Constraining the mass balance of East Antarctica

In every experiment, mass loss from the west always exceeded gains in the east.

Jonathan Bamber, lead author of the study

• Investigates the mass balance of East Antarctica for the period 2003–2013 using a Bayesian statistical framework
• Combines satellite altimetry, gravimetry, and GPS with prior assumptions characterizing the underlying geophysical processes
• Runs three experiments based on two different assumptions to study possible solutions to the mass balance
• Solves for trends in surface mass balance, ice dynamics, and glacial isostatic adjustment
• The first assumption assigns low probability to ice dynamic mass loss in regions of slow flow, giving a mean dynamic trend of 17 ± 10 Gt yr−1 and a total mass imbalance of 57 ± 20 Gt yr−1
• The second assumption considers a long-term dynamic thickening hypothesis and an a priori solution for surface mass balance from a regional climate model
• The latter results in estimates 3 to 5 times larger for the ice dynamic trends but similar total mass imbalance
• In both cases, gains in East Antarctica are smaller than losses in West Antarctica