基于RS与GIS的冰川变化研究——青藏高原北侧新青峰与马兰冰帽变化的再评估  

Variation of Glaciers Studied on the Basis of RS and GIS-A Reassessment of the Changes of the Xinqingfeng and Malan Ice Caps in the Northern Tibetan Plateau

作　　者：刘时银[1] 上官冬辉[1] 丁永建[1] 韩海东[1] 张勇[1] 王建[1] 谢昌卫[1] 丁良福[1] 李刚[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所冰芯与寒区环境重点实验室

出　　处：《冰川冻土》2004年第3期244-252,共9页Journal of Glaciology and Geocryology

基　　金：中国科学院知识创新工程重大项目(KZCX1 10 06);国家自然科学基金重大项目(90202013);国家自然科学基金优秀创新群体项目(40121101)资助

摘　　要：应用遥感(RS)与地理信息系统(GIS)技术,分析了位于青藏高原东北部,可可西里地区、昆仑山脉中段的新青峰和马兰冰帽近30a来的冰川变化.1971—2000年间新青峰冰帽总面积呈减小变化,马兰冰帽面积有所增加;结合以往研究结果,发现新青峰冰帽面积变化在1979年前后为突变点,1979年前冰帽总体面积扩大,之后面积迅速减小,期间经历了1989—1994年相对稳定的时期.进一步分析新青峰冰帽东南侧新青峰冰川和西北侧西新青峰冰川长度变化过程,发现新青峰冰帽面积变化在很大程度上取决于这两条冰川的变化.研究时段内两条冰川末端进退变化有较大差异,西新青峰冰川在1971—1976和1994年之后为退缩期,1976—1994年间为前进,而新青峰冰川则有所不同,该冰川1971年以来一直处于退缩之中,但不同时段退缩速率不同,且1994年后有加速退缩的趋势.根据马兰冰帽冰芯δ18O记录所反映的夏季气温变化,近50a来研究区在1976年之前为相对高温期,之后为相对低温期,两冰川不同的长度变化趋势可能与两冰川对气候变化具有不同的动力响应特征有关.根据两条冰川冰面地形特征分析认为,受地形条件制约,两条冰川可能具有不同的冰川表面物质平衡梯度,这也可能是两冰川具有不同的动力响应特征的影响要素之一.By applying remote sensing (RS) and geographical information system (GIS) techniques, an analysis of glacier changes during the last 30 year was made for Xinqingfeng and Malan Ice Caps, located at the central part of the Kunlun Mountains to the northern Tibetan Plateau. To this purpose, 1∶100000 topographical maps, aerial photos, Landsat MSS and TM that were co-registered to map coordinate are used. Results indicate that the Xinqingfeng Ice Cap has experienced a general shrinkage and on the contrary the Malan Ice Cap just to the south of the former one has seen an increment in area from 1971 to 2000. Compared with previous study, it is found that the Xinqingfeng Ice Cap had an abrupt change in 1979. Before 1979 the area of the ice cap increased and after 1979 the ice cap retreated, with a relatively steady state during 1989_1994. As a matter of fact, area change of the Xinqingfeng Ice Cap was controlled to some extent by the variation of the Xinqingfeng Glacier in the southeast side of the ice cap and the West Xinqingfeng Glacier in the northwest side of the ice cap, the first and second largest glaciers around the Xinqingfeng Ice Cap. These two glaciers have experienced different variation patterns during the research period; the Xinqingfeng Glacier has been retreating all the time since 1971 with an accelerating trend after 1994, while the West Xinqingfeng Glacier retreated during 1971_1976 and after 1994 and advanced obviously during 1976_1994. Variation of (δ^(18)O), a good proxy of air temperature, recorded in the upper section of the Malan ice core reveals a warm period during 1950_1976, with mean temperature about 0'5 ℃ higher than that after 1976. The distinct terminus variations of the two glaciers could be attributed to different responses of the two glaciers to climatic change. The discrepancy in dynamic response may be controlled by different surface mass-balance gradients, which can be inferred from area-altitude profile and surface slopes of the two glaciers. In summary, no obvious climate-warm

关 键 词：新青峰冰帽 冰川变化 遥感与地理信息系统 

分 类 号：P343.6[天文地球—水文科学]