Lesson Learned at NASA

Apparently NASA's Goddard Institute for Space Studies (NASA GISS) learned its lesson in checking data quality before publishing their monthly GISS temperatures. GISS goofed last month when it published some erroneous data for the November global temperature. The data point, if true, would have meant the Earth experienced its hottest November since record keeping began. Why this didn't ring any alarm bells at Goddard before they "went live" with the data is still unclear, but once the error was found, NASA quickly updated the database with the corrected temperature (or more precisely, the change in temperature over a baseline averaged over the period 1951-1980). You can find their most recent data here.

As of this posting, NASA has NOT posted data for December 2008 nor have they released their formal assessment of the past year. The reason can be found here, with the relevant passage being

Starting this month, the data will be held, investigated, and potential problems reported to and resolved with the data provider before making them public. However, as we noted in the "Data Quality Control" section of our 1999 paper: We would welcome feedback from users on any specific data in this record.

Given how politically charged each data point is (something I believe they failed to recognize earlier), I think this is a wise move. There's no hurry. Get it right first.

BTW, although they didn't publish a formal assessment of 2008 temperatures, they do have a preliminary assessment. They note that this past year has been the coolest since 2000, but still ranks as the 9th warmest year since instrument records were first kept. Global Warming deniers will give you half of this information. Care to guess which half?