Arctic Freshwater Export: Status, Mechanisms, and Prospects

Dr. Thomas Haine, Johns Hopkins University

Large freshwater anomalies clearly exist in the Arctic Ocean. For example, liquid freshwater has accumulated in the Beaufort Gyre in the decade of the 2000s compared to 1980–2000, with an extra ? 5000 km3 (about 25%) being stored. Both the sources of freshwater and the Arctic surface wind are important controls on freshwater anomalies, and both have changed in the last decade. Coupled climate models project continued freshening of the Arctic during the 21st century, with a total gain of about 50000 km3 for the Arctic, CAA, and Baffin Bay (an increase of about 50%) by 2100. Rapid discharges of excess freshwater through Fram or Davis straits appear possible, triggered by the wind, but are hard to predict. This talk will describe recent changes in the Arctic Ocean freshwater system, review attempts to understand the mechanisms causing these changes, and speculate about future prospects, especially for the oceanic export of Arctic freshwater.