Journal of Geographical Sciences ›› 2008, Vol. 18 ›› Issue (2): 177-189.doi: 10.1007/s11442-008-0177-3

• Climate and Environmental Change • Previous Articles     Next Articles

The response of lake-glacier variations to climate change in Nam Co Catchment, central Tibetan Plateau, during 1970–2000

WU Yanhong1,3, ZHU Liping2   

  1. 1. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China|
    2. Institute of Tibetan Plateau Research, CAS, Beijing 100085, China|
    3. Graduate School of the Chinese Academy of Sciences, Beijing 100039, China
  • Received:2007-12-12 Revised:2008-02-03 Online:2008-06-25 Published:2008-06-25
  • Supported by:

    National Basic Research Program of China, No.2005CB422002; National Natural Science Foundation of China, No.40331006; No.40571172; Knowledge Innovation Project of the CAS, No.KZCX3-SW-339

Abstract:

Based upon the 1970 aero-photo topographic map, and TM/ETM satellite images taken in 1991 and 2000, the authors artificially interpreted boundaries of lake and glaciers in Nam Co Catchment, and quantified lake-glacier area variations in different stages by “inte-grated method” with the support of GIS. Results show that from 1970 to 2000, lake area in-creased from 1942.34 km2 to 1979.79 km2 at a rate of 1.27 km2/a, while glacier area de-creased from 167.62 km2 to 141.88 km2 at a rate of 0.86 km2/a. The increasing rate of lake in 1991–2000 was 1.76 km2/a that was faster than 1.03 km2/a in 1970–1991, while in the same period of time, the shrinking rates of glaciers were 0.97 km2/a and 0.80 km2/a respectively. Important factors, relevant to lake and glacier response to the climate, such as air tempera-ture, precipitation, potential evapotranspiration and their values in warm and cold seasons, were discussed. The result suggests that temperature increasing is the main reason for the accelerated melting of glaciers. Lake expansion is mainly induced by the increase of the gla-cier melting water, increase of precipitation and obvious decrease of potential evapotranspi-ration. Precipitation, evaporation and their linkages with lake enlargement on regional scale need to be thoroughly studied under the background of global warming and glacier retreating.

Key words: Tibetan Plateau, Nam Co Catchment, lake, glacier, remote sensing