20世纪以来西藏冰湖溃决灾害事件梳理

Study on the Glacial Lake Outburst Flood Events in Tibet since the 20th Century

冰湖溃决洪水(泥石流)是西藏自治区主要自然灾害之一,对已溃决冰湖特征及灾害影响范围与程度的认识是判定冰湖溃决条件、构建冰湖溃决评价指标体系以及开展冰湖溃决洪水估算与模拟的基础。通过对已溃决冰湖灾害事件文献及资料整理,结合地形图、遥感影像、中国冰川编目数据、Google Earth、冰湖溃决遗迹记录及野外考察,系统梳理了20世纪以来西藏地区发生的27次冰湖溃决事件,从多个角度判定并给出了23个已溃决冰湖所在的地理位置,并对金错、印达普错和次拉错冰湖溃决事件描述进行了勘误,指出1982年8月27日在定结县发生的冰湖灾害事件应是印达普错溃决所导致,2009年7月29日在边坝县发生溃决的冰湖是错嘎,而非次拉错。

Glacial lake outburst flood(GLOF) and debris flow is one of the main natural hazards in Tibet Autonomous Region. The investigation of characteristics of glacial lake outburst and its affected region and damage degree is the basis for the study on GLOFs or debris flow, such as judging the outburst conditions, building the evaluation index system of glacial lake outburst and modeling the GLOFs or debris flow. Based on the review on the numerous literatures, this paper systematically investigated 27 GLOF events took place in Tibet since the 20 th century by using the topographic maps, remote sensing images, Google Earth software, geomorphological characteristics records of GLOF??s damage and in-situ investigations. The geographical positions of 23 glacial lakes outburst were accurately identified from the annotation of glacial lake name in topographic map, the name of gully or village where GLOF occurred, the name or morphological characteristics of supply glacier, the feature or remain of glacial lake and new findings by field investigation. Finally, some mistakes on GLOF comprehension were rectified. Specifically, the GLOF event happened in Dinggyê County on August 27, 1982 was caused by Yindapu Co Lake, not Jin Co Lake.And the break of Cuoga Lake, not Cila Co Lake resulted in the GLOF occurrence on July29, 2009 in Banbar County.