Glaciological Studies in Asian Highland Regions

1989-1990年在西藏东部和尼泊尔喜马拉雅地区进行了亚洲高原地区的冰川学研究。该项目的目的是研究青藏高原不同气候条件下的冰川特征和冰冻圈在气象水文过程中的作用。野外观测于5 - 6月和9 - 10月在东昆仑山、唐古拉山和牛因坦格鲁拉山进行。在唐古拉山区开展了深入的冰川、气象和水文观测。尼泊尔喜马拉雅地区本项目的一个目的是在朗塘喜马拉雅的水文气象站连续收集数据，该数据自1985年以来一直保持。此外，昆布、邵蓉和朗塘地区的冰川波动持续了十多年。研究的初步结果如下：1。藏东地区主要冰川在一年内的积累是由夏季降水供给的。高原大陆型冰川位于降水少的地区，融水再冻结形成叠加冰对这类干旱地区冰川物质平衡具有重要意义。青藏高原大量降雪的发生，一方面是由于大尺度扰动，另一方面是由于局地强对流。降水的氧同位素组成表明降水可能来自当地的水汽。青藏高原积雪的形成使大气降温，减缓了多年冻土活土层的加深。在雪面上观测到大量的蒸发。自20世纪70年代以来，尼泊尔东部的小冰川一直在后退30-50米，这取决于气温的变化。

Glaciological studies in Asian highland regions in 1989-1990 were made in eastern Tibet and the Nepal Himalaya. Purposes of this project in Tibet were studies of characteristics of glaciers in different climates and the role of the cryosphere in meteorological and hydrological processes on the Tibetan Plateau. Field observations were carried out during the two periods, May-June and September-October, in the East Kunlun Mountains, Tanggula Mountains and Nyaingentanglha Mountains. Intensive observations of glaciology, meteorology and hydrology were carried out in the Tanggula Mountains.A purpose of this project in the Nepal Himalaya was continuous data collection at the hydrological and meteorological station in Langtang Himal which has been maintained since 1985. In addition, glacier fluctuations for over ten years were observed in the Khumbu, Shorong and Langtang regions.Preliminary results of the research are as follows,1. Main accumulation of glaciers in eastern Tibet in a year is supplied with summer precipitation. Continental-type glaciers on the plateau are located in regions with low precipitation, and formation of superimposed ice by refreezing of melt water is important for glacier mass balance in such dry area.2. Abundant snowfall on the Tibetan Plateau occurs partly due to large scale disturbance and partly due to strong local convection. Oxygen isotopes composition of precipitation shows a possibility of precipitation from local origin water vapor.3. Formation of snow cover on the Tibetan Plateau results in cooling of atmosphere and retardation of deepening of the permafrost active layer. Abundant evaporation was observed at the snow surface.4. Small glaciers in east Nepal have been retreating in distance of 30-50m since 1970s depending on air temperature variation.