Science Ain't Beanbag—Antarctic Warming Edition
Last month Nature published an important paper claiming that researchers using a new statistical technique to process satellite and ground data had uncovered a 50 year warming trend over the southern continent. Earlier data had suggested that most of Antarctica was cooling rather than warming. This new finding was widely reported because it finally confirmed the predictions of computer climate models.
However, the climate blogosphere has erupted into a controversy over some of the data. It seems that one temperature trend was based on data from a ground station called "Harry ASW." To make a long story short, statistician Steve McIntyre who runs the skeptical website ClimateAudit apparently noticed an odd discontinuity in the Harry data--a very sudden jump in temperature. On further checking, it turns out that the British Antarctic Survey (BAS) had somehow combined data from another station called Gill with data from Harry which had been buried for years beneath the snow, producing an illusory jump in temperature. While McIntrye noted this problem on his blog, NASA scientist Gavin Schmidt who frequently blogs at RealClimate apparently reported the problem to the BAS.
So far, so good. Everyone wants to use good data. But what's roiling the climate blogosphere is who should get credit for uncovering the mistake? I don't know who's right or wrong in this case, so I'll just direct readers to various blogs where this is being hashed out.
First, University of Colorado environmental scientist Roger Pielke Jr.'s Prometheus blog has this take:
Due to an inadvertent release of information, NASA's Gavin Schmidt (a "real scientist" of the Real Climate blog) admits to stealing a scientific idea from his arch-nemesis, Steve McIntyre (not a "real scientist" of the Climate Audit blog) and then representing it as his own idea, and getting credit for it. (Details here and here.)
Later, Prometheus reports that Gavin Schmidt as written to Pielke's bosses demanding that he remove his blog post and issue an apology. There is an interesting discussion among commenters there about attributing scientific credit.
Meanwhile the lead researcher in the Nature report concludes the correction makes no real difference in the overall warming trend his team discovered. Over at Realclimate, Schmidt has a longer disquisition on what the corrections to the data mean (though he decorously passes over the attribution controversy):
Although science proceeds by making use of the work that others have done before, it is not based on the assumption that everything that went before is correct. It is precisely because that there is always the possibility of errors that so much is based on 'balance of evidence' arguments' that are mutually reinforcing…
The differences in the mean trends for Antarctica, or WAIS are very small (around 0.01ºC/decade), and the resulting new reconstruction is actually in slightly better agreement with the satellite-based reconstruction than before (which is pleasing of course).
Finally, the folks over at the Fabius Maximus blog have a pretty useful timeline and set of links explaining the controversy. FM concludes:
Scientists eventually will sort all these questions out. True believers (on both sides), who accept only science that confirms their views, will remain unaffected no matter what the result. It's called confirmation bias.
Yes indeed. Science ain't beanbag. With the internet, the sausage making of scientific discovery becomes ever more public. And that's a good thing.
