Glacier and lake variations in the Yamzhog Yumco basin, southern Tibetan Plateau, from 1980 to 2000 using remote-sensing and GIS technologies

Glacier and lake variations in the Yamzhog Yumco basin in southern Tibet were studied by integrating series of spatial data from topographic maps and Landsat images at three different times: 1980, 1988/90 and 2000. The results indicate that the total glacier area has decreased from 218 km(2) in 1980 to 215 km(2) in 2000, a total reduction of 3 km(2) (i.e. a 1.5% decrease). Glacier recession rates were clearly larger in the 1990s than the 1980s due to the warmer climate. The total lake area decreased by about 67 km(2) during 1980-90 and increased by 32 km(2) during 1990-2000. It is suggested that change of lake area in the basin was rapid and most likely caused primarily by the change in precipitation and evaporation in the basin, and secondarily by the increased water supply from melting glaciers.