The Wall Street Journal contradicts itself on global warming
The Wall Street Journal is universally admired among journalists for its news and analysis; for its editorial page, not so much. A spectacular example of the latter’s ability to mislead appeared yesterday, under the cute title Not So Hot, in which the anonymous editorializers adroitly attacked NASA, environmentalists, climate change models, and climatologists James Hansen and Gavin Schmidt over a statistically insignificant data correction. The misleading editorial was rewarded with great popularity, as the piece was the second-most emailed of the day, right after a feature on beer pong.
But interestingly, two weeks ago the number-crunchers at the WSJ ran a feature analyzing the exact same controversy in the column called The Numbers Guy, prosaically entitled "Global Warming Debate Overheats with Bad Numbers." This gives Grist readers a unique opportunity to compare the WSJ news-and-analysis team versus the WSJ editorial team. Judge for yourself.
Canadian and amateur climate researcher Stephen McIntyre discovered that NASA made a technical error in standardizing the weather air temperature data post-2000. These temperature mistakes were only for the U.S.; their net effect was to lower the average temperature reading from 2000-2006 by 0.15C.
The new data undermine another frightful talking point from environmentalists, which is that six of the 10 hottest years on record have occurred since 1990. Wrong. NASA now says six of the 10 warmest years were in the 1930s and 1940s.
The Numbers Guy:
“NASA has now silently released corrected figures, and the changes are truly astounding,” wrote a blogger at dailytech.com. Even Rush Limbaugh devoted a chunk of his radio program to the issue, saying, “One of the central tenets of the global warming hoaxers today is that 1998 was the hottest year in history on record … It turns out that the statistics, the temperature data that NASA used to compile the temperatures in 1998 is wrong.”
But the commentators are mistaken. Part of the story is true: Mr. McIntyre, a former mining-industry executive who is well-known for efforts to scrutinize climate-change data, did find a calculation error in a NASA Web page listing the average U.S. temperatures over the last 127 years. NASA had been combining thermometer data from two different sources — one until 1999, and another source for afterward. But the two sources had been calibrated differently, and the agency hadn’t properly accounted for the difference. Mr. McIntyre pointed the error out to scientists at NASA, who posted a revised file last Tuesday. And the revised file did list 1934 as slightly warmer, in the continental U.S., than 1998 — by 1/50th of a degree Celsius — though it turns out the flaw discovered by Mr. McIntyre had nothing to do with that. More on this last point in a moment.
In an interview, Mr. McIntyre said he just wanted NASA to be more transparent about how it calculates the annual temperature averages. “The reaction in the right-wing blogosphere is overwrought,” Mr. McIntyre said. “I certainly haven’t said that this is some kind of magic bullet that disproves global warming.”
It’s also not clear that the 0.15 degree temperature revision is as trivial as NASA insists. Total U.S. warming since 1920 has been about 0.21 degrees Celsius. This means that a 0.15 error for recent years is more than two-thirds the observed temperature increase for the period of warming. NASA counters that most of the measured planetary warming in recent decades has occurred outside the U.S. and that the agency’s recent error would have a tiny impact (1/1000th of a degree) on global warming.
If nothing else, the snafu calls into question how much faith to put in climate change models. In the 1990s, virtually all climate models predicted warming from 2000-2010, but the new data confirm that so far there has been no warming trend in this decade for the U.S. Whoops.
The Numbers Guy:
Pegging the “warmest year” in the U.S. is difficult. Because there are fewer thermometers measuring temperatures in the U.S. than in the whole world, estimates of the average U.S. temperature are less precise than those for the globe. Reto A. Ruedy, a NASA scientist who helps calculate the data, said NASA’s measurements of average yearly temperature in the continental U.S. have a margin of error of 0.47 degree Celsius. As a result, at least 12 years out of the last 127 can claim to be in a statistical tie for warmest in the U.S. NASA’s correction concerned only U.S. temperatures, meaning it has little or no bearing on the “global” warming argument. Global warmest has been something of a moving target: The Intergovernmental Panel on Climate Change wrote in 2001 that 1998 was the warmest year on record, but that conclusion was made obsolete by 2002, 2003, 2004, 2005 and 2006 — all of which were also quite warm.
What’s more disturbing is what this incident tells us about the scientific double standard in the global warming debate. If this kind of error were made by climatologists who dare to challenge climate-change orthodoxy, the media and environmentalists would accuse them of manipulating data to distort scientific truth.
The Numbers Guy:
In an early 2007 update, 1998 had edged ahead, but by July, 1934 was back on top by 1/50th of a degree Celsius. All of these movements were the result of NASA’s calibrations, not the flaw identified by Mr. McIntyre. The latest shift showed up on NASA’s Web site when it did because the agency incorporated all of its latest data online when it was making the unscheduled update to address the flaw Mr. McIntyre spotted.
Mr. McIntyre said he doesn’t contest the notion that the flaw he identified had nothing to do with the change in ranking for 1934 and 1998. He has exchanged e-mail with Mr. Ruedy about the flaw, but not on that issue. (The two have a less-than-cordial relationship after another dust-up earlier this year.) In the view of NASA’s Mr. Ruedy, the fact that 1934 and 1998 were well within the margin of error before (and still are) makes it silly to try to rank them. “This is totally ridiculous,” Mr. Ruedy said. “Lots of noise about noise.”
Translation: Agreement between experts on revision of complicated facts: not exciting. NASA admits error on global warming! Very exciting.
Just forget about the "statistically insignificant" part.