind of simple averaging of the two adjust for this? You'd have similar issues melding land temperatures with temperatures over our oceans.
Incredibly the folks who say that they know how to determine the "average current temperature of "Earth" -- not an easy thing to do actually -- won't tell us how they do it. You have to question almost any scientific conclusion being drawn, because the data being used has been compromised in so many ways.
I've been an AGW skeptic, not because of the science but because the politics is so bad. Neither the Energy bill, nor anything that may come from Copenhagen, will fix the AGW problem if we have an AGW problem. I've worked backwards from there on the science.
"Divergence" would have told me that the assumption that tree rings could be a proxy for historic global temperatures -- with precision -- was suspect. Instead, Mann & Co used a trick to hide the decline. Later they came up with a non-tree ring proxy set that magically conformed to their original. I smell a pack of rats here.
December 5, 2009, 10:50 amLink:
tomw made several of my points, but better. I didn't see his post while I was off writing mine.
If there's an issue with determining current GAT [global average temp], why do we think we can do it with precision for the last 1,000 years. We don't have a time machine to calibrate use of proxies -- in fact the proxies failed to calibrate with post 1960 data.
The key point is "precision." I learned in my first high school science class that you can't make your conclusion more accurate than the data you work with. It's one thing to use proxies like tree rings to survey historic climate conditions. It's another to say that global average temperature was 55.2 degrees in 1605 for purposes of a trend line to run computer forecasts of the future.
If this was the only time Mann & Co were suspect over their use of data, it'd be one thing. But they're known serial data molesters. We've given Mann and his cronies the only set of keys to the main data bank. That's like putting known pederasts in charge of an orphanage. How many times does Steve McIntyre have to call them out?
December 5, 2009, 11:03 amTom Karl:
I am not sure what you are implying here. We are doing our best, using peer review and finely honed intuitive imaginations. Who are the experts here? You? No, it's us! You are nobody, so don't question what we do.
My recommendation? Go to climate school. Study under Michael Mann or James Hansen. If you survive such a selective training process, perhaps you can be a peer reviewed author yourself, and be taken seriously.
Until then, please stick to what you know.
We're the government: we're here to help you.
December 5, 2009, 12:18 pmmahtso:
The absurdity of the AGW debate is seen in Mr. Karl's comment: Is he serious or is it satire? I don't know because, to me, it does represent the position of many of the alarmists.
December 5, 2009, 12:47 pmjoshv:
I'll go you one further - what the hell is an average temperature? You will never find a physicist using such a quantity, as it's meaningless. Temperatures are not additive, thus they are not average-able - think about it: 50 degF + 70 degF = 120 degF then divide by two to get the average of 60 degF. The first step is meaningless.
The result is not a temperature - it's just a numerical average of two temperatures, with no other physical meaning. Now one might try to take this derived number and correlate it to real data at a specific location, perhaps crop yields, growing days, temperature at a given location, sea level, etc... But the number in itself has no meaning. It's increase does *not* mean the Earth is getting hotter. It means a particular idiosyncratic statistical average of temperatures has increased - nothing more.
December 5, 2009, 1:10 pmLink:
I see the point on averaging temperatures.
But I'm inclined to agree with tomw -- You could put measuring stations at key locations to measure trends. If you did so, you could develop meaningful analysis for geographical regions. You'd still have to be patient and track data for meaningful lengths of time, probably over decades at a minimum. It's still useful to know how hot and dry the Midwest is now compared to say the 1930s.
The conceit is pretending that you can extend this approach to determine GAT. You still have significant issues over what you're actually measuring, because as joshv points out -- it's really not an average. But even if you got the sample size right, and worked out locations to do this -- so as to have a proxy for GAT, you'd have to be very patient in collecting data to do any meaningful analysis. You'd need hundreds of years of real time data, for openers.
Mann & Co appear to have made a projection back in time using proxies, despite these constraints, so they don't have to wait on 1,000 years of data to do their studies. They then project their projection yet again in computer simulations.
