Late Pleistocene Glaciation In Helan Mountain And The Relationship Between The Evolvement Of The Monsoon

Glacier is a natural phenomenon, studies the process of this phenomenon and its interaction with other pacts is an integral part of the natural sciences. Glacier as a valuable water resources, makes an important role on agriculture and industrial development of the west of China, and glaciers contain many information on climate and environmental change, during the study of the former glacier, we could find out the cause of the ancient climate change, and predict the future trend of the climate change.In this paper, Helan Mountain as research region, located in the eastern edge of Qinghai-Tibet Plateau, study the paleoglaciation of Helan Mountain has a great significance of science to the ancient climate change of the inner zone of China. Use the methods that sampling in the field, sediment analyzing in the lab, and analyzing the sediment characteristics of glacial geomorphology, ascertain the glacial evolution process and so on.Helan Mountain preserves the late Quaternary glacial remains, which distribute on the summit area above 2800m a.s.l., and the typical glacial morphology exists in Chagou region. The glaciation was proceeding at the Last Glacial Maximum (LGM). According to the relationship between the summer, June, July and August the annual precipitation and the atmospheric temperature at the equilibrium line altitude, the present ELA in Helan Mountain was 4724±100m. And the altitude of cirque floor, the terminal to summit altitudinal, the terminal to average elevation of the catchment area and the accumulation area ratio were used for calculation of the former ELAs . These methods provided the equilibrium line altitude for an average altitude of 3101m during the LGM.The climate of Helan Mountain is mainly on the impact of the East Asia monsoon system. Because of the block of the Taihang Mountain, Liupan Mountain and Qinling, the humid warm air comes from the southwest Pacific has been weak just bring a little rainfalls. And in winter, the big and powerful Mongolia-Siberia high pressure cell produced a strong northwest wind, so Helan Mountain is mainly affected by the impact of winter monsoon. The development and changes of the winter monsoon make a key action of the landscape of the Helan Mountain.