C22B-07
First synchronous realistic simulations of Antarctic and Greenland SMB in a fully coupled climate model
Tuesday, 15 December 2015: 11:50
3007 (Moscone West)
Jan Lenaerts1, Leo van Kampenhout1, William H Lipscomb2, Andrew Gettelman3, Michiel van den Broeke4, William Sacks3, Jeremy Garmeson Fyke2, Miren Vizcaino5 and Marcus Löfverström3, (1)Utrecht University, Utrecht, Netherlands, (2)Los Alamos National Laboratory, Los Alamos, NM, United States, (3)National Center for Atmospheric Research, Boulder, CO, United States, (4)University of Oregon, Eugene, OR, United States, (5)Delft University of Technology, Delft, Netherlands
Abstract:
Here we use the global, coupled ocean-atmosphere-land Community Earth System Model (CESM) at a 1o degree horizontal resolution to simulate recent past (1850-now) and future (21st century) Greenland and Antarctic ice sheet SMB in tandem. To that end, we have recently improved the representation of firn in CESM. We increased the vertical thickness of snow, which enhances the buffering of meltwater through refreezing, and firn density, to allow for wind-induced snow compaction. Other model improvements focused on atmospheric clouds; the most recent CESM atmosphere model allows for more liquid water in clouds, which increases positive longwave cloud forcing, and has profound and beneficial impact on the ice sheet surface radiation balance. In this contribution, we will show that the above improvements enable a realistic CESM simulation of both Greenland and Antarctic SMB. This allows for analysis of future evolution of ice sheet SMB and the interactions between ice sheets and other components of the climate system.
