Abstract
The rate of land ice loss due to iceberg calving is a key source of
variability among model projections of 21st century sea level rise. In
Greenland, where ice drains to the ocean through hundreds of outlet
glaciers, it has been especially challenging to account for iceberg
calving from glaciers smaller than typical model grid scale. Here, we
apply an efficient, physically-based network flowline model (SERMeQ)
forced by surface mass balance to simulate decadal terminus position
change of 155 grounded outlet glaciers of the Greenland Ice
Sheet—resolving five times as many outlets as was previously possible.
We compare these simulations with observed changes in terminus position
and find that SERMeQ produces generally realistic rates of retreat.
Moreover, SERMeQ is designed to overestimate retreat and can be used to
provide an upper bound on forward projections of the dynamic mass loss
from the Greenland Ice Sheet associated with different climate
projections.