Most people who are savvy about climate change are also aware that if and when massive segments of Greenland collapse and melt, it will be all over for coastal cities. Places like New York, Miami, and others will have to build enormous and monstrously expensive dykes if they are to survive at all. Thus the latest news about Greenland, as reported in the article 'Record Summer Melt in Greenland in 201' ((Eos Transactions of the American Geophysical Unions) is not encouraging at all.
According to the article, a recent analysis of surface glaciological observations, remote sensing satellite data and refined model outputs shows new records for surface melt, albedo, runoff and the number of days when bare ice was exposed. Increased melting, as we know, acelerates albedo which is defined as the proportion of solar radiation reflected back into space. As we know, the darker the surface, i.e. the less reflecting ice, the more solar radiation is absorbed to warm the Earth under the CO2 greenhouse blanket. Bottom line: we always want as much covering ice as possible near the polar caps, never less, and never mind the idiots clamoring for an "Arctic passage" to ease travel!
The article in Eos goes on to note that large areas of the ablation zone in Greenland underwent melting for over 50 days longer than the 1979-2009 average of 48 melting days per year. This may well have been because "warm conditions persisted through spring and summer, with the positive albedo feedback mechanism playing a major role in further enhancing melting and in leading to large, negative surface mass balance anomalies"
The notion of positive albedo feedback has already been well articulated, for example by the late Carl Sagan and others: Melting of ice caps (already occurring) results in diminished albedo (reflection of solar radiation back into space), and a darker Earth surface - with more infrared radiation absorbed - reinforcing the tendency while enhancing the melting effect, leading to further darkening of the surface, reduced albedo and more melting.
Aggravating the conditions, as noted in the report, the summer snowfall was below average while the melting during August and September was "exceptional". The article further noted that this melting and ablation was "consistent with near surface temperature anomalies of up to +3 Celsius." In other words, the surface temperatures seen that caused the effect were 3 degress Celsius above normal. Since each Celsius degree = 1.8 F, that means the surface temperatures were 5.4F above normal!
Obviously, a close monitoring of Greenland will have to continue through this spring and summer and we can only hope the melting isn't worse than it was last year. We must also hope that the austerity-deficit crazed Repukes don't slice any more from an already struggling science budget. It is in our interests not to do this!
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