世界上最宽的冰川正以“更具侵略性”的速度融化，超出早先的预测。由冰川学家团队进行的新研究显示，其对全球海平面上升的影响可能是目前估计的两倍。新研究发现西南极的泰特斯冰川因其崩塌可能造成严重破坏而被称为“末日冰川”，正如CNN所报道的。该冰川使得科学家难以预测未来的海平面上升。据CNN报道，加州大学欧文分校和NASA喷气推进实验室的冰川学家们开发了一种新的冰盖模型，以更好地理解冰川下方发生的情况。
The world’s widest glacier is melting “more aggressively” than earlier projections said. According to new research by a team of glaciologists, its effect on global sea level rise could be twice the current estimates. What the new study foundThwaites Glacier in West Antarctica is known as the “Doomsday Glacier” because its collapse could cause serious damage, as per CNN. The glacier makes it difficult for scientists to predict future sea level rise. According to CNN, glaciologists from the University of California, Irvine, and NASA’s Jet Propulsion Laboratory developed a new ice sheet model to better understand what is happening beneath the glacier.
在将模型更新以包含“搁浅带”后，科学家们发现，泰特斯冰川到2100年可能使全球海平面上升多达1.2英寸。这一数字是早先估计的两倍，且即使没有进一步的全球变暖也可能发生。该研究成果于周一发表在《自然通讯》期刊上。难以预测的原因这座面积相当于佛罗里达州大小的冰川位于地球上最难到达的地区之一。它已经持续退缩了数十年。
After updating the model to include a “grounding zone,” the scientists found that Thwaites Glacier could add up to 1.2 inches to global sea levels by 2100. This is twice the amount predicted by earlier estimates, and it could happen even without further global warming. The findings were published Monday in the journal Nature Communications. Why it is hard to predictFlorida-sized glacier lies in one of the least accessible places on Earth. It has been retreating for decades.
其融化的冰目前约占全球海平面上升的4%。其退缩背后的原因非常复杂，这使得其未来走势难以绘制。什么是“搁浅带”？据CNN报道，该冰川的快速退缩是由其“搁浅线”处的过程驱动的。这是冰从海床升起并开始作为冰架漂浮在海洋上的点。典型的冰盖模型曾将搁浅线视为固定且基本稳定的。但正如报告的首席作者马蒂亚·波因内利所说，“我们已经认识到，在地球上主要终止于海洋的冰川之下存在着不同的安排。”
Its melting ice now adds around 4% to global sea level rise. The reasons behind its retreat are very complex, which makes its future hard to map. What is a ‘grounding zone’?According to CNN, the glacier’s rapid retreat is driven by processes at its “grounding line.”This is the point where the ice rises off the seabed and starts to float on the ocean as an ice shelf.A typical ice sheet models have treated the grounding line as fixed and mostly stable. But “we have come to acknowledge a different arrangement beneath Earth’s major ocean-terminating glaciers,” said the report’s lead author Mattia Poinelli.
波因内利是加州大学洛杉矶分校的项目科学家，在研究期间曾是加州大学欧文分校的地球系统科学研究员。据CNN报道，卫星数据显示，搁浅线实际上是一个“搁浅带”，有时宽达数英里。
He is a project scientist at UCLA who was an Earth system science researcher at UC Irvine at the time of the study. As per CNN, satellite data shows the grounding line is really a “grounding zone,” sometimes miles wide.
海水随潮汐在此进出，使厚冰被抬升和降低。这被称为“潮汐泵送”。据Poinelli称，这一过程使相对温暖的海水能够“深入冰盖下方并引发剧烈融化”。水下山脊可能不再阻挡冰川。据CNN报道，Thwaites冰川下方的土地呈下坡倾斜。随着冰川融化，更多冰面与温暖的海水接触。目前有两条水下山脊有助于阻挡冰流，防止其过快流入海洋。
Seawater flows in and out with the tides here, lifting and lowering the thick ice. This is called “tidal pumping.”According to Poinelli, this lets relatively warm ocean water get “deep underneath the ice sheets and causing vigorous melting.”Underwater ridges may no longer hold back the glacierAccording to CNN, the land beneath Thwaites Glacier slopes downward. As the glacier melts, more ice comes into contact with warm ocean water. Two underwater ridges currently help hold the ice back and stop it from flowing into the ocean too quickly.
研究发现，融化正导致冰缓慢脱离其中一条山脊——即Mouginot山脊。科学家估计，到本世纪末，冰脱离该山脊的概率为60%。如果发生这种情况，冰川可能会沿着倾斜的地面快速后退，朝着下一个主要山脊移动。为什么这很重要Thwaites冰川储存的水量足以在其崩塌时使海平面上升超过2英尺。它还像一个塞子一样，阻挡着巨大的南极冰盖。
The study found that melting is making the ice slowly detach from one of these ridges, called the Mouginot Ridge. Scientists estimate there is a 60% chance that the ice will break free from the ridge by the end of the century. If this happens, the glacier could retreat quickly down the sloping ground towards the next major ridge. Why it mattersThwaites holds enough water to raise sea levels by more than 2 feet if it collapses. It also acts like a cork holding back the huge Antarctic ice sheet.
因此，其崩塌可能导致海平面上升约10英尺，这可能严重威胁从迈阿密到马尼拉的沿海社区。研究结果表明，失去Thwaites的影响可能被低估了。报告补充称，1.2英寸可能听起来不多，但足以显著增加沿海居民的危险。正如CNN所引用的，报告作者、加州大学欧文分校地球系统科学教授Eric Rignot表示：“这些结果‘预测了未来几十年沿海洪水的风险和暴露程度将高于之前的预期’。”接下来会发生什么据CNN报道，Rignot表示，下一步是获取搁置线的观测数据。
So its collapse could lead to around 10 feet of sea level rise, which could badly hurt coastal communities from Miami to Manila. The findings suggest the impact of losing Thwaites may have been underestimated. It added that 1.2 inches may not sound like much, but it is enough to greatly increase dangers for coastal people. The results “predict greater risk of and exposure for coastal flooding than anticipated in the coming decades,” said Eric Rignot, a report author and professor of Earth system science at UC Irvine, as per CNN. What happens nextAs per CNN, Rignot said the next step is to get observational data from the grounding line.
科学家们计划于2028年前往那里，安装仪器记录海水进出的流动情况。里尼奥表示：“几十年来，我们一直意识到气候变化对地球敏感冰盖的影响。”但近年来，人们对像泰特斯冰川这样的冰川底部到底发生了什么有了越来越深刻的认识，这导致了更强烈的警报感。”他说，世界必须现在就减少导致地球变暖的污染，以限制其影响。但他警告说：“即使我们这样做了，也只能预期未来海平面会因已经造成的损害而继续上升。”
The scientists plan to travel there in 2028 and set up instruments to record the flow of seawater in and out.“We have been aware of the impacts of climate change on our planet’s sensitive ice sheets for decades,” Rignot said, “but a mounting realization gained in recent years of what is really happening on the undersides of glaciers like Thwaites is leading to an even greater sense of alarm.”He said the world must cut planet-heating pollution now to limit the impacts. But he warned, “even if we do, we can expect higher sea levels in the future resulting from the damage that has already been done.”