It also seems to me that the better scientific approach is to look at this from perspective of millions of years of Ice Age cycles -- anything we think we're measuring could just be a statistical blip within the context of known cycling.
December 5, 2009, 1:50 pmEscapedWestOfTheBigMuddy:
The unconscience bias issue has been shown to apply to many fields, and some (like particle physics, my field) have taken to "blinding" the raw data whenevery possible. Blinding often takes the form of a simple additive or multiplicative offset not known to the analysis team applied to the raw data.
Note, however, that this kind of deal doesn't always come for free, so it is not a trivial choice.
December 5, 2009, 2:26 pmme:
The sad corollary to this entire debate is that the majority of people do not understand what "the scientific method" (never mind "science") means.
It doesn't matter that some guy said something. It doesn't matter if they are important or just a guy off the street. It doesn't matter if a theory sounds nice. It doesn't matter if a non-scientist gets it demonstrably right or if a scientist is a lying data-falsifying scum bag.
Science is not about loyalty or who turned out to be right in the end, it's about demonstrating causal relationship. It's about measurable, provable truth.
If you can create a theory that allows for predictions of a system state in the future for both positive as well as negative outcomes and you can demonstrate that your predictions based on that theory are always true and if you can describe your method and theory in such a manner that other people can reproduce your results, you're doing science. Everything else is just a bunch of monkey magic.
The problem with the climate debate is that because of the timescales involved and the fact that we only have one earth to play with, there is no way to do do actual experiments in the sense above.
Even more, because there's only one Earth and it's subject to participating in this process no matter what, the climate debate lends itself to the "think of the children" argument - you can justify any action, no matter how harsh, based on a perceived high risk to something unique and dear.
December 5, 2009, 3:03 pmDr. T:
The temperature data issue is worse than stated. Seventy-five percent of our planet is covered by oceans and large lakes, yet only a small percentage of temperature readings in the climate models are made above these waters. And, those readings aren't evenly distributed across the planet's waters, but tend to lie close to heavily populated land masses. When climatologists make claims about mean global temperatures, they are full of crap.
December 5, 2009, 4:37 pmmorganovich:
another item worth considering is that even the average temperature from a rural station is not really average temperature.
the stations take a max and a min reading for the day, average them, and call it temperature. it's easy to conceive of many ways in which such a reading could diverge from the minute by minute average.
further, such a max + min/2 approach greatly increases the effects of poor siting. surfacestations.org is full of pictures of thermometers next to burn barrels, or near ventilation equipment. virtually all of the US "rural" stations are actually at airports. one plane idling nearby could drive a 5 minute temperature spike that then becomes HALF the figure for the day.
the UHI noise in the system exceeds the signal (per century) being measured by at least 3X and quite possibly more like 6X.
no other disciple would call what emerges from the terrestrial temperature network (even before it is adjusted) useful data.
December 5, 2009, 6:17 pmboballab:
Here is something to ask yourself. They say they have tempature records that go back X amount of years so they know what the temp is. Ok then think of this are you using the same thermometer the entire time since oh say 1900? All Thermometers are not created equal. Depending on how the thing is made, what its made out of and how old the thing is all play in a Thermometers accuracy. So think about it can they really claim that a Thermometer that was used from 1900 to 1930 when it got busted was accurate to such a small degree over the entire length of its life? Heck no, since they can't calibrate it to anything modern. That Thermometer could have been 2 degrees off for all they knew. Now just multiply that error factor into each thermometer that is used, over the entire history of reading s and basically all you got is a SWAG on what the global average mean temp is for 1900, 1910 and so forth with a wider margin of error then they want to admit.
