Earliest Greenland Melting on record by far Several times in the past few years, North America has r
Earliest Greenland Melting on record by farSeveral times in the past few years, North America has received blasts of cold air that typically would have headed north over Greenland. A pattern of low-pressure systems to the west and high pressure over the North Atlantic keeps developing, and in the process cold air is pushed south and warm air is drawn to the north.The latest round of this weather pattern just shattered historic records for how the Greenland ice sheet behaves. Typically, as the sun reaches the northern hemisphere in the summer, Greenland begins melting, with the earliest ever melting period arriving in May. The melting season is defined as the point when 10% of the Ice Cap has melted enough to produce 1 cm of water and prior to this year the earliest onset of this melting stage was on May 5, 2010.This year, Greenland has already started melting, breaking the previous record by nearly a month. The combination of warm weather in the arctic during the winter and another extreme warm air event triggered large-scale melting on Greenland’s southeast coast in early April. The event was so out of the ordinary that the scientists who monitor the ice cap admit they double-checked to make sure their equipment was working correctly. Sites high up on the Greenland Ice Sheet were recording temperatures typically seen in July, not during April. Temperature forecasts suggest that parts of the ice sheet will approach 30°C above their normal average before this specific system passes.Greenland’s ice sheet is facing many stresses, including long-term temperature changes, darkening of the ice due to pollution that leads to more melting, and the loss of grounded ice on the glaciers that drain the ice caps. Even when those effects are combined with the strong 2015-2016 El Niño, it’s still startling to see that the Greenland Melt season has the ability to jump so early in the year, to a time when the ice cap is just getting its first rays of sunlight.-JBBImage credit: Polar Portalhttp://bit.ly/1T2nGOYReferences:http://bit.ly/1N7gVfEhttp://bit.ly/22sILog -- source link
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