Tuesday, June 28, 2005

New Spencer and Christy data.

May 2005 update on the S&C satellite data

And in particular:

Global temperature trend since Nov. 16, 1978: +0.12 C per decade.

UAH is reprocessing the complete global temperature dataset to include a new correction, according to Dr. John Christy, director of the Earth System Science Center (ESSC) at The University of Alabama in Huntsville.

"The April and May 2005 results include that new correction," Christy said. "We expect to have the complete dataset available in time for the June Global Temperature Report."

It was previously 0.09C/decade - actually 0.086C/decade, generally rounded down to 0.08 by sceptics :-)

So the response to this should be amusing...


Steve Bloom said...

Doesn't this change amount to a complete retrenchment, or to put it more neutrally does it eliminate the controversy? Most importantly, will Spencer now be banned from Tech Central Station? :)

James Annan said...

Well, it won't make any difference to the debate over what, if anything, we should do - the sceptics may hang their hats on a different hook but that is the most we can expect to see in that regard.

From the scientific POV, I'm no expert in this area but I guess it will reduce what must have been considered a significant puzzle, to the level of a modest discrepancy.

Anonymous said...

This was the difference between the sat based measurements and the land based ones?

Sorry to ask an obvious question, but what was the gap before and what is it now?


James Annan said...

Land-based warming is about 0.15-0.17C/decade over the last 30 years. There are various analyses of satellite data (see wikipedia page) with S+C being the lowest, and the others ranging up to 0.2C/decade or more. Prior to 1998 the S+C data had no positive trend at all. It had recently crept up to 0.09C/decade, and now at 0.12C/decade it is still the lowest of the satellite analyses but looks more like confirmation than contradiction of the model results to me.