Freshwater Fluxes into the World Oceans (GRDC, 2009) - online only
Recommended citation: Couet, Thomas de and Thomas Maurer (2009):Surface Freshwater Fluxes into the World Oceans / Thomas de Couet; Thomas Maurer. Global Runoff Data Centre. Koblenz: Federal Institute of Hydrology (BfG), 2009.
Freshwater input from continents into the oceans is of major interest in research concerned with global monitoring of freshwater resources, the flux of matter into coastal areas and the sea, or the influence of freshwater fluxes on circulation patterns. GRDC calculated the mean annual Surface Freshwater Fluxes into the World Oceans
on the basis of a 0.5° source grid optimised for flow path detection. By application of GIS analysis procedures, the specific catchments of 12.000 individual grid cells that form the fringe of the continents were determined so much as all adjacent continental grid cells were co-registered with their respective fringe grid cell through which they drain to the oceans.
For the calculation of the fluxes we used the mean river discharges calculated with WaterGAP 2.1 by a team at the University of Frankfurt, Germany (Hunger, M., Döll, P. (2008): Value of river discharge data for global- scale hydrological modeling. Hydrol. Earth Syst. Sci., 12, 841-861, 2008.). In the result, a GIS compatible table of 0.5° continental coastline cells comprises the catchment-related mean annual runoff volume in cubic kilometre. A comparison with other previous estimates is given in the table below.
Freshwater Fluxes into the World Oceans - Comparison with other estimates
The Surface Freshwater Fluxes into the World Oceans
replaces previous publications based on the data of 161 discharge stations (GRDC, 1996), 181 stations (GRDC, 1998), or using another method of flux estimation (GRDC, 2004).