(On December 31, 2009, NASA finally provided the Competitive Enterprise Institute with the documents I requested from them with an FOIA in August 2007. My request asked NASA to release their internal discussions regarding a series of errors in their claims of warming U.S. temperatures caught by Steve McIntyre. NASA had stonewalled my request for more than two years.)

A principal theme of these NASA emails — and one that is illuminating in its exposition of advocacy and hypocrisy at NASA’s Goddard Institute for Space Studies (GISS) — is the insistence that what turned out to be a false warming of 0.15 degrees in the U.S. record is meaningless, even if covering merely seven years (2000-2006, as opposed to a decadal or longer trend).

In an August 7, 2007, email from GISS’ Dr. Reto Ruedy to GISS director Dr. James Hansen, Ruedy says the correction had “little impact” on the U.S. record. In an email to New York Times environmental reporter Andrew Revkin on August 9, 2007, Hansen characterizes the error as having been “well within the uncertainty bar we give” for the U.S. and “entirely negligible” globally. In an email to Dr. Donald E. Anderson — program manager, Earth Science Enterprise, NASA Headquarters — on August 14, 2007, Hansen used the terms “minor,” “negligible,” and “less than the uncertainty” to describe the previously touted warming which was now shown to be an error.

This did not explain why the warming merited all of the hype in the preceding seven years.

Further, a week later Hansen privately wrote to Revkin that “[we] can add an uncertainty” to actually do what Hansen had been spinning to Revkin that they already do:

Indeed we already include a bar at several points on our temperature curve, but we note that it only includes the largest source of uncertainty in the temperature change (incomplete spatial coverage).

To add some further, curious texture to Hansen’s remarkably flexible view of what magnitude of warming is meaningful, note how in an August 14, 2007, email to GISS’ Makiko Sato and Ruedy, Hansen describes a claimed, much smaller warming between 1934 over 1998 of 0.02 degrees Celsius — which Hansen’s own 2001 paper had shown to be 0.5 degrees Celsius, a full half degree — as being “slightly warmer.” It is fair to assume from the record of NASA GISS that, because 1934 is an older year, the disparity must be downplayed. But it is also rather troubling that Hansen had forgotten his own work, serially rejecting the notion that he ever said 1934 was warmer than 1998, and his newer, operative claim that the difference is actually only 0.02 degrees Celsius, “much less than the accuracy” of their instruments. Therefore, he says: “Of course, scientifically, this is all nonsense.”

There is indeed nonsense in the various double standards that the emails reveal about NASA GISS, over how much and what kind of anomalies (warm or cool) are meaningful. Though not as he suggests.