Hydrological and Kinematic Precursors of the 2017 Calving Event at the Petermann Glacier in Greenland Observed from Multi-Source Remote Sensing Data

Both a decrease of sea ice and an increase surface meltwater, which may induce ice-flow speedup frontal collapse, have significant impact on the stability floating shelf in Greenland. However, detailed dynamic precursors drivers prior to fast-calving process remain unclear due sparse remote sensing observations. Here, we present comprehensive investigation hydrological kinematic before calving event 26 July 2017 Petermann Glacier northern Greenland, by jointly using observations at high-temporal resolution model. Time series velocity fields during were retrieved with Sentinel-2 sub-weekly sampling interval. The speed quickly reached 30 m/d (the day calving), is roughly 10 times quicker than mean glacier velocity. Additionally, radar backscatter coefficient Sentinel-1 images suggests rapid transformation from landfast into open water, associated extent. area melt ponds tongue began mid-May, peak end June lasted for nearly one month until occurred. We used sheet system model spatial-temporal damage stress ice, thereby finding abnormal distribution cracked region. It inferred that this relate weakening shearing tributary glacier, meltwater infiltrating crevasses.