根据一项新的研究，在过去的30年里，南极洲失去的冰足以覆盖洛杉矶市10倍以上的面积。
冰川学家在加州大学欧文分校使用过去三十年的卫星图像来测量南极大陆冰盖的消退。
尽管超过四分之三的南极洲被发现是稳定的，但在过去的30年里，该大陆的其余部分经历了快速融化，根据发表在美国国家科学院学报.
冰川融化最快的地区是南极洲西部、南极洲半岛和南极洲东部的部分地区。研究人员说，自1996年以来，近5000平方英里的地面冰已经消失。
这项研究包括接地线的全面测绘-冰盖从基岩上分离并开始漂浮在海洋上的边界这是记录冰盖稳定性的“黄金标准”，加州大学欧文分校地球系统科学教授、论文的主要作者埃里克·里格诺特在声明中说。里格诺特说，这是首次在如此长的时间跨度内绘制出南极洲的接地线。
南极洲77%的海岸线没有基线迁移。然而，在最脆弱的地区，冰盖一直在以每年170多平方英里的速度从接地线后退。
最剧烈的变化发生在南极洲西部的阿蒙森海和盖兹地区，那里的冰川退缩了25英里。松树岛冰川后退了20多英里，思韦茨冰川后退了16多英里，史密斯冰川后退了26英里。
里格诺特说:“温暖的海水被风推向冰川，这就是我们在南极洲看到的大伤口。”
冰川学家对南极洲西部大陆架特别感兴趣，因为它有可能导致海平面的严重上升。斯韦茨冰川，也被称为“末日冰川”，已经占了全球冰川的4%总体海平面上升，而松树岛冰川是南极洲的融化最快的冰川.
如果西方南极洲冰盖将会完全崩溃，它有可能导致海平面上升9英尺研究人员称。
研究人员说，冰盖下温水的入侵解释了南极洲西部的大多数退缩模式，但位于南极洲东北部的南极半岛沿线的显著接地线迁移并不清楚。里格诺特说，在那个地区没有温水的证据。
“有别的东西在起作用——这仍然是个问号，”里格诺特说。
研究人员说，每三年，南极洲的脆弱地区就会失去相当于洛杉矶的地面冰。
“另一方面，我们也许应该感到幸运的是，整个南极洲现在都没有做出反应，因为我们会有更多的麻烦，”里格诺特说。“但这可能是下一步。”
Antarctica has lost ice 10 times the size of Los Angeles over the last 30 years, scientists say
Antarctica has lost enough ice over the last 30 years to cover the City of Los Angeles area 10 times over, according to new research.
Glaciologists at theUniversity of California, Irvine, used satellite images from the last three decades to measure the retreat of ice sheets over the Antarctic continent.
While more than three-quarters of Antarctica were found to be stable, the remainder of the continent has experienced rapid melting over the last 30 years, according to the new study published in theProceedings of the National Academy of Sciences.
The regions losing ice the fastest are West Antarctica, the Antarctica Peninsula and parts of East Antarctica. Nearly 5,000 square miles of grounded ice have been lost since 1996, the researchers said.
The research includes a comprehensive mapping of the grounding line --the boundary where ice sheets separate from the bedrock and begin to float on the ocean-- which has been the "gold standard" for documenting ice sheet stability, Eric Rignot, professor of earth system science at UC Irvine and lead author of the paper, said in statement. This is the first time the grounding line in Antarctica has been mapped over such a long time span, Rignot said.
There has been no grounding line migration for 77% of Antarctica's coastline. However, the ice sheet has been retreating from the grounding line in the most vulnerable regions at a rate of more than 170 square miles per year.
The most dramatic changes occurred in the Amundsen Sea and the Getz section in West Antarctica, where glaciers retreated up to 25 miles. Pine Island Glacier retreated more than 20 miles, Thwaites Glacier retreated more than 16 miles, and Smith Glacier retreated 26 miles.
"Where warm ocean water is pushed by winds to reach glaciers, that’s where we see the big wounds in Antarctica," Rignot said.
Glaciologists have taken a particular interest in Antarctica's western shelf due to its potential to cause a severe rise in sea levels. Thwaites Glacier, also known as the "Doomsday Glacier," already contributes to 4% ofoverall sea level rise, while Pine Island Glacier is Antarctica’sfastest-melting glacier.
If the WestAntarcticaIce Sheet were to collapse in its entirety, it has the potential to contribute up to9 feet in sea level rise, researchers say.
The intrusion of warm water below the ice sheets explains most of the retreat patterns in Western Antarctica, but the significant grounding line migration along the Antarctic Peninsula, which sits on the northeast part of the continent, is not as clear, the researchers said. There is no evidence of warm water in that region, Rignot said.
"Something else is acting -- it’s still a question mark," Rignot said.
Every three years, vulnerable regions of Antarctica are losing the grounded ice equivalent to Los Angeles, the researchers said.
"The flip side is that we should perhaps feel fortunate that all of Antarctica isn’t reacting right now, because we would be in far more trouble," Rignot said. “But that could be the next step."
