Antarctica ice-sheet loss modeled

The synchronous response of several independent glaciers is generally considered an indicator that the changes are being forced by warming ocean waters. Scientists have documented deep flooding over the Amundsen Sea's continental shelf by almost unmodified Circumpolar Deep Water (CDW); though cold, this deep water is several degrees above freezing and drives rapid melting of the floating terminus of the Pine Island Glacier. To learn more, Thoma et al. model ocean circulation in the Amundsen Sea. They find that influx of CDW is related to regional wind forcing, which can drive seasonal on-shelf flow that varies in strength from year to year. A modeled period of warming following low CDW influx in the late 1980s and early 1990s coincides with a period of observed thinning and acceleration of Pine Island Glacier, suggesting that CDW fluctuations may be driving the observed glaciological changes.-American Geophysical Union