青藏高原东南部海洋型冰川物质平衡研究进展北大核心CSCD

青藏东南部海洋型冰川具有独特的气候敏感性,普遍呈现加速退缩趋势,这不仅影响区域水资源安全,而且伴生了相应的冰川灾害,是当前青藏高原冰冻圈变化研究的热点区域之一。本文对海洋型冰川物质平衡时空变化特征进行了综述,2000年以来冰川总体处于物质亏损状态,其平均物质平衡介于-0.66~-0.61m w.e.·a^(-1)之间;同时总结了海洋型冰川物质加速变化的驱动因素以及新特征。当前海洋型冰川物质平衡变化研究受观测数据缺乏和模型模拟不确定性等问题限制,尤其现有模型对冰面裂隙增多与扩张、冰崖-冰面湖-表碛相互作用、冰内冰下过程、冰崩、末端冰湖水-冰相互作用等过程的描述过于简化或基本缺失,其机理及影响仍存在较大的不确定性。未来需加强海洋型冰川物质平衡的综合监测,基于多数据和多方法的集成研究提高模型对冰川物质平衡多物理过程的耦合与模拟能力,为开展海洋型冰川物质变化的区域水资源效应和致灾效应研究奠定基础。

Review of maritime glacier mass balance in the southeastern Tibetan Plateau

Maritime glaciers mainly concentrate in the southeastern Tibetan Plateau， including the Hengduan Mountains， central and eastern Nyainqentanglha Mountains and eastern Himalayas， which show higher mass loss and accumulation and ice temperature compared to other glacier types， with relatively fast ice velocity. Maritime glaciers show the unique sensitive to the changing climate and have experienced the most dramatic mass loss over the past decades， with important consequences for assessing regional water resource availability and glacial hazards risk. It has become a hotspot for the cryosphere change of the Tibetan Plateau. This study summarizes the spatial and temporal characteristics of mass balance of maritime glaciers， and reviews the driving factors of accelerated mass change and new features of mass change of maritime glaciers. As a consequence of continuous temperature rising， precipitation changing and spatially distributed debris cover， maritime glaciers has been expriencing dramatic mass loss since the year of 2000， on which the average mass balance varies from -0.66 to -0.61 m w.e.·a^-1. In particular， these glaciers experience an accelerating trend in mass loss over the past ten years. However， the current studies on maritime glacier mass balance still suffers from insufficient observational data and uncertainties of model simulations. In particular， the existing models are oversimplification or basically missing in discribing the processes such as ice crevasse enlargement， interaction between ice cliff， supraglcail pond and debris cover， englacial and subglacial system and ice avalanche as well as the interaction between ice and water at the terminus of lake-terminating glaciers， and their mechanisms and impacts are still uncertain. This study motivates further effort to further develop the monitoring system of maritime glacier mass balance， and improve models’ ability to couple the multi physical processes of glacier mass balance through conducting integrated research based on multi-data and multi-approaches. Overall， this study draws an intergrated view of understanding the characteristics of maritime glacier mass change and associated driven factors in the southeastern Tibetan Plateau， which provides a foundation for understanding and predicting the status of maritime glaciers and their responses to climate change as well as assessing the vulnerability of regional water resources and glacier-related hazards in the southeastern Tibetan Plateau.