December 5, 2009, 6:55 pmDKN:
The problem we are seeing with CRU et al. is not limited to CRU et al. I worked one summer at a major federal lab doing hydroclimatology modeling. This involved linking a soil-vegetation-atmosphere-transfer model(SVAT)to the RAMS regional climate model. Critically, the SVAT calculated all the hi-rez surface flux of sensible(SH)and latent heat(LH)and passed that to RAMS. For input they wanted to use 10m resolution digital soil and veg maps. Well, SH and LH are quite sensitive to soil and vegetation characteristics and their spatial distribution, but there were no such things as regional soil and veg maps at 10m rez. So they just processed the 1Km scale maps to get them, quite probably introducing spatial and magnitude bias in the resulting flux calcs, but refused to test for bias as this was "too expensive and time consuming". I could not sign off on that and quit the project.
December 5, 2009, 8:11 pmperlhaqr:
[T]he folks who say that they know how to determine the “average current temperature of “Earth†— not an easy thing to do actually — won’t tell us how they do it.
"Can I see your data?"
"No."
Well, can I at least see your methodology?"
"No, not that either."
"Well, how can I tell you're doing it right?"
"Well, my friend Bob looked at it, and he says it's all good. You should just trust me. Also, the check is in the mail, and I won't come in your mouth."
December 5, 2009, 11:57 pmNikFromNYC:
If you can, please explain what *this* alarming version of the Grand Canyon data is?:
http://data.giss.nasa.gov/cgi-bin/gistemp/gistemp_station.py?id=425723760080&data_set=1&num_neighbors=1
The version you have above seems to be this one?:
http://data.giss.nasa.gov/cgi-bin/gistemp/gistemp_station.py?id=425723760080&data_set=2&num_neighbors=1
December 6, 2009, 2:53 amLink:
The UN IPCC just said, "full speed ahead." Gordon Brown just called skeptics like me "flat Earthers." The PM doth protest too much.
In contrast, the BBC has a decent and fair summary here:
http://news.bbc.co.uk/2/hi/science/nature/8376286.stm
They've got open comments here:
http://newsforums.bbc.co.uk/nol/thread.jspa?forumID=7310&edition=2&ttl=20091206165551
This is more than we're seeing from US MSM, who appear to have snuffed Climategate. I expect this story to die out largely, barring some other major development.
Understand that anything that comes out of Copenhagen won't affect the course of AGW, even if it is happening. The events there will be comical.
December 6, 2009, 10:12 amO Bloody Hell:
This is more than we’re seeing from US MSM, who appear to have snuffed Climategate. I expect this story to die out largely, barring some other major development.
Don't let it.
Exhausting the enemy is a standard libtard technique. You cannot allow them to win by default.
December 6, 2009, 10:29 pmLink:
I thought further on this,
Here's a subtle but I think important fallout of MSM coverage of AGW: There's over 20 million Rush listeners -- truck drivers etc etc -- who now know a lot about Siberian tree rings. But Katie Couric doesn't want to know from Siberian tree rings. The ombudsman at the New York Times just gave it a pass on not knowing from Siberian tree rings. But Katie and the NYT will say Sarah Palin is a no-nothing. Don't you understand what you're breeding here politically? ps. my Dad was a truck driver.
These Rush listeners now know more about Siberian tree rings than most college faculty members. That's a profound disconnect.
Watch what happens when Obama returns from Copenhagen expecting a triumph for cutting a "deal" that kills US jobs over bent science. He may be heralded in some quarters -- and MSM -- but the rest of America will be seething. Many of these folks slid over to Obama in 2008 over disgust with Bush -- my Dad likely would have -- but you can't tell where they'll go in 2010 and 2012. If you really piss off these kinds of people be ready for peasants at your doorstep with firebrands and pitchforks.
December 6, 2009, 10:48 pmDoug:
Now we're finally getting to a question that I asked in another comments section (not to say I'm some sort of genius). I've long maintained that if you gave a data set of any sort to 1,000 different scientists, or engineers, or statisticians, and wanted to extract some info from it ("average temp," for instance), you'd get 1,000 different answers. How can there EVER be any agreement on anything if there's no agreement on the analysis technique? I do electrical engineering. We have well-defined units of measurement (volts, amps, watts, etc.). There is no such thing in climate science, which is why it is the farce that it is.
December 6, 2009, 11:14 pm