The overall aim is to establish the timing and rate of thinning of the West Antarctic Ice Sheet (WAIS) from its maximum extent in an area inland of the Weddell Sea embayment. The specific objectives are (a) to date geomorphological evidence of ice sheet thinning in the Ellsworth Mountains using in situ cosmomogenic nuclides and (b) to infer WAIS dynamics (specifically grounding line and ice volume changes) in the Weddell Sea embayment through high-resolution glaciological modelling, constrained against the geomorphological record of elevation change through time. The importance of the project is that the past dynamics of the WAIS have implications for its future behaviour, and thus global sea level change.