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Abstract

The accurate estimations of Greenland ice sheet (GrIS) contribution to sea-level rise require a comprehensive analysis of ice flow dynamic responses to subglacial hydrology, which is currently lacking. Questions arise about how subglacial meltwater affects glacier velocity. The main objective of this study is to observe the influence of the subglacial hydrology system on Kangerlussuup Sermia glacier (Central-West Greenland) velocity through the time series analysis. The previous studies categorized GrIS glaciers into 3 types based on their seasonal velocity changes. However, these studies are still inadequate for a complete understanding of spatial channel distribution. The current study mainly observed the variations in velocity along the glacier flowline of 10km length from the snout position, which are predominantly important to observe the spatial basal hydrology channel distributions and ocean water circulation. We used 13 pairs of Sentinel-1 SAR dataset (from January-2022 to January-2023) and observed the every month velocity changes. The maximum velocity rates are observed during the early summer season due to the increment of subglacial water pressure from the surface meltwater. Later, the deceleration observed from July to August, and the velocity rates are constant during most of the melt season due to the drainage channels becoming more channelized. Although maximum surface velocities observed at the snout (nearly 5.5 m/day), the deceleration rate from July to August is (≈15m in 35 days) is constant throughout 10km profile. Our results reveal that spatial distribution of the drainage pattern is same for the selected profile length of the Kangerlussuup Sermia glacier.