Modeling ice sheet change in Antarctica
Modeling efforts provide new data on the effects of climate change in Antarctica.
Between 1998 and 2016, warming in Antarctica has been rapid and significant. Recent observations also reveal increases in snowfall in western Queen Maud Land, East Antarctica that are unprecedented over the past two millennia. To investigate these changes, a team of NSF-sponsored researchers and NASA scientists merged observation-based NSF-funded research with global modeling efforts that benefited from NASA satellite and airborne-based data[1]. Researchers determined that models were underestimating snow accumulation and temperature increases in this region, with implications for sea level rise estimates based on contributions from the East Antarctic Ice Sheet. Updated climate model projections suggest that additional snowfall over Antarctica, largely due to atmospheric warming, is expected to partly offset dynamic ice losses by the end of the 21st century[2]. However, even small variations in the modeled snowfall accumulation rates created great uncertainty about the balance of ice loss and accumulation in Antarctica. The mitigating impact of higher snowfall rates is therefore not fully resolved, indicating a need for improved evaluation of global atmospheric model performance in Antarctica.
1 Medley, B., J.R. McConnell, T.A. Neumann, C.H. Reijmer, N. Chellman, M. Sigl, S. Kipfstuhl, 2017. Temperature and snowfall in western Queen Maud Land increasing faster than climate model projections. Geophysical Research Letters, https://10.1002/2017/GL075992
2 Ibid.
Left: In the study area in Queen Maud Land, eastern Antarctica, the blue area experienced increased snowfall related to warming temperatures[1]. Right: Until recently, annual snowfall, as recorded in the historical ice core record (blue), remained within preindustrial averages (dashed grey lines). Data modeled by the Community Earth System Model includes an artificially-controlled run (green) and an ensemble data run (red), showing the potential projected snowfall increases based on the NSF data recorded at Queen Maud Land. The grey area around the ensemble data is the margin for error. Source: NASA.
1 Ibid.