Saturday, February 21, 2009

Sensor Drift, A New Weapon In The Green Scare Or Just Henny Penny Coming Home To Roost

Why is it that every time there is a malfunction of some kind in environmental science methods, the error is always on the side of global warming? I'm just saying, from the hockey stick graph to forgetting the role of the sun in the Earth's climate, a conspiracy-minded individual might start to get suspicious.

The problem is that it's not the environmental scientists that are catching the's everyday folks looking at the data. OK, by folks I mean science geeks who work in windowless rooms and can looks at thousands of fields of data without getting drunk first.

Case in point. The National Snow and Ice Data Center was forced to admit that the maps they have been making this year of Arctic sea ice were grossly underestimating actual sea ice. The problem, something called sensor drift. The really big problem. A 5-year old could draw the edge of the sea ice better than the NSIDC.

A statement from the NSIDC clears things up:

As some of our readers have already noticed, there was a significant problem with the daily sea ice data images on February 16. The problem arose from a malfunction of the satellite sensor we use for our daily sea ice products. Upon further investigation, we discovered that starting around early January, an error known as sensor drift caused a slowly growing underestimation of Arctic sea ice extent. The underestimation reached approximately 500,000 square kilometers (193,000 square miles) by mid-February. 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. See below for more details.

We have removed the most recent data and are investigating alternative data sources that will provide correct results. It is not clear when we will have data back online, but we are working to resolve the issue as quickly as possible.

So by quality control, you guys at the NSIDC mean the random chance that a reader catches your mistakes.

The money quote from NSIDC:

On February 16, 2009, as emails came in from puzzled readers, it became clear that there was a significant problem: sea-ice-covered regions were showing up as open ocean...Sensor drift is a perfect but unfortunate example of the problems encountered in near-real-time analysis.

In other words, real-time data is great when it is used to gin up end-of-the-earth stories in the New York Times, but real time data "is what is is" when it makes you look like Henny Penny.

Obviously environmental scientists just don't get the BIG PICTURE. Credibility is king for researchers. Eventually, eventually the truth wins out. Real science will win out. And if you are not willing to participate in the actual scientific process, someone else (probably with a lot less grant money and fewer Hollywood friends) will expose your research for what it is. And when that happens, sensor drift (and all of the other excuses) will be exposed for what it is.

Researcher bias.

And by Henny Penny, I mean Henny Penny. Check out Prof Mark Serreze, a sea ice specialist at the National Snow and Ice Data Centre (NSIDC) and his "death spiral" - global warming hyperbole.

No comments:

Post a Comment