格陵兰冰盖表面消融研究进展

冰盖表面消融是格陵兰冰盖物质平衡的重要组成部分, 已成为近年来格陵兰冰盖研究的热点. 格陵兰冰盖表面消融研究的关键在于理解冰盖融水的产生、 运移和释放等水文过程, 需要解决如下关键科学问题: 1) 冰盖表面产生了多少融水;2)冰盖表面水文系统具有什么特征; 3)冰盖表面融水如何影响冰盖运动; 围绕这些科学问题, 总结了格陵兰冰盖表面消融的研究进展. 冰盖表面消融建模、 冰盖表面湖的信息提取与面积特征变化、 深度反演与体积量算等是目前研究冰盖表面融水量的主要途径, 冰盖表面湖、 冰盖表面径流、 锅穴与冰裂隙等表面水文要素的空间分布规律研究则可用于揭示冰盖表面水文系统特征, 冰盖表面融水与冰盖运动速率的关系、 表面融水进入冰盖内部与底部的水文过程是目前揭示表面融水如何影响冰盖运动的主要手段.

The Progress of Greenland Ice Sheet Surface Ablation Research

Surface ablation has great impact on the Greenland Ice Sheet (GrIS) mass balance and becomes the focus of GrIS research in recent years. The production, transportation and release of meltwater are the keys to understand the potential impact of the GrIS surface ablation. These hydrological processes could illustrate the following problems: How much meltwater is produced atop the GrIS? What are the characteristics of meltwater-formed supraglacial hydrological system? How does the meltwater influence the GrIS motion? Ablation modeling is an important approach to acquire surface ablation information. Areas, depths, and volumes of supraglacial lakes extracted from remotely sensed imageries provide direct meltwater information. The spatial distribution of supraglacial lakes, supraglacial streams, moulins and crevasses demonstrates the characteristics of supraglacial hydrological system, which is in charge of meltwater transportation. The release of meltwater into englacial and subglacial ice sheet has important but undetermined impact on the GrIS motion. The relationship between surface meltwater volume and GrIS motion velocity is employed to understand the impact.