中国科学院张国庆和奥地利格拉茨技术大学Bolch Tobias等研究发现，高喜马拉雅地区湖泊终端冰川的质量损失被低估。这一研究成果发表在2023年4月3日出版的国际学术期刊《自然—地球科学》上。

课题组研究人员使用多时相卫星数据和实证面积-体积的关系，来估测高喜马拉雅地区冰川湖的体积变化，并量化由于湖水替代冰造成的水下质量损失。研究发现，从2000-2020年，冰前湖泊的数量、面积和体积不断增加，分别增加到此前的47％，33 ±2%和42±14%。且在2000-2020年间，冰川湖的扩张导致了2.7 ±0.8 Gt的冰川质量损失，表明此前对高喜马拉雅地区湖泊终端冰川总质量损失的估测被低估了6.5 ± 2.1%。区域性的，被最大程度(10 ±4%)低估的区域位于喜马拉雅的中部，也就是冰川湖扩张最快的区域。

研究人员的估计减少了总冰川质量损失的不确定性，为冰川水文模型提供了重要数据，也给这一敏感山区的水资源管理提供了支持。

据介绍，长期卫星观测有助于量化冰川的质量变化和水圈对冰川变化的反应。然而，此前研究人员使用大地测量方法时，没有考虑与湖泊终端相关的水下质量损失，导致冰川质量损失被低估。

附：英文原文

Title: Underestimated mass loss from lake-terminating glaciers in the greater Himalaya

Author: Zhang, Guoqing, Bolch, Tobias, Yao, Tandong, Rounce, David R., Chen, Wenfeng, Veh, Georg, King, Owen, Allen, Simon K., Wang, Mengmeng, Wang, Weicai

Issue&Volume: 2023-04-03

Abstract: Long-term satellite-based observations have helped quantify glacier mass change and the response of the hydrosphere to glacier changes. However, subaqueous mass loss associated with lake-terminating glaciers is not accounted for in geodetic methods, leading to an underestimation of glacier mass loss. Here we use multi-temporal satellite data and an empirical area–volume relationship to estimate the volume change of glacial lakes across the greater Himalaya and quantify subaqueous mass loss due to the replacement of ice with lake water. We show that proglacial lakes have increased 47% by number, 33±2% by area and 42±14% by volume from 2000 to 2020. The expansion of glacial lakes has resulted in 2.7±0.8Gt of subaqueous mass loss between 2000 and 2020, such that the previous estimate of total mass loss of lake-terminating glaciers in the greater Himalaya is underestimated by 6.5±2.1%. Regionally, the largest underestimation (10±4%) occurred in the central Himalaya, where glacial lake growth has been the most rapid. Our estimates reduce uncertainties in total glacier mass loss, provide important data for glacio-hydrological models and therefore also support the water recources management in this sensitive mountain region.

DOI: 10.1038/s41561-023-01150-1

Source: https://www.nature.com/articles/s41561-023-01150-1