The Melting of the Cryosphere and Implications for the Planet

摘要

As global temperatures increase, ice sheets and glaciers are rapidly melting. Sea levels continue to rise forcing the relocation of low-lying populations and threatening water supplies for millions of people. On the west coast of Greenland, the average temperature in winter has risen 5℃ in the past two decades. In the Arctic, sea ice is on the decline with the ice pack getting thinner and thawing further from shore. The current rate of sea ice loss during the summer is about 10 percent per decade. At the current rate of melting, the Arctic Ocean could be completely ice free by the end of the 21 st century. The average temperature of the West Antarctic Peninsula has increased by more than 2℃ since the 1950s and the midwinter temperatures have warmed by as much as 5℃ during the same time period. The second largest iceberg ever measured broke free from the Ross Ice Shelf in March 2000, and in 2002, the Larsen Ice Shelf lost 1200 square miles of ice. Warmer temperatures are causing glaciers in the Himalayas and the Tibetan Plateau to melt faster during the summer, causing major flooding in the lowlands while the lack of snowfall at higher elevations during the warmer winters is causing drought. The same is true of the glaciers along the equator in Africa including Mt. Kilimanjaro. The glaciers in the European Alps have decreased by 50 percent since the 1900s and are predicted to disappear by the middle of the 21st century. And, Glacier National Park has lost 80 percent of its glacial ice since 1850 and is expected to be ice free within 30 years, which could cause the name of the park to be changed. This research examines the current state of the cryosphere and the negative impacts associated with melting glaciers.