Comparing Firn Densification Layers Simulated through Regional Climate
Models and those Tracked through Radargrams
The Glacier Energy and Mass Balance (GEMB) module of NASA’s Ice-sheet
and Sea-level System Model (ISSM) can simulate the evolution of firn
density profiles in the ice sheet snowpack. It is a column model that
can give detailed subsurface parameters such as layer depth, snow grain
growth, depth dependent albedo, layer density etc. These parameters are
model simulation outputs, and lack of observations makes them difficult
to evaluate on a broader scale. In this work, we take advantage of
remotely-sensed snow conditions in the top ~15m of the
firn; more specifically, the layer depth vs density profiles, measured
through the Snow Radar sensor from NASA’s Operation IceBridge mission.
We use these observations to calibrate the GEMB module over the
Greenland Ice Sheet. The module optimized with the help of actual
observations will become more reliable for predicting glacial mass loss
and associated global sea level rise over time.