Errors and sensor drift
Losing 193,000 Miles of Ice
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The National Snow and Ice Data Center has admitted to losing 193,000 square miles of Arctic ice.
This misplaced ice is a result of “sensory drift” of satellite data. The NSIDC uses military satellites “by applying algorithms to data from a series of Special Sensor Microwave/Imager (SSM/I) sensors on Defense Meteorological Satellite Program (DMSP) satellites” to obtain their images, but these satellites were never designed for purely scientific purposes, and have given faulty data.
The NSIDC, is ” is part of the Cooperative Institute for Research in Environmental Sciences at the University of Colorado at Boulder” according to their website and is supported in part by NASA, home of the infamous James Hansen. While the NSIDC is far from partisan, they seem to have staked their reputation on the notion that sea ice-particularly in the Arctic-is doomed to disappear, a result of Anthropogenic Global Warming.
Why did NSIDC make this error? Because in their quality control phase they simply refused to believe that there was more ice than they expected? They explain;
“As discussed above, near-real-time products do not undergo the same level of quality control as the final archived products, which are used in scientific research published in peer-reviewed journals. However, the SSM/I sensors have proven themselves to be generally quite stable. Thus, it is reasonable to use the near-real-time products for displaying evolving ice conditions, with the caveat that errors may nevertheless occur. Sometimes errors are dramatic and obvious. Other errors, such as the recent sensor drift, may be subtler and not immediately apparent. We caution users of the near-real-time products that any conclusions from such data must be preliminary. We believe that the potential problems are outweighed by the scientific value of providing timely assessments of current Arctic sea ice conditions, as long as they are presented with appropriate caveats, which we try to do.
For several years, we used the SSM/I sensor on the DMSP F13 satellite. Last year, F13 started showing large amounts of missing data. The sensor was almost 13 years old, and no longer provided complete daily data to allow us to track total daily sea ice extent. As a result, we switched to the DMSP F15 sensor for our near-real-time analysis. For more information on the switch, see “Note on satellite update and intercalibration,” in our June 3, 2008 post.
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. The problem stemmed from a failure of the sea ice algorithm caused by degradation of one of the DMSP F15 sensor channels. Upon further investigation, we found that data quality had begun to degrade over the month preceding the catastrophic failure. As a result, our processes underestimated total sea ice extent for the affected period. Based on comparisons with sea ice extent derived from the NASA Earth Observing System Advanced Microwave Scanning Radiometer (EOS AMSR-E) sensor, this underestimation grew from a negligible amount in early January to about 500,000 square kilometers (193,000 square miles) by mid-February (Figure 2). While dramatic, the underestimated values were not outside of expected variability until Monday, February 16. Although we believe that data prior to early January are reliable, we will conduct a full quality check in the coming days.”
So, why doesn`t NSIDC use the more modern sensors of the NASA Earth Observing System Advanced Microwave Scanning Radiometer EOS AMSR-E? They were unwilling to disagree with the paradigm that Arctic ice is going to disappear:
“Sensor drift is a perfect but unfortunate example of the problems encountered in near-real-time analysis. We stress, however, that this error in no way changes the scientific conclusions about the long-term decline of Arctic sea ice, which is based on the consistent, quality-controlled data archive discussed above”
Now, I`m not accusing NSIDC of lying, or purposeful distortion of the truth (that`s a job for James Hansen) but I am saying that there is a default position held by many “establishment” types to choose the more “alarmist” position when there is a doubt-and that has a major impact on future projections. If we cannot get real time satellite data right, how can we get reliable projections of a future Armageddon? Even with direct measurements, there is a sizable fudge factor-in this instance a 193,000 mile of cold fudge (make mine maple, please!)
This is an unfortunate reflection of the problems with the entire Anthropogenic Global Warming scare; often faulty data is being fed into computer models, models that require a huge number of assumptions to make them work. These models have been tested by Patrick J. Michaels, S. Fred Singer, and David H. Douglass and found wanting, because they failed to predict current conditions based on historical data. The predictions made by these models have not been forthcoming, and model makers are still trying to find the lost heat in the oceans and in the tropical troposphere.
This mistake-one that the NSIDC has taken ownership of and corrected as quickly as possible-does not reflect poorly on this particular body so much as on the fundamental limitations of our observational abilities. How can we predict doom if we can lose a fifth of a million miles of ice, even while looking directly at it through a camera?
According to a carpenter I`ve known;
“Take therefore no thought for the morrow: for the morrow shall take thought for the things of itself. Sufficient unto the day is the evil thereof.”
We have wars, terrorists, rogue nations with nuclear weapons, penicillin-resistant diseases, chemical weapons, biological weapons which may include plague and even smallpox, we have the specter of total economic collapse through a spending spree of a trillion bucks, etc. Do we really need to worry about a computer game played by some over-funded geeks?
Sufficient unto the day, my friends! We have more immediate fish to fry.