Estimating glacier mass balance in the source region of the Yangtze River during 2000—2020 through InSAR
This paper aims to estimate glacier mass balance in the source region of the Yangtze River, to investigate the factors that affect glacier mass balance, and to reveal the impacts of glacier mass changes on the runoff of the rivers. In particular, the InSAR technique and bistatic TerraSAR-X/TanDEM-X images were utilized to generate two DEMs that cover most of glaciers in the source region of the Yangtze River. The new DEMs were then differenced with SRTM DEM to obtain glacier thickness changes during 2000—2012 and 2000—2020, and a glacier mass density was used to converted the glacier thickness changes in-to glacier mass balance. The discrepancy between the derived glacier mass balance and the field measured glacier mass balance is only 0.03m w.e.a-1, indicating a high precision of the results. The glacier mass balance in source region of the Yangtze River during 2000—2012 and 2000—2020 were (-0.30±0.02)m w.e.a-1 and (-0.45±0.04)m w.e.a-1, respectively. Glacier melting during 2012—2020 apparently intensified relative to that during 2000—2012. Rise of summer temperature and decease of summer precipitation were deemed as the main cause of glacier mass loss. Moreover, the glacier melting rate decrea-ses from the southeastern part to the northwestern part of the study area. Lower summer temperature, smaller temperature rising speed, higher glacier altitude, higher glacier accumulation area ratio, steeper glacier surface of the west area may account for this phenomenon. During 2000—2020, the glacier mass loss in the basin of the Tuotuo River contributed 4.4％ of the run-off of the Tuotuo River, and those in the basins of the Tuotuo River and the Dangqu River contributed 2.5％ of the runoff of the Tongtian River, indicating that glacier mass loss had slight impact on the runoff the upper reaches of the Yangtze River.
source region of the Yangtze Riverglacier mass balanceTanDEM-X imagesmeltingrunoff
万方数据
维普
