Branch Gorevidians lie again

Isn't it awfully convenient that the Branch Gorvidians are always quick to put out some proclamation like "Arctic Ice the size of Mars is missing on the polar cap". But then there's always a follow up that gets little to no press.

A glitch in satellite sensors caused scientists to underestimate the extent of Arctic sea ice by 500,000 square kilometers (193,000 square miles), a California- size area, the U.S. National Snow and Ice Data Center said.

The error, due to a problem called “sensor drift,” began in early January and caused a slowly growing underestimation of sea ice extent until mid-February. That’s when “puzzled readers” alerted the NSIDC about data showing ice-covered areas as stretches of open ocean, the Boulder, Colorado-based group said on its Web site.

“Sensor drift, although infrequent, does occasionally occur and it is one of the things that we account for during quality- control measures prior to archiving the data,” the center said. “Although we believe that data prior to early January are reliable, we will conduct a full quality check.’’

The extent of Arctic sea ice is seen as a key measure of how rising temperatures are affecting the Earth. The cap retreated in 2007 to its lowest extent ever and last year posted its second- lowest annual minimum at the end of the yearly melt season. The recent error doesn’t change findings that Arctic ice is retreating, the NSIDC said.

The center said real-time data on sea ice is always less reliable than archived numbers because full checks haven’t yet been carried out. Historical data is checked across other sources, it said.

Riiiight. But did you ever know the errors are never the other way around.

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