摘要
科西河流域冰川和冰湖较为发育,随着全球气候变暖,冰川融水成为冰湖扩张的重要补给,同时会引发冰湖溃决洪水(GLOF)等自然灾害,给当地居民生产生活带来巨大损失。因此,对该区域冰川冰湖的时空分布规律和变化特征的研究具有现实意义。本文基于Landsat系列遥感影像和数字高程模型,分析了1990—2020年科西河流域冰川冰湖面积时空分布与变化特征,并结合气象格点数据和GLOF事件,探究科西河流域冰川冰湖对气候变化响应及其与GLOF事件关系。结果表明:(1)1990—2020年科西河流域冰川面积呈加速退缩的趋势,近10年加速退缩趋势进一步加强。(2)科西河流域冰川主要分布在海拔4800~6800 m范围内,而在坡度上,主要分布在5°~20°。(3)1990—2020年科西河流域冰湖呈加速扩张的趋势,冰湖面积共扩张了26.09 km^(2),其中面积>0.25 km^(2)的冰湖扩张迅速;与冰川相连的冰湖面积扩张显著,面积增长率为49.39%。(4)1990—2020年科西河流域共11条冰湖发生溃决,溃决冰湖分布面积较小,介于0.02~0.7 km^(2)。(5)1990—2020年科西河流域气温和降水量呈波动增长趋势,降水增加不足以弥补温度引起的冰川退缩,致使科西河流域冰川加速退缩,冰湖加速扩张,冰湖溃决事件频发。
Glaciers and glacial lakes are well developed in the Koshi River basin.With global warming,glacial meltwater has become an important source of glacial lake expansion.At the same time,it will cause natural disasters such as glacial lake outburst flood(GLOF).Therefore,it is significant to study the temporal and spatial changes of glacial lakes in the region.In this paper,based on Landsat series remote sensing images and digital elevation model,the temporal and spatial distribution and variation characteristics of glacial lake area in the Koshi River basin From 1990 to 2020 are analyzed.The results show that:(1) From 1990 to 2020,the glacier area in the Koshi River basin showed an accelerating trend of retreat and the trend of accelerated retreat has been further strengthened in the past ten years.(2)The glaciers in the Koshi River basin are mainly distributed at an altitude of 4800~6800 m,with a slope of 5~20°.(3) From 1990 to 2020,the glacial lakes in the Koshi River basin have shown an accelerated expansion trend.The area of glacial lakes has expanded by 26.09 km^(2).The glacial lakes with an area of >0.25 km^(2) expanded rapidly.The area of glacial lakes connected to glaciers has expanded significantly,with an area growth rate of 49.39%.(4) From 1990 to 2020,a total of 11 glacial lakes in the Koshi River basin have burst,and some glacial lakes have completely burst or repeatedly burst.The area of glacial lakes is 0.02~0.7 km^(2).(5)From 1990 to 2020,the temperature and precipitation in the Koshi River basin showed a fluctuating growth trend resulting in accelerated retreat of glaciers,accelerated expansion of glacial lakes,and frequent occurrence of glacial lake outburst flood in the Koshi River basin.
作者
邓毅
冀琴
DENG Yi;JI Qin(College of Geography and Tourism,Chongqing Normal University,Chongqing 401331,China;The Key Laboratory of GIS Application,Chongqing 401331,China)
出处
《测绘通报》
CSCD
北大核心
2024年第10期58-63,97,共7页
Bulletin of Surveying and Mapping
基金
重庆市自然科学基金面上项目(CSTB2023NSCQ-MSX0990)
重庆市教委科学技术研究项目(KJQN202200526)
重庆师范大学基金项目(23XWB032)。
关键词
科西河流域
冰川退缩
冰湖扩张
气候响应
冰湖溃决洪水
Koshi River basin
glacier retreat
glacial lake expands
climate response
glacial lake outburst flood
