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Greenland - Climate

A complete melting of the Greenland ice cap would cause the water level of all the world's oceans to rise 20 feet. Usually, the melting season extends from June to August, with the majority of dissipation occurring in July. However, the 2019 dry, rising temperatures contributed to thinner ice sheets along the country’s western edge. The icy surface works as a mirror, typically reflecting the sun’s glare, a phenomenon known as the albedo effect. However, this year’s low snowpack left the ice sheet unprotected and weaker than usual. Due to a lower winter accumulation than normal, the bare ice area has been exposed very early in this area enhancing the melt due to the melt-albedo feedback. Therefore, at the beginning of the melt season, the snowpack along the west coast is now preconditioned to break records of melt.

Greenland lost over two billion tons of ice after a major melt, scientists at the University of Georgia said, calling the event ”unusual, but not unprecedented.” Research scientist Thomas Mote, an expert in Greenland’s climate said, "We've seen a sequence of these large melt seasons, starting in 2007, that would have been unprecedented earlier in the record … we didn't see anything like this prior to the late 1990's."

Greenland experienced unprecedented temperature spikes in 2016, causing the country's huge ice sheet to melt. Scientists warn that if it melted entirely, global sea level would rise by at least seven meters. Climate change explains a lot. Everything is changing rapidly. Now, it freezes over later in the year and the ice melts earlier. Winter is growing shorter. Locals can no longer go to certain islands by sled because the ice isn’t solid or thick enough. It doesn’t extend far enough either.

Residents are so used to doing everything on ice that they find it hard to adapt. But the fear that climate change will destroy the culture of indigenous peoples is really more of a concern of educated people who don’t actually live in the Arctic.

Greenland, the world's largest island, is almost entirely covered by a massive ice sheet that is roughly the size of Mexico (700,000 square miles), is up to two miles thick, and contains nearly a tenth of the world's fresh water supply. If this ice sheet were to melt completely, sea levels would rise by over 20 feet. Even a 3-foot increase in sea levels would threaten some 70 million people living in coastal zones around the world.

The rapid changes seen in Greenland over the last decade suggest we are dangerously close to a climatic tipping point. During a visit to Dr. Konrad Steffen's research station on the Greenland ice sheet, Select Committee members learned about the mounting scientific evidence which makes clear that global warming is causing an alarming acceleration in the rate of melting of the Greenland ice sheet. Average temperatures in southern Greenland have increased by over 4 degrees Fahrenheit in the past two decades, and the area of Greenland's ice sheet that melts each summer has increased by 16 percent from 1979 to 2002. During the record-setting melting in 2005, satellites recorded melting in areas that have never melted in the past 27 years.

This surface melting further threatens the ice sheet by causing lakes to form on the ice sheet's surface. The meltwater then percolates downwards through massive cracks in the ice sheet called "moulins," lubricating the base of the ice sheet and hastening the slide of glaciers towards the sea. As a result, several of Greenland's largest glaciers are now flowing towards the sea at nearly 8 miles per year, twice as fast as they did just 5 years ago.

The Greenland ice sheet now dumps nearly three times as much ice into the sea as it did 10 years ago-enough every 2 to 3 days during the melting season to supply New York City with fresh water for an entire year. The amount of ice flowing into the sea from Greenland's ice cap now appears to be outpacing the buildup of snow further inland. Scientists have also observed an alarming increase in "ice quakes" due to glacial movement-measuring up to 5.0 on the Richter scale-raising questions about the ice sheet's stability. These trends indicate that the accelerating melting of Greenland's ice sheet increases the risk of dangerous sea-level rise sooner than previously predicted.

On a local scale, global warming is already having negative impacts on the livelihoods of Greenland's indigenous Inuit population of roughly 45,000. The loss of stable, year-round sea ice is disrupting traditional seal-hunting and fishing practices on which Inuit livelihoods depend. And, as elsewhere in the Arctic, melting of permafrost is causing extensive damage to homes and other infrastructure in Inuit villages. During the Select Committee's trip to Greenland, the Greenland Premier Hans Enoksen, national and local leaders, and residents all emphasized that changes to their environment are rapid and far reaching economic and cultural impacts.

By 2050, the end-of-summer Arctic ice volume can be expected to be down by about 40%, of which about 15% would be due to decreased extent and the remaining 25% would be seen in an end-of-summer thickness reduced by 25% to about 1.5 m. What does this mean in terms of various regions of the Arctic? During winter, the central Arctic and all peripheral seas including the Greenland Sea, Bering Sea, and Gulf of St. Lawrence will continue to have significant ice cover. Extent and, in most areas, ice thickness will be reduced. The Sea of Okhotsk and Sea of Japan will be ice-free for the entire year. In late summer, the entire Russian coast will be ice-free, allowing navigation through the Barents, Kara, Laptev and East Siberian Seas along the entire Northern Sea Route. The Northwest Passage through the Canadian Archipelago and along the coast of Alaska will be ice-free and navigable every summer by non-icebreaking ships. Ice will be present all year along the eastern and northern coasts of Greenland. Ice will also remain throughout the summer within and adjacent to the northern Canadian Archipelago. Significant ice will remain in the central Arctic Ocean, though the mean thickness will be about 1.5 m, and it will be less compact.






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Page last modified: 19-08-2019 16:16:22 ZULU