Title: "Beyond gradual change – Antarctic ice dynamics and tipping points"
Abstract: The Antarctic Ice Sheet is by far the largest potential source of future sea-level change, storing approximately 58m sea-level equivalent. To this day, the complex dynamics of the ice sheet and its surrounding ice shelves are one of the key challenges for sea-level projections. Recent observations show that part of the West Antarctic Ice Sheet is currently retreating, and that this retreat might be irreversible on human timescales. Other regions are protected by so-called ice plugs, hindering the onset of a dynamic instability. Beyond gradual change – Ricarda Winkelmann will discuss the underlying mechanisms and critical thresholds for triggering persistent and possibly rapid ice discharge from Antarctic drainage basins. As a consequence, sea level might continue to rise for centuries or millennia to come. This long-term perspective illustrates that policy decisions made in the next few years to decades will have profound impacts on the global climate, ecosystems and human societies far beyond this century.