Moisture transport into the Arctic: Source‐receptor relationships and the roles of atmospheric circulation and evaporation

Hydrological processes play a key role in the Arctic, as well as being an important part of the response of this region to climate change. The origin of the moisture arriving (and then precipitating) in the Arctic is a crucial question in our understanding of the Arctic hydrological cycle. In an attempt to answer this, the present study uses the Lagrangian diagnosis model FLEXPART (FLEXible PARTicle dispersion model) to localize the main sources of moisture for the Arctic region, to analyze their variability and their contribution to precipitation, and to consider the implications of any changes in the transport of moisture from particular sources within the system. From this analysis, four major moisture sources appear as the most important moisture supplies into the system: the subtropical and southern extratropical Pacific and Atlantic Oceans, North America, and Siberia. Oceanic sources play an important role throughout the year, whereas continental ones only take effect in summer. The sink areas associated with each source have been shown to be moderately influenced by changes in atmospheric circulation, mainly associated with the East Atlantic pattern for the Atlantic source and related to West Pacific and Pacific/North American (PNA) teleconnection patterns for the Pacific one. On the other hand, the variability over the sinks does not seem to be significantly related to changes in evaporation at an interannual scale.