3:30 PM - 4:45 PM
[ACG24-P18] Surface elevation change of outlet glaciers in northwestern Greenland
Keywords:Arctic glaciology, Glacier thinning, Glacier dynamics
In this study, we measured surface elevation change of 14 outlet glaciers near Inglefield Bredning in northwestern Greenland (77°47′–78°10′N, 65°00′–72°47′W). These glaciers flow into the ocean except for two land-terminating glaciers. We processed stereo pair ALOS PRISM images acquired in summer 2007 and 2010 with a digital map plotting instrument (Leica Photogrammetry Suite) to generate DEMs with a 25 m grid mesh. Elevation data from ALOS DEMs were calibrated on ice-free terrain, and compared to calculate ice surface elevation change between 2007 and 2010.
The surface elevation of all the studied glaciers decreased and the magnitude of the elevation change increases downglacier. The mean elevation change rate ranged from −0.4 to −4.9 m a−1. Marine-terminating Tracy and Bowdoin Glaciers thinned at rates of −4.9 and −4.1 m a−1, which were larger than those at other glaciers. The rate at Tugto Glacier, a land-terminating glacier located near Bowdoin Glacier, was −2.8 m a−1. This result confirms that recent thinning of GrIS outlet glaciers is more significant at marine-terminating glaciers as compared to land-terminating glaciers. Rapid thinning of marine-terminating outlet glaciers observed in this study suggests the importance of ice dynamics and/or ice-ocean interaction in the mass loss of GrIS.