Briefing: Antarctic ice sheet mass loss and future sea-level rise

Sea-level rise, one of the most obvious consequences of climate change, has direct impacts on coastal communities and economic infrastructure. It is important to assess current sea-level rise and forecast future rates. These predictions are made difficult because the potential for rapid destabilisation of some of the world's large ice sheets, in particular the west Antarctic ice sheet, remains poorly constrained. In particular, new processes and new mapping and modelling, currently emerging from the science community, may have a radical impact on forecasts. Here, a summary of observations and models of recent west Antarctic ice sheet dynamics are provided. This summary highlights that sea-level rise above the ∼1 m expected by 2100 is possible if ice sheet response begins to exceed present rates. Moreover, ice losses from Antarctica have an amplified impact on the coastlines of North America and Europe, because of the resulting redistribution of water due to the changed gravitational field near the ice sheet.