Some Antarctic icebergs linger close to home for decades, running aground near the ice shelves that spawned them or circling partway around the continent on coastal currents. Others, like Iceberg A-81, make a faster exit, heading north out of the Weddell Sea along a route well-traveled by the region’s bergs.
一些南极冰山在家乡附近徘徊了数十年，在产生它们的冰架附近搁浅，或者在沿海洋流中绕着大陆旋转。其他冰山 A-81 等则以更快的速度退出，沿着该地区冰山经常行走的路线向北离开威德尔海。
Fast is relative, though. After breaking from the Brunt Ice Shelf in January 2023, the roughly 1,550-square-kilometer (600-square-mile) berg spent more than three years in the Weddell Sea, carried along the coast by the clockwise-flowing Weddell Gyre. By May 2026, it reached the tip of the Antarctic Peninsula. It then moved north into the Scotia Sea, and by late October 2026, it approached the remote island of South Georgia in the South Atlantic Ocean, 2,300 kilometers (1,400 miles) north-northwest of the Brunt Ice Shelf.
不过，快是相对的。这座约 1,550 平方公里（600 平方英里）的冰山于 2023 年 1 月脱离布伦特冰架后，在顺时针流动的威德尔环流的带动下，在威德尔海中度过了三年多的时间。到2026年5月，它到达了南极半岛的顶端。随后，它向北进入斯科舍海，到 2026 年 10 月下旬，它接近了位于布伦特冰架西北偏北 2,300 公里（1,400 英里）处的南大西洋偏远岛屿南乔治亚岛。
This image, acquired by the MODIS (Moderate Resolution Imaging Spectroradiometer) on NASA’s Terra satellite, shows the berg on October 20. In the days before, its progress slowed noticeably, and it appeared to be bumping along the edge of the island’s underwater shelf, according to Jan Lieser of Australia’s Bureau of Meteorology and Christopher Shuman of the University of Maryland (retired). South Georgia has slowed and even stopped icebergs before. In 2025, for instance, Iceberg A-23A ran aground on the shelf and later broke apart .
这张图像是由美国宇航局 Terra 卫星上的 MODIS（中分辨率成像光谱仪）拍摄的，显示了 10 月 20 日的冰山。澳大利亚气象局的扬·利瑟 (Jan Lieser) 和马里兰大学的克里斯托弗·舒曼 (Christopher Shuman)（已退休）表示，在之前的几天里，冰山的移动速度明显放缓，而且似乎沿着岛屿水下架的边缘颠簸。南乔治亚岛以前曾减缓甚至阻止了冰山的形成。比如2025年，冰山A-23A搁浅在架子上，后来解体。
Though Iceberg A-81 was a steadfast traveler once it broke free, it took its time in becoming an iceberg in the first place. For about 35 years, one of the Brunt Ice Shelf’s rifts known as Chasm 1 was relatively stable. Then, around 2012, it began growing again, and by 2019, it was advancing quickly enough that a break seemed imminent . But the floating glacial ice held on for several more years until finally, in January 2023, the berg let go .
尽管冰山 A-81 在挣脱束缚后会坚定不移地行走，但它从一开始就变成了一座冰山。大约 35 年来，布伦特冰架的裂缝之一（被称为“Chasm 1”）相对稳定。然后，在 2012 年左右，它再次开始增长，到 2019 年，它的增长速度足够快，以至于突破似乎迫在眉睫。但漂浮的冰川又坚持了几年，直到 2023 年 1 月，冰山最终松动。
Calving is a normal part of the life cycle of ice shelves, but scientists keep a close eye on Brunt, which has recently shed several large icebergs in quick succession and is home to the British Antarctic Survey’s Halley Research Station , a major base for Earth, atmospheric, and space science research since the 1950s. Besides A-81, the ice shelf calved Iceberg A-74 from the North Rift in 2021 and Iceberg A-83 from the Halloween Crack in 2024. A-74 has since broken up, while A-83 remains intact and is trailing A-81 northward, along with a handful of other icebergs that appear to be clearing out of the Weddell Sea.
冰架崩解是冰架生命周期的正常组成部分，但科学家们密切关注着布伦特岛，该冰山最近连续快速脱落了几座大型冰山，也是英国南极调查局哈雷研究站的所在地，该站是自 20 世纪 50 年代以来地球、大气和空间科学研究的主要基地。除了 A-81 之外，冰架还于 2021 年从北裂谷分裂出冰山 A-74，并于 2024 年从万圣节裂缝分裂出冰山 A-83。A-74 此后已解体，而 A-83 保持完整，并尾随 A-81 向北移动，还有一些其他冰山似乎正在从威德尔海消失。
NASA Earth Observatory image by Michala Garrison, using MODIS data from NASA EOSDIS LANCE and GIBS/Worldview . Story by Kathryn Hansen.
NASA 地球观测站图像，由 Michala Garrison 拍摄，使用来自 NASA EOSDIS LANCE 和 GIBS/Worldview 的 MODIS 数据。凯瑟琳·汉森的故事。