Dr Jason Briner - How small did the Greenland Ice Sheet get during the Holocene?

The Greenland Ice Sheet is considered vulnerable to crossing tipping points to complete melting under future climate trajectories of ~3°C above pre-industrial. Knowledge of ice loss during similarly warm past climates, such as the Holocene thermal maximum, could help to improve our understanding of Greenland’s tipping points. It is challenging, however, to reconstruct ice sheets when they were smaller than they are today. This talk summarizes the current state of knowledge of the size of the Greenland Ice Sheet during the Holocene, with particular emphasis on ongoing work (GRATE and GreenDrill projects). The speaker will highlight the leadership across sub-disciplines necessary to yield accurate ice-sheet reconstructions using paleoclimate data time series, field observations of ice-sheet size, solid-earth modeling and numerical ice-sheet simulations. On the path to arriving at a mid-Holocene ice-sheet size estimate are innovations made in an array of scientific methodologies and training of early career scientists, each of which will hopefully pay forward to help mitigate the dire impacts of the climate crisis on future generations.