Antarctica unplugged – climate change, ice dynamics and sea-level rise

Ricarda Winkelmann Colder, windier, drier than anywhere else on the
globe - Antarctica is a continent of superlatives. It is covered by
a massive ice-sheet, storing water equivalent to more than 50
meters of global sea-level rise. The ice is constantly moving,
flowing from the continent’s interior towards the ocean - forming,
melting, re-freezing, breaking. To this day, these complex dynamics
of the Antarctic Ice Sheet are the key challenge for projections of
future sea-level rise under climate change. Recent observations
show that part of the West Antarctic Ice Sheet is rapidly
retreating, and that this retreat is likely irreversible on human
timescales. Other regions are currently protected by so-called ice
plugs, small volumes of ice which hinder the onset of a dynamic
instability. However, man-made climate change increases the risk of
triggering persistent ice discharge from the adjacent basins into
the ocean. We will review the processes behind these dynamic
(in)stabilities and explore the implications for future sea-level
rise. Burning all of the world’s available fossil-fuel resources
could eventually result in the complete melting of the Antarctic
Ice Sheet and cause long-term global sea-level rise unprecedented
in human history.