The large-scale freshwater cycle of the Arctic
Article first published online: 21 NOV 2006
Copyright 2006 by the American Geophysical Union.
Journal of Geophysical Research: Oceans (1978–2012)
Volume 111, Issue C11, November 2006
How to Cite
2006), The large-scale freshwater cycle of the Arctic, J. Geophys. Res., 111, C11010, doi:10.1029/2005JC003424., , , , , , , , , and (
- Issue published online: 21 NOV 2006
- Article first published online: 21 NOV 2006
- Manuscript Accepted: 18 JUL 2006
- Manuscript Revised: 9 MAY 2006
- Manuscript Received: 1 DEC 2005
- freshwater budget
 This paper synthesizes our understanding of the Arctic's large-scale freshwater cycle. It combines terrestrial and oceanic observations with insights gained from the ERA-40 reanalysis and land surface and ice-ocean models. Annual mean freshwater input to the Arctic Ocean is dominated by river discharge (38%), inflow through Bering Strait (30%), and net precipitation (24%). Total freshwater export from the Arctic Ocean to the North Atlantic is dominated by transports through the Canadian Arctic Archipelago (35%) and via Fram Strait as liquid (26%) and sea ice (25%). All terms are computed relative to a reference salinity of 34.8. Compared to earlier estimates, our budget features larger import of freshwater through Bering Strait and larger liquid phase export through Fram Strait. While there is no reason to expect a steady state, error analysis indicates that the difference between annual mean oceanic inflows and outflows (∼8% of the total inflow) is indistinguishable from zero. Freshwater in the Arctic Ocean has a mean residence time of about a decade. This is understood in that annual freshwater input, while large (∼8500 km3), is an order of magnitude smaller than oceanic freshwater storage of ∼84,000 km3. Freshwater in the atmosphere, as water vapor, has a residence time of about a week. Seasonality in Arctic Ocean freshwater storage is nevertheless highly uncertain, reflecting both sparse hydrographic data and insufficient information on sea ice volume. Uncertainties mask seasonal storage changes forced by freshwater fluxes. Of flux terms with sufficient data for analysis, Fram Strait ice outflow shows the largest interannual variability.