“NASA Data Worse Than Climate-Gate Data, GISS Admits“. The latest scientific analysis Anthony Watts has copied-and-pasted is… a Fox News article! This is really scraping the bottom of the barrel.

Blake Snow of FOXNews.com reports as an admission of inferiority a NASA scientist’s assessment of the strengths and weaknesses of the different global surface temperature analyses. He also presents as definitive the opinion of Christopher Horner, a ‘senior fellow’ from the right-wing Competitive Enterprise Institute, that “three out of the four temperature data sets stink”. When another ‘senior fellow’ this time at the right-wing Heartland Institute, James M. Taylor, is quoted next and the article ends with our own Anthony’s unchallenged arm-waving about the “quality” of surface stations, you know the fix is in. “Fair & Balanced”, eh?

The only hint of reality comes from Dr. Jeff Masters at Weather Underground: “It would be nice if we had more global stations to enable the groups to do independent estimates using completely different raw data, but we don’t have that luxury”.

The real story? Climatologists have a limited number of long-duration surface temperature stations available to them. They use as many of those stations as possible. It’s a fundamental logical fact that they will all start with the same raw data. The differences will be in how they select representative stations from the entire data set and how they extrapolate from those stations.

As a final thought, I have to draw attention to the use of “accuracy” as the sole valid assessment of a temperature data set. Data can be accurate (very close to a true reading) but not as useful (doesn’t reflect the actual conditions over a wider area). The fundamental difference between the interpreted surface temperature data sets is that some are optimized for accuracy, some for global representativeness. There are good reasons for each approach. There are also good reasons why denialists try to define the argument on such narrow and misleading points.