Influence of Climate Change on Extratropical Cyclones and Resulting Effects on Arctic Hydrology

The freshwater content of the Arctic Ocean is of concern in climate studies, due to its potential influence on deep water formation in the North Atlantic and, as a result, on global thermohaline circulation. The ultimate short-term source of this freshwater is high latitude precipitation, whether it falls directly into the Arctic Ocean, is delivered as runoff via the Arctic river network, or is carried by interbasin ocean currents. Much of this precipitation is produced during the passage of extratropical cyclones, and changes in the intensity, frequency or preferred locations of these events can lead to critical changes in the spatial and temporal distributions of this precipitation. Using output from version three of the Community Climate System Model (CCSM), a coupled general circulation model, the effects of climate change on the character and frequency of these storms will be discussed and related to changes in source terms of the Arctic Ocean freshwater budget.