Modern Environment and Climate Record in the Dasuopu Ice Core

【摘要】：正 Dasuopu glacier,next to Xixiabangma Peak,provides a preferable medium forinvestigating climate and environment over the Tibetan Plateau because of its special location.Toits south is the south slope of the Himalayas which is wet and warm,to its north is the maimland ofthe Tibetan Plateau which is dry and cold.Situated at 7000m asl,Dasuopu glacier provides achance to inveshgate the atmospheric environment of the upper troposphere.From ourmeteorological observations,Sep.22,1997 is an important day.Before Sep.22 Xixiabangmaregion was snowy,while after that it was windy.In 1996 and 1997,we drilled a series of ice cores over 7000 m asl from the Dasuopu glacier.Here some results of 20m ice core drilled in 1996 are discussed.The core was dated back to 1983and the recovered accumulation decreased from 1983 to 1995.518O recorded in the core relats tothe amount effect,which increased from 1988.Cation data reveals that the Dasuopu glacier isslighily affected by dust generated in alid and send-arid region because of its altitude.TheDasuopu glacier receives most of its precipitation from summer plateau monsoon circulation.Thishas been demonstrated by not only the agrement between precipitation in India and accumulationin the core but also the results of meteorological observations.We also investigated theaccumulation effect on Na and Ca.The results indicated a negative correlation betweenaccumulation and normalized Ca and a positive correlation between accumulation and normalizedNa.The former is because more precipitation will prevent dust geneation in arid and semi-aridregion.The latter is beeause Na in this glacier mainly come from the ocean,which has also beendemonstrated by agreement between C1 and Na ratios in the Dasuopu ice core and in bulkseawarer.Finally,we inveshgated the Dasuopu glacier from spatial aspect by comparison with otherglaciers.We defined Ca/Na as a continent degree.The higher ratio of Ca/Na of a glacier is thegreater distance between the glacier and the Ocean.The Dasuopu glacier is located at climaticdivide.The investigation can be helpful to understand monsoon and dust transportation.

【基金】：Under the auspices of the National(G19980408) CAS’s Key Project for Basic Research on Tibetan Plateau(KZ951-A1-204,KZ95T-06)
【分类号】：P532