摘要
青藏高原作为全球气候变化的敏感区域,其冰川和湖泊变化对气候系统具有重要影响。基于2000—2023年遥感影像数据,选取青藏高原的典型冰川和湖泊,融合归一化差异积雪指数(normalized difference snow index,NDSI)和Glacier-Unet方法提取冰川面积,结合归一化差异水体指数(normalized difference water index,NDWI)与双极化水体指数(sentinel dual-polarized water index,SDWI)提取湖泊面积。同时,利用相邻气象站的年平均气温和年降水量数据,通过主成分分析定量揭示气温升高通过增强消融作用直接驱动冰川退缩,降水增加则通过增强入湖补给主导湖泊扩张。结果表明:(1)7座典型冰川面积累计减少20.75 km^(2),退缩速率呈现由低纬度向高纬度递减的特征。气温是冰川退缩的主要驱动,不同冰川对气温升高的响应时序与幅度存在差异,但均体现出长期升温背景下消融增强、积累减弱的大趋势。(2)10座典型湖泊呈现扩张趋势,总面积增加757.55 km2,扩张主要集中在中南部内流区湖泊。不同湖泊对降水变化的响应时序与幅度存在差异,但均体现出在长期降水增加背景下补给增强、蒸发与外流相对不足导致面积扩张的大趋势。
As a sensitive area to global climate change,the Qinghai-Tibet Plateau plays an important role in the climate system through the changes in glaciers and lakes.Based on the remote sensing imagery data from 2000 to 2023 and selected typical glaciers and lakes on the Qinghai-Tibet Plateau,the normalized difference snow index(NDSI)and Glacier-Unet method are used to extract the area of glaciers,and the area of lakes is extracted by combining the normalized difference water index(NDWI)and sentinel dual-polarized water index(SDWI).Meanwhile,by using the annual average temperature and annual precipitation data from neighboring weather stations,the principal component analysis is utilized to quantitatively reveal that rising temperatures directly drive glacier retreat by enhancing ablation,while the increased precipitation dominates lake expansion by enhancing lake inflow.The results are shown below.(1)The area of 7 typical glaciers decreases by 20.75 km^(2) cumulatively,and the retreat rate is decreasing from low latitude to high latitude.Temperature is the main driver of glacier retreat,and there are differences in the timing and magnitude of the response of different glaciers to the rising temperatures,but they all reflect the general trend of enhanced ablation and weakened accumulation in the context of long-term warming.(2)Ten typical lakes show an expansion trend,with the total area increasing by 757.55 km^(2),and the expansion is mainly concentrated in the endorheic lakes in the central-southern area.There are differences in the timing and magnitude of the response of different lakes to the changes in precipitation,but all of them reflect the general trend of expansion due to enhanced recharge and relatively insufficient evaporation and outflow in the context of long-term increase in precipitation.
作者
张秀再
许岱
杨昌军
张昊
ZHANG Xiuzai;XU Dai;YANG Changjun;ZHANG Hao(School of Electronic&Information Engineering,Nanjing University of Information Science&Technology,Nanjing 210044,China;Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology(CICAEET),Nanjing University of Information Science&Technology,Nanjing 210044,China;National Satellite Meteorological Center(National Center for Space Weather),Beijing 100081,China;Innovation Center for FengYun Meteorological Satellite(FYSIC),Beijing 100081,China;Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites,CMA,Beijing 100081,China)
出处
《海洋气象学报》
2026年第1期95-105,共11页
Journal of Marine Meteorology
基金
第二次青藏高原综合科学考察研究项目(2019QZKK0105)。
关键词
青藏高原
遥感
冰川退缩
湖泊扩张
气候驱动
the Qinghai-Tibet Plateau
remote sensing
glacier retreat
lake expansion
climate driving
