Aurora Basin, the weak underbelly of East Antarctica

The East Antarctic Ice Sheet (EAIS) has the potential to raise global sea levels by ∼52 m. Here, we model the evolution of select EAIS catchments to 2100 using three basal melt rate parameterizations and force our model with surface mass balance and ocean thermal anomalies from 10 global climate models. While the domain loses mass under low‐emission scenarios, it gains ∼10‐mm sea‐level rise equivalent ice volume (SLRe) under high‐emission scenarios. The primary region of thinning is within 50 km upstream of Totten Glacier's grounding line. Totten's glacial discharge is modulated by the migration of its grounding line, which is sensitive to brief intrusions of ocean water at temperatures higher than present. Once the grounding line is dislodged, Totten's ice velocity increases by up to 70% of present‐day values, resulting in ∼6‐mm SLRe loss from this sector.