The characteristics of glacier surface velocity in the West Kunlun Mountains derived from ITS_LIVE data from 2000 to 2018
In recent years,the retreat of global glaciers has accelerated in the context of climate warming.How-ever,there is a positive glacier mass balance anomaly in the West Kunlun Mountains of the northwestern Qing-hai-Xizang Plateau.Previous studies found that the mass gain in this region started as early as 1970s,and sever-al glaciers have recently surged.Many large-scale glaciers are concentrated in the main peak area of West Kun-lun Mountains,and the mass balance anomaly of glaciers in the West Kunlun Mountains has attracted extensive attention.However,there many states of the glacier tongue simultaneously,such as advance(normal),shrink-age,stable and surge.The advance and retreat of glaciers are not only related to the mass balance influenced by climate change,but also closely related to the glacier velocity.Previous studies mostly focused on the former,but less on the latter.Therefore,this study uses the ITS_LIVE v01 velocity product,combined with the glacier surface elevation changes and thickness to analyze the characteristics and possible causes of glacier surface veloc-ity change with different states of terminus dynamic in the West Kunlun Mountains from 2000 to 2018,to further understand the glacier motion and velocity changes under the same climate change scenario.The results showed that during the study period,the mean velocity of glaciers in the West Kunlun Mountains was 6.35 m·a-1,and showed a fluctuating upward trend,which was caused by the mass gain caused by the thickening of glacier[(0.15±0.02)m·a-1].The mean velocity of advanced glacier was about 4.07 m·a-1,and showed an increasing trend during the study period,which was resulted by the slight mass gain,the average velocity of retreat glacier was about 4.86 m·a-1,and showed an decreasing trend,this was caused by the mass loss during the period,the mean velocity of stable glacier was 3.04 m·a-1,and the mass balance of this type glacier was basically stable from 2000 to 2018.In the study area,the mean velocity of advanced glacier is smaller than the retreat glacier,because the value of retreat glacier is larger than the advanced glacier.From 2000 to 2018,seven glaciers surged,and the surge period was concentrated in 2010-2015.During the study period,the thickness of the surge-type glaciers increased significantly[(0.35±0.02)m·a-1],resulting in an acceleration in velocity.The re-treat glacier with a large length in the West Kunlun Mountains experienced a surge before 2000 and in a quiet pe-riod now,mass cannot be transported from the upstream to the downstream,leading to the thinning and retreat of the glacier tongue.
West Kunlun Mountainsglacier velocityglacier thicknessglacier surface elevation changesurge-type glacier
NETL
NSTL
万方数据
