Arctic amplification may be driving the loss of ice in Greenland, a 2015 study concludes. This effect could alter climate around the globe.
Ice loss on Greenland is likely driving the loss of frozen cover around the rest of the Arctic. This results in a faster rate of warming in the highest latitudes compared with the rest of the northern hemisphere, a phenomenon known as Arctic amplification. As ice disappears, larger areas of ocean appear dark, absorbing additional thermal radiation from the sun, resulting in a feedback loop, driving faster warming in the Arctic.
During the summer of 2015, the loss of ice cover on Greenland drove the jet stream over the land mass further north than at any point in recent history for that time of year. Winds that normally blow from west to east switched direction, blowing over Greenland from east to west.
"Last year was unique in the extensive melting that occurred on the northern reaches of the ice sheet, an area that usually has rather modest melt compared to southern Greenland. We identified an unusual configuration of the jet stream toward northern Greenland that led to this melt pattern," Thomas Mote of the University of Georgia said.
Greenland possesses the second-largest ice sheet in the world, behind only Antarctica. If all of this ice were to melt, sea levels around the world would rise an average of 23 feet.
Although Arctic amplification has been well-documented over the course of decades, the effects of the phenomenon on the atmosphere has been debated. One theory holds that a reduction in temperature differences between Arctic and temperate areas could slow down the jet stream. Such an effect would result in greater quantities of warm, humid air traveling into northern latitudes.
Increased melting rates of ice over Greenland may not have been the result of Arctic amplification, but researchers believe evidence points in this direction. Further study will have to measure whether this pattern continues over time, which would lend further evidence to the conclusions of the new study.
Investigation of how Arctic amplification may be driving the loss of ice in extreme northern latitudes could assist investigators in predicting how anthropogenic warming could affect global warming. As ice melts off the island nation, fresh water delivered into the oceans can radically alter circulation patterns in the water.
Examination of the loss of ice sheets in Greenland, and analysis of how Arctic amplification could be affecting the climate, was published in the journal Nature Communications.