Sunday, August 12, 2007


From Coyote Blog:

This is really big news, and a fabulous example of why two-way scientific discourse is still valuable, in the same week that both Newsweek and Al Gore tried to make the case that climate skeptics were counter-productive and evil.

Climate scientist Michael Mann (famous for the hockey stick chart) once made the statement that the 1990's were the warmest decade in a millennia and that "there is a 95 to 99% certainty that 1998 was the hottest year in the last one thousand years." (By the way, Mann now denies he ever made this claim, though you can watch him say these exact words in the CBC documentary Global Warming: Doomsday Called Off).

Well, it turns out, according to the NASA GISS database, that 1998 was not even the hottest year of the last century. This is because many temperatures from recent decades that appeared to show substantial warming have been revised downwards. Here is how that happened (if you want to skip the story, make sure to look at the numbers at the bottom).

One of the most cited and used historical surface temperature databases is that of NASA/Goddard's GISS. This is not some weird skeptics site. It is considered one of the premier world temperature data bases, and it is maintained by anthropogenic global warming true believers. It has consistently shown more warming than any other data base, and is thus a favorite source for folks like Al Gore. These GISS readings in the US rely mainly on the US Historical Climate Network (USHCN) which is a network of about 1000 weather stations taking temperatures, a number of which have been in place for over 100 years.

Frequent readers will know that I have been a participant in an effort led by Anthony Watts at to photo-document these temperature stations as an aid to scientists in evaluating the measurement quality of each station. The effort has been eye-opening, as it has uncovered many very poor instrument sitings that would bias temperature measurements upwards, as I found in Tucson and Watts has documented numerous times on his blog.

One photo on Watt's blog got people talking - a station in MN with a huge jump in temperature about the same time some air conditioning units were installed nearby. Others disagreed, and argued that such a jump could not be from the air conditioners, since a lot of the jump happened with winter temperatures when the AC was dormant. Steve McIntyre, the Canadian statistician who helped to expose massive holes in Michael Mann's hockey stick methodology, looked into it. After some poking around, he began to suspect that the GISS data base had a year 2000 bug in one of their data adjustments.

One of the interesting aspects of these temperature data bases is that they do not just use the raw temperature measurements from each station. Both the NOAA (which maintains the USHCN stations) and the GISS apply many layers of adjustments, which I discussed here. One of the purposes of Watt's project is to help educate climate scientists that many of the adjustments they make to the data back in the office does not necessarily represent the true condition of the temperature stations. In particular, GISS adjustments imply instrument sitings are in more natural settings than they were in say 1905, an outrageous assumption on its face that is totally in conflict to the condition of the stations in Watt's data base. Basically, surface temperature measurements have a low signal to noise ratio, and climate scientists have been overly casual about how they try to tease out the signal.

Anyway, McIntyre suspected that one of these adjustments had a bug, and had had this bug for years. Unfortunately, it was hard to prove. Why? Well, that highlights one of the great travesties of climate science. Government scientists using taxpayer money to develop the GISS temperature data base at taxpayer expense refuse to publicly release their temperature adjustment algorithms or software (In much the same way Michael Mann refused to release the details for scrutiny of his methodology behind the hockey stick). Using the data, though, McIntyre made a compelling case that the GISS data base had systematic discontinuities that bore all the hallmarks of a software bug.

Today, the GISS admitted that McIntyre was correct, and has started to republish its data with the bug fixed. And the numbers are changing a lot. Before today, GISS would have said 1998 was the hottest year on record (Mann, remember, said with up to 99% certainty it was the hottest year in 1000 years) and that 2006 was the second hottest. Well, no more. Here are the new rankings for the 10 hottest years in the US, starting with #1:

1934, 1998, 1921, 2006, 1931, 1999, 1953, 1990, 1938, 1939

Three of the top 10 are in the last decade. Four of the top ten are in the 1930's, before either the IPCC or the GISS really think man had any discernible impact on temperatures. [. . .]

So how is this possible? How can the global warming numbers used in critical policy decisions and scientific models be so wrong with so basic of an error? And how can this error have gone undetected for the better part of a decade? The answer to the latter question is because the global warming and climate community resist scrutiny. This weeks Newsweek article and statements by Al Gore are basically aimed at suppressing any scientific criticism or challenge to global warming research. That is why NASA can keep its temperature algorithms secret, with no outside complaint, something that would cause howls of protest in any other area of scientific inquiry.

Global warming supporting scientists will not release their raw data or their algorithms for two reasons. One is that they do not wish to help their competition. By competition I mean the other scientists who are chasing the same global warming grant money that they are. A researcher who has found a good global warming "angle" can rake in tens or millions of dollars in grant money from government agencies who are eager to purchase justifications for expanding government power over the economy. Global warming snake-oil salesmen don't publish information which could be co-opted by other "scientists" for the same reason that restaurants don't publish their recipes.

The other reason that you don't see researchers publish that kind of data is that they know in their hearts that it is flawed and that a rigorous examination would cause the entire global warming house of cards to come tumbling down. This causes them to hide the truth about individual items of "proof" of global warming and about the entire structure of global warming theory. A example of this kind of behavior in the scientific community can be seen in the Piltdown Man hoax.

In that affair the British Museum would not allow their fossils of the Piltdown Man "missing link" to be examined by outside scientists until after other fossils of a more credible human ancestor were discovered. Thus rendered superfluous in the battle to "prove" Darwin's theory of evolution they were opened to examination and quickly proven to be a hoax.

The data which supports the theory of human-caused global warming which will lead to catastrophic climate change is flawed and in some cases possibly falsified. There is a sense in the part of the scientific community which deals with climate and weather that this is true. However there is simply too much money and too much prestige associated with doing research which appears to verify global warming.

There is also an enormous incentive for journalists who specialize in reporting on global warming to support the myth. The news corporations are, for the most part, run by people who are very left-wing and support the same expansion of government power which drives the government's support of global warming alarmism and over half of the "environmental journalists" only have jobs because of the interest in global warming. Take that issue away and they would have to start looking for real jobs.

Just as the British Museum would not allow Piltdown Man to be examined by objective researchers until after a substitute missing link had been discovered and vetted the government, scientific establishment (which is now almost completely dependant on government handouts) and the media will not allow the global warming to be dispelled until another hobgoblin with equal power to terrorize the population and justify equal amounts of government expansion can be produced.