Antarctica is losing more ice than ever, scientists reported in 2015. Its ice shelves — the thick, floating slabs that encircle the continent — are taking the biggest hit. The shelves slow and stabilize the glaciers behind them, but they are succumbing to a hidden force: Deep, warming ocean currents are melting the ice from beneath.
The collapse of several small ice shelves has caused glaciers to accelerate two- to ninefold and spill more ice into the ocean, raising the sea level. A study published in April shows that more ice shelves are coming into play: From 1994 to 2012, the rate of ice shelf shrinkage increased twelvefold. Parts of the ice sheet considered at risk hold enough ice to raise the global sea level by 22 feet. Here’s how our understanding of Antarctica’s vulnerability advanced in 2015.
