贡嘎山海螺沟冰川物质平衡、水交换特征及其对径流的影响

在贡嗄山海螺沟冰川研究的基础上，提出计算该冰川物质平衡的两种方法，获得了较一致的结果，表明近10a来物质平衡平均为－470mm，与高亚洲边缘山脉的冰种同样处于强烈的衰退状态，该冰川有很高的物质平衡水平（2544mm)及水交换水平（3819mm)，液相比例高（1／3），较小的稳定性系数（0．20），具有典型的季风海洋型冰川的水交换特征，由于冰川退缩冰川径流增加，预计2020年将达到临界状态，在气候持续暖变湿情况下，预测临界状态将延至2050年左右，冰川面积及储量将大幅度减少小。

Mass Balance and Water Exchange of Hailuoguo Glacier in Mount Gongga and Their Influence on Glacial Melt Runoff

Hailuogou Glacier, which lies in an area with largely-varied elevation, is a glacier with rich accumulation, heavy melting and large flow velocity. In the early 1990's, its mass balance was calculated by using different methods, and the results differ remarkably. Since more data were obtained in the last 10 years, it is possible to calculate its mass balance with new methods. Using the ELAo method and the observed melting data obtainel in 19901998, then we get n=－－488 mm. If we use the maximum entropy method and the observed meteorological as well as hydrological data obtained in 1988－1997, then n=－451 mm. These two values are very close and their average value n = －470 mm which is close to the mass balance of the glaciers in the High Asia periphery mountain areas in the last 10 years. Based on the parameters for mass balance, the calculated amplitude of mass balance for Hailuogou Glacier is 2 544 mm, and the water exchange level is 3 819 mm which the liquid water accounts for one third of. this ratio is the high values for glaciers in the High Asia. Meanwhile, the stability cofficient, which is the ratio of the seasonal water exchange amount to the multiple year amount, is low (k = 0. 20). The negative mass balance of the glacier has giver rise to an increase in discharge. It is estimated that the discharge in 2020's will fall back to the original level just before increasing (critical level). The sensitivity analysis on the response of glacier mass balance to meteorological Variations shows that, a 1 K increase of air temperature or a 10 % reduction of precipitation, the responsive values for bn are －214 mm and 354 mm respectively. On the condition that the climate continues getting warmer and more meist, the time at which the discharge reaches to the critical level will proloug to about 2050's. Then the area and volume of the glacier will greatly decrease, which will have great impact on the ecological environment of the upper reach of the Yangtze River.