Current Research in EEPS: Dr. Jaqueline Austermann, Lamont-Doherty Earth Observatory, Columbia University
The Last interglacial (~125ka) was 0.5-1.5 ºC warmer than today, making it an interesting natural experiment for how ice sheets respond to modest warming. In this talk I will first describe past estimates for Last interglacial sea level and corresponding polar ice retreat before presenting our new assessment from sea level data in the Bahamas. I will show our field evidence and describe how we can leverage the spatial extent of the data to constrain the contribution of glacial isostatic adjustment to past sea level. Based on these data, we find that Last Interglacial sea level very unlikely exceeded ~5m, which is below the current estimate from the IPCC. Next, I will present new Last Interglacial sea level data from northwest Europe, and argue that these observations predominantly constrain the contribution from the Antarctic ice sheet during the Last interglacial. Combining both results (from the Bahamas and northwest Europe) allows us to not only produce a new time-varying estimate of Last Interglacial sea level, but also partition this melt between Greenland and the Antarctic ice sheets. I will end by speculating what these new results mean for future sea level rise under different emission scenarios.
