Sunday, August 28, 2016

The Greenland Icesheet melt is significant and continuing. This year proved to have three important spikes in the melt.

2012 is a record year of melting in Greenland. It is the measure to the degree things are worse or not for the Greenland Ice Sheet, hence, sea level rise.
From 2012:
Nearly the entire ice sheet covering Greenland (click here) —from its thin coastal edges to its two-mile-thick center—experienced some degree of melting for several days in July 2012. According to measurements from three satellites and an analysis by NASA and university scientists, an estimated 97 percent of the top layer of the ice sheet had thawed at some point in mid-July, the largest extent of surface melting observed in three decades of satellite observations....
Climate data has to be assessed to understand this extensive melting. Also the ice remaining after the melt influences climate and the end of the melting. At any rate, without being boring, the ice melt in Greenland 2012 was a record setting melt of which a warming planet's effect on future melting may occur.
The latest assessment:
...According (click here) to an NSIDC blog post, the ice sheet saw three extreme spikes in melt by June 19. As a result, the pace of melting so far is ahead of the past three seasons, but behind the record melt year of 2012.
Coastal areas have been generally warmer than average, and sometimes extreme. For instance, temperatures in Nuuk soared to 24 degrees Celsius (75 degrees Fahrenheit) on June 9, 2016—the highest June temperature ever recorded there. Interior areas were slightly cooler than usual.
On June 15, 2016, the Advanced Land Imager (ALI) on NASA’s Earth Observing-1 satellite acquired a natural-color image of an area just inland from the coast of southwestern Greenland (120 kilometers southeast of Ilulisat and 500 kilometers north-northeast of Nuuk). According to Marco Tedesco, a professor at Columbia University’s Lamont Doherty Earth Observatory, melting in this area began relatively early in April but was not sustained. It started up again in May and grew into the watery June scene pictured above.
Surface melt can directly contribute to sea level rise via runoff. It can also force its way through crevasses to the base of a glacier, temporarily speeding up ice flow and indirectly contributing to sea level rise. Also, ponding of meltwater can “darken” the ice sheet’s surface and lead to further melting....