Characteristics Of Glacier Movement In The Eastern Pamir Plateau

Under the background of global warming,most glaciers are in retreat,but a few are in stable or advancing state,especially in the Pamir and Karakoram Mountains,which is called the"Pamir-Karakoram Anomaly".Glacier movement controls the ice transport and provide important information for glacier variation,mass balance and so on.To deepen the glacier change the understanding of the differences in mechanism,take the eastern Pamir Plateau as an example,this paper using Landsat series of remote sensing data from 1989 to 2020,ITS_LIVE,Sentinel 1A data from 2015-2016 and so on for a long time series of glacier velocity,to system analyzes the changes in the rate of glacial movement in the spatial area and the reasons of spatio-temporal changing,and discusses the glacier movement speed change and the relationship between the material balance changes,provide "pamir-karakoram abnormal" new research perspective.The main research contents and conclusions of this paper are summarized as follows:(1)COSI-Corr method was used to analyze the effects of different bands,different matching windows and different time intervals on glacier velocity extraction based on Landsat TM images.The results showed that:when the initial window and the termination window were set as 128 and 64,the error of off-glacier area was the minimum.The accuracy of glacier velocity is the highest when the time interval is 336 days and 32 days.(2)The average velocity of 61 glaciers in the Muztag-Kongur region during 2013-2020 was selected to explore the spatial distribution characteristics of glacier movement velocity in combination with glacier area,aspect,slope,median altitude,length,and coverage rate of debrise.The results show that the velocity of glacier movement in the western aspect is higher than that in other slope directions,and the velocity of glacier movement in the western aspect is significantly different(0.03 m·d-1),which may be influenced by the westerly circulation.Glacier size(area,length)is moderately correlated with glacier velocity.The glacier movement mechanism in the eastern Pamir may be dominated by both base sliding and glacial ice deformation.(3)Based on Landsat remote sensing data and ITS_LIVE data,the annual glacial velocity data of the Eastern Pamir Plateau were obtained from 1990 to 2020 with long time series.The results show that from 1989/1990 to 2000,the glacier velocity in the south of Muztag and Kungey Mountain is accelerated,the glacier velocity in KongurMountain slowed down,and the glacier velocity in the north of Kungey Mountain was stable.From 2000 to 2012,the glacier velocity in the Muztag,Kongur and the south of Kungey Mountain accelerated slightly,while the north of Kungey Mountain slowed down.From 2013 to 2020,the glacier velocity in Muztag,Kongur and Kungey Mountain increased rapidly.Glacier mass balance in the eastern Pamir Plateau is in the mass balance transition zone from positive to negative.Glacier mass balance in the north and south Kungey Mountains is negative(-0.007± 0.001m w.e.a-1 and-0.03 5± 0.002 m w.e a-1),and glacier mass balance in Kongur and Muztag is positive(0.157±0.011 m w.e.a-1 and 0.294±0.021 m w.e.a-1),which is affected by the increasing westerly circulation.The movement of the Karayaylak Glacier in 2015 is controlled by thermodynamic mechanisms.Figure[29]table[15]reference[120]...