Greenland Ice Sheet Contribution to 21st Century Sea Level Rise as
Simulated by the Coupled CESM2.1-CISM2.1
Abstract
The Greenland Ice Sheet (GrIS) mass balance is examined with an Earth
system/ice sheet model that interactively couples the GrIS to the land
and atmosphere.
The simulation runs from 1850 to 2100, with historical and SSP5-8.5
forcing. By mid-21st century, the cumulative contribution to global mean
sea level rise (SLR) is 23 mm.
Over the second half of the 21st century, the surface mass balance
becomes negative in all drainage basins, and an additional 86 mm of SLR
is contributed.
The annual mean GrIS mass loss in the last two decades is 2.7 mm sea
level equivalent (SLE) yr-1. Strong decrease in SMB (3.1 mm SLE yr-1) is
counteracted by a reduction in ice discharge from thinning and retreat
of outlet glaciers.
The southern GrIS drainage basins contribute 73% of the mass loss by
mid-century. This decreases to 55% by 2100, as surface runoff in the
northern basins strongly increases.