A comparative study on mass balance between the continental glaciers and the temperate glaciers: Taking the typical glaciers in the Tianshan Mountains and the Alps as examples
Under the background of global warming,most of glaciers retreat all over the world. According to the water-thermal environment that glaciers developed in,as well as glacier physical properties,continental glaciers and temperate glaciers can be classified out. The two type glaciers exist significant differences in degree,process and mechanism in respond to climate change. So it is of great significance to conduct the comparative study on mass balance characteristics and mechanisms in respond to climate change between the two type glaciers. In this paper,the Glacier No. 1 at the headwaters of therumqi River and Tuyuksu Glacier,respectively in east and west Tianshan Mountains,and Hintereisferner Glacier,Careser Glacier and Sarennes Glacier in the eastern, central and western Alps,respectively,are taken as sample glaciers. The characteristics and mechanisms of the mass balance change are compared for the two glacier types. Based on a comparative analysis on the differences in amplitude of fluctuation and phasic change of the mass balance during the 60 years. The results show that the temperate glaciers have greater amplitude of fluctuation than that of the continental glaciers due to their differences in water-thermal environment and in sensitivity to climate change. Phasic change of mass balance was similar in the Alps,but was much different not only between the glaciers in the Tianshan Mountains and the Alps, but also between the two glaciers in the Tianshan Mountains. This indicates that the difference not only exist between different property glaciers but also among the same type glaciers. In addition,on the basis of predecessors' research on glacial retreat mechanisms,the similarities and differences in mechanisms of glacier mass balance between the continental glaciers and the temperate glaciers also studied. The air temperature rising during ablation season and the glacier surface albedo reduction are considered responsible for the accelerated ablation not only for the continental glaciers but also for the temperate glaciers. Moreover,the ice temperature rising and the glacier fragmentation are another important mechanism for speeding up ablation of the continental glaciers and the temperate glaciers.