Heat Sources within the Greenland Ice Sheet: Dissipation, Temperate Paleo-Firn and Cryo-Hydrologic Warming

Ice temperature profiles from the Greenland Ice Sheet contain information on the deformation history, past climates and recent warming. We present full-depth temperature profiles from two drill sites on a flow line passing through Swiss Camp, West Greenland. Numerical modeling reveals that ice temperatures are considerably higher than would be expected from heat diffusion and dissipation alone. The possible causes for this extra heat are evaluated using a Lagrangian heat flow model. The model results reveal that the observations can be explained with a combination of different processes: enhanced dissipation (strain heating) in ice-age ice, temperate paleo-firn, and cryo-hydrologic warming in deep crevasses.Swiss National Science Foundation 200021_127197US-NSF OPP 0908156, OPP 0909454, ANT-0424589NASA within the US Department of Energy Office of ScienceGeological Science