近日，美国科罗拉多大学博尔德分校Naomi Ochwat团队发现了由冰平原崩解过程引起的地表冰川退缩记录。这一研究成果于2025年11月3日发表在《自然—地球科学》杂志上。

理解与预测入海冰川的不稳定性，已成为预报未来海平面上升所面临的最大挑战之一。此类不稳定的极端案例是南极半岛东部的赫克托里亚冰川，该冰川在2022年1月至2023年3月期间后退约25公里。

研究组主要通过地球物理数据和卫星影像分析，探讨了此次后退事件的动力学机制及驱动因素。研究发现，在拉森B湾持续存在十余年的定栖冰消失后，冰川立即开始后退，且其流速较定栖冰消失前加快近6倍，变薄速率增加40倍。

此外，2022年11月至12月期间，该冰川在两个月内总计后退8.2±0.2公里——后退速率比已有记录值快近一个数量级——并始于冰原区（该平坦区域仅存在浅层接地）从板状冰山崩解向浮力驱动崩解的转变。因此研究组得出结论：本次后退主要由冰原崩解过程导致，而非此前认为的大气或海洋环境因素。这表明具有冰原基底形态的入海冰川更容易发生失稳。

附：英文原文

Title: Record grounded glacier retreat caused by an ice plain calving process

Author: Ochwat, Naomi, Scambos, Ted, Anderson, Robert S., Winberry, J. Paul, Luckman, Adrian, Berthier, Etienne, Bernat, Maud, Antropova, Yulia K.

Issue&Volume: 2025-11-03

Abstract: Understanding and predicting marine-terminating glacier instability presents one of the greatest challenges to forecasting future sea level rise. An extreme case of such instability is the Hektoria Glacier on the Eastern Antarctic Peninsula, which retreated ~25km between January 2022 and March 2023. Here we investigate the dynamics and drivers of this retreat event primarily from analysis of geophysical data and satellite imagery. We find that retreat commenced immediately after the loss of decade-old fast ice in the Larsen B embayment and was associated with an almost 6-fold increase in flow speed and 40-fold increase in glacier thinning, relative to the period immediately before the fast ice loss. We also find that in November–December 2022, the glacier retreated a total of 8.2±0.2km in two months—a retreat rate nearly an order of magnitude faster than published values—and began with a transition from tabular iceberg calving to buoyancy-driven calving on an ice plain, a flat area where the glacier was only lightly grounded. Hence we conclude that in this case, retreat primarily resulted from an ice plain calving process, rather than atmospheric or oceanic conditions as suggested previously. This implies that marine-terminating glaciers with ice plain bed geometry can be easily destabilized.

DOI: 10.1038/s41561-025-01802-4

Source: https://www.nature.com/articles/s41561-025-01802-4