Analytical study on glacial and glacial lake variations : comparison between in the Monsoon Asia and Arid Asia

点击翻译按钮获取中文摘要

1. Interpretation and mapping from aerial photographs, satellite images, and maps were carried out, and information on the main topics were collected in Mongolia and India.2. Based on these materials and data, glacial variations, glacial lake expansions, and climate changes were analyzed.3. Monsoon Asian regions: Frontal variations of glaciers in the Lahul Himalayas, India during the recent 50 years were measured by analyzing of satellite images and field data. The results show that many glaciers are retreating. GLOF (glacial lake outburst flood) events have been common phenomena in the high mountain areas of the eastern Himalayas (especially in Bhutan) in the past 50 years, and have been accelerated in the recent years. We cautioned the risks of GLOFs in the areas.4. Arid Asian regions: In the eastern Tienshan Mountains, many glaciers have retreated and several small ones have already disappeared. In the northern Karakorum, Pakistan, small glaciers became small in size, while many sev … More eral large glaciers without debris mantles have increased in their volume. In the mountains of Mongolian Altai (western Mongolia), areal changes of glaciers between 1940 and 2000 were mapped from air-photo based maps and Landsat 7EWTM+. Glacial areas decreased 10-30%,between 1940 and 1980, and no clear change has occurred after 1980.5. Climatic change: Fluctuations of air temperature, precipitation, and snow depth in Mongolia between 1960-2001 indicate that cold and much snow climate prevails from the 1960s to 1970s, but warm and less snow climate appeared in the 1990s. Basic data of Global Historical Climatology Network in the piedmont areas around the Tienshan Mountains, Central Asia, were corrected and checked the quality of the data with hydrological data.6. Conclusions: Investigation by satellite images indicate that the changing trends of glaciers and glacial lakes are different between in the Monsoon Asia and Arid Asia, and the corresponding climates are exist in Asian Continent. Less