Ice Surface-Elevation Changes of Glacier No.4 of Sigong River in Bogda, Tianshan Mountains
详细信息
- 责任者：Wang Puyu (College of Geography and Environment Science ; Northwest Normal University ; Lanzhou 730070 ; China) ; Li Zhongqin
- 刊名：Arid Land Geography
- 出版年：2011
- 卷期：34(3)
- 关键词：大陆冰川 ; continental glacier ; 天山 ; Tianshan Mountains
- 页码：p.464-470
- 图表：illus., 1 table, 32 refs.
- 分类号：1800
- issnNo：ISSN1000-6060
- isbnNo：CN65-1103/X
摘要
Mountain glaciers are important water resources in the arid region and their mass loss or accumulation directly influence the water runoff.In addition,glaciers are one of potential climate indicators because they are sensitive to climate changes.Bogda is the biggest glaciation area in the eastern Tianshan Mountains and the glacier changes in this region directly influence water resources,living environment and other aspects,which have attracted wide attention of many researchers at home and abroad.Therefore,in the context of global warming,it is urgent to study the glacier changes in this region.In 2009,a large-scale scientific expedition was taken in Bogeda by staffs of Tianshan Glaciological Station and Glacier No.4 of the Sigong River was measured by high accuracy Real Time Kinematic-Global Position System(RTK-GPS).In this paper,ice surface-elevation changes of Glacier No.4 of the Sigong River from 1962 to 2009 had were studied by comparing the DEMs in the two periods,which were established from the GPS surveying data in 2009 and the topographic map(1∶50 000) in 1962,respectively.The study of ice surface-elevation changes can be used to estimate the mass loss or accumulation by calculating changes in ice thickness and ice volume,which is an effective method to estimate mass balance of glaciers lack of long-term observations,supplying reliable data for the evaluation of water resources accordingly.Moreover,ice surface-elevation changes within different ranges of elevation and slope were also analyzed in detail.Results indicated that the ice surface-elevation of the tongue area was decreased by 15±10 m with a rate of 0.32±0.2 m·a-1 during 1962-2009.It can be calculated that the wasting ice volume caused by the glacier thinning reaches to(14.3±9.5)×10-3 km3,corresponding to(12.9±8.6)×10-3 km3 water equivalent.That is to say,Glacier No.4 of the Sigong River supplied water runoff of(12.9±8.6)×10-3 km3 at least in the past 50 years.Analysis shows that there is considerable variability of ice surface-elevation changes within different range of elevation and slope.The changes of ice surface-elevation are especially intense at low elevations and on small slopes.During the past several decades,due to climatic warming,Glacier No.4 of the Sigong River was in the state of rapid thinning,retreating,shrinkage and ice volume wasting,which obviously represents that glaciers in Bogda are experiencing serious mass losses and will make a direct impact on water resources.