Broadly speaking, glacial isostatic adjustment (GIA) is the study of how the solid Earth and gravity field respond to changes in regional- to global-scale ice mass redistribution. Historically, most GIA studies have focused on the past and on-going response of the Earth to the major, global deglaciation marking the transition from a glacial maximum to the current interglacial between, approximately, 20,000 to 7,000 years ago. The scale and amplitude of ice loss were sufficiently large to produce land motion and gravity changes that remain significant today, and so the GIA signal should be considered when interpretating a variety of global and regional geodetic data sets (e.g., GNSS-based surface motion, GRACE-determined gravity changes). The first part of this presentation will provide some general background on the GIA process and models developed to simulate it. The rest will focus on recent developments and on-going work to improve the accuracy of these models and provide improved uncertainty estimates for end users. Two regional case studies will be used to illustrate some of these developments: eastern North America and Greenland.

Professor Glenn Milne has an honours degree in Geophysics from the University of Edinburgh and an MSc and PhD in Geophysics from the University of Toronto. He has been employed at the University of Ottawa since 2008 and was a Canada Research Chair (Tier II) from 2008-2018. His work has been recognised by the British Geophysical Association, the Geological Society of London, and the American Geophysical Union. He was a Lead Author on the sea-level chapter for the 5th Assessment Report of the IPCC.