Ice-sheet losses track high-end sea-level rise projections

Comparing the IMBIE assessments of Greenland and Antarctica mass change to the IPCC Fifth Assessment Report (AR5) sea-level predictions shows that observed ice-sheet losses track the upper range of the sea-level predictions during their 10-year overlap (2007-2017). These upper-estimates predict an additional 17.9 mm of sea-level rise from the ice sheets above the central predictions by 2100, which would put 50 million people at risk of coastal flooding. This comparison also shows that the high inter-annual variability in Greenland surface mass balance and in Antarctica dynamic ice losses are not reproduced in AR5, and that ice-sheet models must account for this short-term variability in order to accurately predict sea-level rise.