中昆仑山区封闭湖泊湖面波动及其气候意义

封闭湖泊湖面波动是气候变化很敏感的指示器,其水量平衡特征对此可给予理论证明,进而可将这种灵敏度表示为Z=A_l/A_b=(P_b-E_b)/(E_l—P_l)。中昆仑山区的封闭湖泊自17000a B.P.以来曾经历了三次高湖面,即17000a B.P.前后、12000a B.P.前后及8000—6000a B.P.。其中第一期的高湖面与高山区冰体消融、西风带位置的变动及土壤湿度、太阳辐射值的变化有关,第二次的高湖面是湖泊总体收缩下降过程中出现的相对稳定或短暂回升,第三期的高湖面是全球性温湿气候的产物。理论探讨与实例分析均说明,封闭湖泊湖面波动不仅对无人类观测记录的地质历史时期的气候变化有着重要的指示性,而且可以弥补人类观测资料的不足,是研究气候变化的理想场所。

Fluctuation of closed lake-level and its climatic significance on the middle Kunlun Mountains

Fluctuation of closed-lake level is a highly sensitive indicator for climatic changes.It is verified by lake water equilibrium.Its sensitivity can be expressed in the following equation: Z=A_l/A_b=(P_b-E_b)/(E_l-P_l).Closed lakes in the Middle Kunlun Mountains have undergone three high lake-level stages since 17000a B.P., i.e.around 17000a B.P., 12000a B.P.and 8000-6000a B.P.The first high lake-level stage has relevant to ice melting, shift of westerlies, change of soil humidity and solar radiation.The second stage is relatively stable or a gentle rising again in process of lake shrinking.The third stage ig a result of the global wet and warm climate.Theoretical research and case analysis show that fluctuations of closed lake-level not only can indicate the climatic changes in geological time without meteorological records, but also can meet a deficit of meteorological materials for historical time.Moreover, the Middle Kunlun Mountains is a suitable site-for predicting.