干旱区生态环境知识资源中心

Chongce Ice Cap (35 degrees 14’N, 81 degrees 07’E), located in the south margin of Taklimakan Desert, West Kunlun Mts. of China was sampled by coring in 1992, and this provides us with climate proxy of high altitudes (6,530 m). Through analyzing the weather observation stations surrounding Taklimakan Desert, the climate record of Hotan station was chosen to be the representative of low altitudes. Wavelet analysis were used to investigate the climatic variations of patterns, cycles and frequencies of different altitudes from 1954 to 1992, and different responses of different altitude surrounding Taklimakan Desert to global warming were recorded: (1) coherent decline of snow accumulation rate and dust deposition of high altitude recorded in Chongce ice core; (2) coherent increase of summer half-year precipitation and SAT of Hotan; (3) consistent variation tendency between dust deposit recorded in Chongce ice core and Hotan spring sandstorm days; (4) opposite variation tendency between Hotan precipitation and Chongce ice core snow accumulation rate and consistent cycles in general. By analyzing the mechanism of different responses, the predominant factors were determined of different altitudes: (1) at the low altitude, the vapor supply is predominant, and more vapor supplying means more precipitation; (2) at the high altitude, probably the population of dust aerosols which act as cloud ice nuclei in high altitude takes advantage over the vapor supply to affect the precipitation, and so the dust aerosol population reducing results in the wet deposition being reduced, thus the dust aerosol is the predominant factor.