Summer is prime iceberg season in Greenland’s glacier-fed fjords, and 2026 was no exception. Especially notable was the berg that broke from the Petermann Glacier along Greenland’s northwest coast in August. Roughly the size of St. Thomas in the U.S. Virgin Islands, it was the largest calving event by any Arctic glacier since 2020.
夏季是格陵兰岛冰川滋养的峡湾的主要冰山季节，2026 年也不例外。尤其值得注意的是八月份从格陵兰岛西北海岸的彼得曼冰川上脱落的冰山。它的大小大约相当于美属维尔京群岛圣托马斯岛的大小，是 2020 年以来北极冰川最大规模的崩解事件。
Iceberg calving is a routine part of an outlet glacier’s life cycle. Scientists watch the process closely, however, along with numerous other observations of the ice and its environment, for longer-term signs of instability . Petermann is one of Greenland’s largest marine-terminating glaciers and acts as a gatekeeper for ice flowing from the ice sheet into the ocean. Its future stability has implications for sea level rise .
冰山崩解是出口冰川生命周期的常规部分。然而，科学家们密切关注这一过程，以及对冰及其环境的许多其他观察，以寻找长期不稳定的迹象。彼得曼是格陵兰岛最大的海洋终止冰川之一，是冰从冰盖流入海洋的看门人。其未来的稳定性会对海平面上升产生影响。
The calving event of summer 2026 was spotted on August 4 by Adam Garbo, a doctoral student in glaciology at the University of Ottawa, in imagery from the European Space Agency’s Sentinel-1 mission. Garbo and an international team of colleagues have been using remote sensing to study and track the glacier’s ice tongue.
8 月 4 日，渥太华大学冰川学博士生 Adam Garbo 在欧洲航天局 Sentinel-1 任务的图像中发现了 2026 年夏季的冰崩事件。嘉宝和一个国际同事团队一直在利用遥感技术来研究和追踪冰川的冰舌。
The team reported that the large tabular iceberg, or “ice island,” measured just over 76 square kilometers (29 square miles) at the time it calved—the largest to break from the glacier since the ice island of 2012 (130 square kilometers). The 2012 calving followed earlier major events in 2008 (31 square kilometers) and 2010 (just over 250 square kilometers).
研究小组报告称，这座巨大的板状冰山或“冰岛”在崩解时的面积刚刚超过 76 平方公里（29 平方英里），这是自 2012 年冰岛（130 平方公里）以来从冰川中破裂出来的最大冰山。 2012 年的产犊是继 2008 年（31 平方公里）和 2010 年（刚刚超过 250 平方公里）的重大事件之后发生的。
The August 2026 event could have been even bigger. Garbo and colleagues had been expecting a major calving once one of the large rifts they were monitoring finally cut all the way across Petermann’s ice tongue. “What surprised us was that the calving instead followed a different fracture, producing a smaller ice island than we had originally anticipated,” Garbo said. As of late August, two large rifts remained and were expected to eventually produce new ice islands of roughly 94 square kilometers and 84 square kilometers, though the timing remained uncertain.
2026 年 8 月的活动本来可以规模更大。嘉宝和同事们一直预计，一旦他们监测的大裂缝之一最终完全穿过彼得曼的冰舌，就会发生重大的崩解。嘉宝说：“令我们惊讶的是，崩解是在不同的断裂之后发生的，产生了一个比我们最初预期的更小的冰岛。”截至8月下旬，两个大裂谷依然存在，预计最终将产生约94平方公里和84平方公里的新冰岛，但具体时间仍不确定。
Glaciologist Mauri Pelto of Nichols College has also been tracking the iceberg , using images from NASA-USGS Landsat satellites, as it drifted down Petermann Fjord toward Nares Strait. In the week since it calved, the berg drifted an average of 3 kilometers per day. It continued toward the fjord’s junction with Nares Strait , where it rammed into a small rocky outcrop known as Joe Island (Joe Ø). The brief encounter is visible in images captured by the OLI (Operational Land Imager) on Landsat 9 on August 23 (top right) and August 24 (top left). A detailed view of the August 24 image is shown above.
尼科尔斯学院的冰川学家莫里·佩尔托也一直在利用美国宇航局-美国地质调查局陆地卫星的图像来追踪这座冰山，当时它沿着彼得曼峡湾漂向内雷斯海峡。自诞生以来的一周内，冰山平均每天漂移 3 公里。它继续向峡湾与纳雷斯海峡的交汇处冲去，撞上一个名为乔岛 (Joe Ø) 的小岩石露头。从陆地卫星 9 号 OLI（操作陆地成像仪）于 8 月 23 日（右上）和 8 月 24 日（左上）拍摄的图像中可以看到这次短暂的相遇。上面显示了 8 月 24 日图像的详细视图。
Joe Island sits at the mouth of Petermann Fjord, making it one of the first obstacles a departing ice island meets. Collisions with it—like the one that split the 2010 ice island in two—often mark the start of a berg’s breakup. Petermann bergs tend to be thinner and more fragile than those calved by glaciers such as Greenland’s Jakobshavn and Helheim, and thinner still than Antarctica’s behemoths, Pelto noted.
乔岛位于彼得曼峡湾的入口处，使其成为离开冰岛时遇到的第一个障碍。与它的碰撞——就像2010年将冰岛一分为二的碰撞——通常标志着冰山分裂的开始。佩尔托指出，彼得曼冰山往往比格陵兰岛雅各布港和赫尔海姆等冰川崩解的冰山更薄、更脆弱，甚至比南极洲的庞然大物还要薄。
“We were certainly watching closely as it interacted with Joe Island and were impressed that it survived the interaction without further fragmentation,” Garbo said.
嘉宝说：“当它与乔岛互动时，我们确实在密切关注，并且印象深刻的是，它在互动中幸存下来，没有进一步分裂。”
The ice island was estimated to be less than 150 meters thick at the time of calving. Wind and surface currents have swept it out of the fjord, and satellite images show it pivoting away from Joe Island and continuing southwest through Nares Strait. As it drifts, it will fracture into smaller pieces as tides, winds, currents, and melting continue to weaken the ice.
据估计，冰岛在崩解时厚度不足150米。风和海面洋流将其吹出了峡湾，卫星图像显示它从乔岛转向西南，穿过内雷斯海峡继续向西南方向移动。当它漂移时，随着潮汐、风、洋流和融化继续削弱冰层，它会碎裂成更小的碎片。
Thicker bergs that calve from tidewater glaciers without floating ice-shelf extensions can drag and even become grounded on the seafloor within the fjord, while ice islands, like those from Petermann, might run aground later in their drift. Many ice islands have become “grounded” off the coasts of Coburg and Baffin islands.
从潮水冰川崩解而没有漂浮冰架延伸的较厚冰山可能会拖曳甚至在峡湾内的海底搁浅，而像彼得曼那样的冰岛可能会在漂流过程中稍后搁浅。许多冰岛已在科堡岛和巴芬岛海岸“搁浅”。
Garbo and colleagues noted that ice islands and their fragments have been known to travel considerable distances, posing potential hazards to marine activities and infrastructure while also distributing freshwater through the ocean as they melt.
嘉宝及其同事指出，众所周知，冰岛及其碎片会移动相当长的距离，对海洋活动和基础设施构成潜在危害，同时在融化时还会通过海洋分配淡水。
NASA Earth Observatory images by Lauren Dauphin, using Landsat data from the U.S. Geological Survey . Story by Kathryn Hansen.
NASA 地球观测站图像由 Lauren Dauphin 使用美国地质调查局的陆地卫星数据拍摄。凯瑟琳·汉森的故事。