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 ‚Äì 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 ‚Äì factoring in both sea and land ice ‚Äì had receded by much less than 10 percent, but alarmists focused on the sea ice loss as “proof” of a global warming crisis.)
A 10-percent decline in polar sea ice is not very remarkable, especially considering the 1979 baseline was abnormally high anyway. Regardless, global warming activists and a compliant news media frequently and vociferously claimed the modest polar ice cap retreat was a sign of impending catastrophe. Al Gore even predicted the Arctic ice cap could completely disappear by 2014.
In late 2012, however, polar ice dramatically rebounded and quickly surpassed the post-1979 average. Ever since, the polar ice caps have been at a greater average extent than the post-1979 mean.
Now, in May 2015, the updated NASA data show polar sea ice is approximately 5 percent above the post-1979 average.
During the modest decline in 2005 through 2012, the media presented a daily barrage of melting ice cap stories. Since the ice caps rebounded ‚Äì and then some ‚Äì how have the media reported the issue?
The frequency of polar ice cap stories may have abated, but the tone and content has not changed at all. Here are some of the titles of news items I pulled yesterday from the front two pages of a Google News search for “polar ice caps”:
The only Google News items even hinting that the polar ice caps may not have melted so much (indeed not at all) came from overtly conservative websites. The “mainstream” media is alternating between maintaining radio silence on the extended run of above-average polar ice and falsely asserting the polar ice caps are receding at an alarming rate.
To be sure, receding polar ice caps are an expected result of the modest global warming we can expect in the years ahead. In and of themselves, receding polar ice caps have little if any negative impact on human health and welfare, and likely a positive benefit by opening up previously ice-entombed land to human, animal, and plant life. Nevertheless, polar ice cap extent will likely be a measuring stick for how much the planet is or is not warming.
The Earth has warmed modestly since the Little Ice Age ended a little over 100 years ago, and the Earth will likely continue to warm modestly as a result of natural and human factors. As a result, at some point in time, NASA satellite instruments should begin to report a modest retreat of polar ice caps. The modest retreat ‚Äì like that which happened briefly from 2005 through 2012 ‚Äì would not be proof or evidence of a global warming crisis. Such a retreat would merely illustrate that global temperatures are continuing their gradual recovery from the Little Ice Age. Such a recovery ‚Äì despite alarmist claims to the contrary ‚Äì would not be uniformly or even on balance detrimental to human health and welfare. Instead, an avalanche of scientific evidence indicates recently warming temperatures have significantly improved human health and welfare, just as warming temperatures have always done.