A sensitivity study of annual area change for Greenland ice sheet marine terminating outlet glaciers: 1999-2013
Trine S. Jensen[1,2], Jason E. Box[2] and Christine S. Hvidberg[1]
[1] Center for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark.
[2] Geological Survey of Denmark and Greenland, Copenhagen, Denmark.
ABSTRACT. The mass flux from marine terminating glacier outlets from the Greenland ice sheet is a significant mass budget term. Yet, glacier calving sensitivity to climate parameters is not well understood. In this study, the front area changes of 42 marine terminating Greenland outlet glaciers are measured annually from 1999 to 2013 using optical satellite imagery. 35 glaciers retreated while 7 remained stable. The average front position change was -240 m a−1 and the total rate of front area change was -114 km2 a−1. The yearly average area changes of all measured glaciers are compared with interannual variations in SST, Sea Ice Concentration (SIC), surface melt, Northern Hemisphere (NH) surface air temperatures and the North Atlantic Oscillation (NAO) index. We find: 1) northwestern glacier area change have a significant correlation with surface melt and NH land temperature variations; 2) southeastern glaciers have a significant correlation with local SST, SIC and NH temperatures; and 3) southwestern glacier area change correlates significantly with local SST and NAO index. We conclude that a climate sensitivity signal emerges considering a population of glaciers. Further, we find a significant correlation between the date of minimum extent and glacier latitude. Area change data are available from https://GAC.geus.dk
citation:
Jensen, T. J.E. Box, and Christine Hvidberg, 2016. A sensitivity study of yearly Greenland ice sheet marine terminating outlet glacier changes: 1999-2013, Journal of Glaciology, 15J085