Antarctica’s Pine Island Glacier is preparing to shed a 300-square-mile chunk of its ice to the ocean in a process of ice loss that has been accelerating in recent years, reports Pette Spotts at the Christian Science Monitor. Although modest by historical standards, the Pine Island Glacier’s losses probably represent Antarctica’s largest contribution so far to global sea-level rise, notes Hamish Prichard, a researcher with the British Antarctic Survey. The glacier is a key outlet for the West Antarctic Ice Sheet, one of the continent’s two major ice caps and a significant source of concern for long-term sea-level rise as the globe’s climate warms, mostly from burning fossil fuels. Glaciologists suspect that relatively warm ocean water – so-called circumpolar deep water – is melting the underside of the ice shelf. A recent published study in the journal Nature Geoscience projected that even if carbon dioxide emissions end by 2100, stabilizing global average temperatures, the warming will have set up long-term oceanic circulation changes that will continue to warm Antarctic waters for thousands of years, collapsing the West Antarctic Ice Sheet and raising sea levels by several meters.
Huge chunk of Antarctic ice sheet set to break free. A 300-square-mile portion of the Pine Island Glacier is expected to break off in the next few months, creating a massive Antarctic iceberg. The glacier is contributing the sea-level rise. Christian Science Monitor