Join us for the next BPE Seminar
Constraining Antarctic ice sheet stability during the Last Interglacial
with Joseph Schnaubelt, PhD Candidate in the Computational Climate Change Lab at the University of Connecticut.
Abstract: Our current interglacial climate features an Antarctic ice sheet that has thinned considerably since the Last Glacial Maximum but has remained structural intact through the deglaciation. This may not have been the case during the Last Interglacial (LIG; 130-115 ka) when the ice sheet likely faced a much more substantial retreat from the preceding glacial maximum. According to the IPCC AR6 report, global mean sea level during the LIG was 5 to 10 m higher than present day, requiring significant melt from both the Greenland and Antarctic ice sheets. In fact, a substantially reduced West Antarctic Ice Sheet (WAIS) has been suggested as an explanation for anomalous geochemical signatures observed in Antarctic ice dating to the LIG. To explore this possibility, we will present simulations of the LIG with multiple different WAIS configurations as well as freshwater forcing scenarios to better capture signals recorded in proxy records and the varying climate response to reduced WAIS extent. These simulations use the water isotope-enabled version of the Community Earth System Model (iCESM1.3) to enable the direct comparison between model and ice core water isotope signals. Our results suggest that a substantially reduced WAIS and glacial meltwater in the North Atlantic, likely following Heinrich 11, are together responsible for highly enriched Antarctic water isotopes and warm Southern Ocean temperatures during the LIG. This indicates that the Antarctic ice sheet might be more susceptible to ocean warming than previously thought with the potential to contribute up to 6 m to global mean sea level.
Zoom info:
https://columbiauniversity.zoom.us/j/95332400100?
Meeting ID: 953 3240 0100
Passcode: 504872
Email: Annika Gomez - [email protected]
