The study of typical glaciers and lakes fluctuations using remote sensing in Qinghai-Tibetan Plateau

Glaciers and lakes on the Tibetan Plateau play an important role in the earth´s climatic system. The technologys of remote sensing and Geographic Information System (GIS) are quite efficient for us to analyze the status and fluctuation of glaciers and lakes. In this paper, the typical glaciers and lakes variations throughout the Tibetan Plateau are investigated by analyzing the datasets from aerial photos, satellite images, topographical and the derived digital elevation model (DEM) during the period of 1960-2000. The results show the variation of lake area strongly depends on local climate change. Over the past 30 years, most of lakes in middle Tibetan Plateau, such as the main lakes in the region of Selincuo Lake and Namucuo Lake, expanded and glaciers around the lakes retreated dramatically in Mt. Geladandong and Mt. Nyainqentanglha. We infer that the increasing of precipitation, decreasing of potential evaportranspiration and water runoff from glacier melting are mainly responsible for the lake expanding. However, the lakes in the source region of Yellow River in Northeast Plateau shrunk in the period of 1960-2000 despite of the glacier retreating in the area of Mt. A´nyemaqen. In the source region of Yellow River, the trend of precipitation, although positive, is not significant while temperature increased apparently and indicting water loss of the lake enhanced through increasing of evaportranspiration and thus lake shrunk in the past 30 years. Also we argue that ecosystem regression resulted from human activity in the region played an important role in the lake shrinking.