Abstract:

Using remote sensing image for the aeolian morphology and high resolution ancient monsoon indicators, the authors restore how the wind blows in Qaidam Basin since late Holocene. The results show that the prevailing winds of the basin were northwest winds, at the same time there were a small amount of westerly and north wind, with the summer monsoon and westerly circulation having little effect on the wind models. The eastern dune and Yardang landforms of the basin recorded the westerly winds of the last glacial, but the landforms in the midwest indicated that the Asian winter monsoon developed from the northwest during late Holocene. The changes in the atmospheric circulation model took place around 4000 aBP years ago, which was an important node, basin climate shifting from warm and humid to cold and dry.

Key words: Qaidam Basin, late Holocene, aeolian bedform, paleowind direction, East Asian onsoon

摘要：

利用遥感图像的风成地貌形态和高分辨率古季风指标, 恢复柴达木盆地晚全新世以来的古风况, 揭示青藏高原抬升时期东亚季风变迁的历史。结果表明, 柴达木盆地晚全新世以来盛行西北风, 同时有少量西风和北风, 主要由亚洲冬季风控制, 夏季风和西风环流的影响甚微。盆地东部沙丘和雅丹地貌记录了末次盛冰期西风环流的风向, 中西部地区的风成地貌指示晚全新世以来盆地发育西北向的亚洲冬季风。青藏高原的抬升阻挡西风环流进入柴达木盆地, 并加强亚洲冬季风, 造成盆地内古风向的改变, 大气环流模式的转变发生在4000 aBP左右, 此时是柴达木盆地气候从暖湿转向冷干的重要节点。

关键词: 柴达木盆地, 晚全新世, 风成地貌, 古风况, 东亚季风