近日美国加州理工学院Greene, Chad A.的团队取得一项新突破。经过不懈努力，他们的研究揭示了1985年到2022年格陵兰冰盖的崩解普遍加速。相关论文于2024年1月17日发表在《自然》杂志上。

为了了解崩解前缘后退是如何影响格陵兰岛的冰质量平衡的，该团队研究人员结合1985年至2022年收集的236,328次人工手动生成和人工智能冰川终端位置观测数据，在近40年以来，每月生成一个120m分辨率的掩膜来定义冰盖范围。研究表明，自1985年以来，格陵兰冰盖(GrIS)的面积损失了5,091 ± 72 km²，相当于因后退损失了1,034±120 Gt的冰。研究结果显示，由于忽略了崩解前缘的后退，目前对冰盖质量平衡的普遍估计低于格陵兰岛最近的质量损失，低估幅度高达20%。

研究报告的质量损失对全球海平面的直接影响很小，但足以影响海洋环流和全球各地的热能分布。在季节时间尺度上，格陵兰岛每年都会损失193±25 km² (63±6Gt)的冰，从5月的最大范围后退到9月至10月的最小范围。研究强调，多年代际后退与每个冰川的季节性进退幅度高度相关，这意味着季节时间尺度上的终点位置变率，可以作为冰川对长期气候变化敏感性的指标。

据介绍，在过去的几十年里，几乎所有的格陵兰岛冰川都变薄或后退了，引发了冰川加速，海平面上升速度加快的后果，并对全球气候产生影响。

附：英文原文

Title: Ubiquitous acceleration in Greenland Ice Sheet calving from 1985 to 2022

Author: Greene, Chad A., Gardner, Alex S., Wood, Michael, Cuzzone, Joshua K.

Issue&Volume: 2024-01-17

Abstract: Nearly every glacier in Greenland has thinned or retreated over the past few decades1–4, leading to glacier acceleration, increased rates of sea-level rise and climate impacts around the globe5–9. To understand how calving-front retreat has affected the ice-mass balance of Greenland, we combine 236,328 manually derived and AI-derived observations of glacier terminus positions collected from 1985 to 2022 and generate a 120-m-resolution mask defining the ice-sheet extent every month for nearly four decades. Here we show that, since 1985, the Greenland Ice Sheet (GrIS) has lost 5,091 ± 72 km² of area, corresponding to 1,034 ± 120 Gt of ice lost to retreat. Our results indicate that, by neglecting calving-front retreat, current consensus estimates of ice-sheet mass balance4,9 have underestimated recent mass loss from Greenland by as much as 20%. The mass loss we report has had minimal direct impact on global sea level but is sufficient to affect ocean circulation and the distribution of heat energy around the globe10–12. On seasonal timescales, Greenland loses 193 ± 25 km² (63 ± 6 Gt) of ice to retreat each year from a maximum extent in May to a minimum between September and October. We find that multidecadal retreat is highly correlated with the magnitude of seasonal advance and retreat of each glacier, meaning that terminus-position variability on seasonal timescales can serve as an indicator of glacier sensitivity to longer-term climate change. 

DOI: 10.1038/s41586-023-06863-2

Source: https://www.nature.com/articles/s41586-023-06863-2