Updated data from NASA satellite instruments reveal the Earth’s polar ice caps have not receded at all since the satellite instruments began measuring the ice caps in 1979. Since the end of 2012, moreover, total polar ice extent has largely remained above the post-1979 average. The updated data contradict one of the most frequently asserted global warming claims – that global warming is causing the polar ice caps to recede.
The timing of the 1979 NASA satellite instrument launch could not have been better for global warming alarmists. The late 1970s marked the end of a 30-year cooling trend. As a result, the polar ice caps were quite likely more extensive than they had been since at least the 1920s. Nevertheless, this abnormally extensive 1979 polar ice extent would appear to be the “normal” baseline when comparing post-1979 polar ice extent.
Updated NASA satellite data show the polar ice caps remained at approximately their 1979 extent until the middle of the last decade. Beginning in 2005, however, polar ice modestly receded for several years. By 2012, polar sea ice had receded by approximately 10 percent from 1979 measurements. (Total polar ice area – factoring in both sea and land ice – had receded by much less than 10 percent, but alarmists focused on the sea ice loss as “proof” of a global warming crisis.)