 annual mean Mediterranean discharge with an accuracy of about 78%, see Fig.1
Fig. 1 Climatological seasonal cycle of total discharge into the Mediterranean Sea and its decomposition by continent of origin. Represented here is at least 78% of the actual Mediterranean totals (solid line), 76% of discharge from Europe (short dashed), 40% of that from the Middle East (dotted), and 86% of discharge from North Africa (long dashed). (Values are in m3/s.) From "River Discharge into the Mediterranean Sea: Climatology and Aspects of the Observed Variability" , M.V. Struglia, A. Mariotti, A. Filograsso, Journ. Clim. Vol.17 (2004), No. 24 pp. 4740-4751.
Regional projections of river discharge in the Mediterranean catchment
Among all the possible physical impacts of climate change in the Mediterranean area, the one related to the availability of water resources is crucial both for natural equilibrium of biological ecosystems and for social and economic activities of the inhabitants of the Mediterranean countries. Projected variations in river discharge deriving from altered rainfall distribution will dramatically affect both natural equilibriums and people, as some areas are liable to experience large increases in flood flows, whereas others will be subject to water stress.
We developed IRIS (Interactive River Scheme) which is a numeric tool to estimate river discharge from modelled total runoff fields. Runoff fields are computed by atmospheric models via a soil parameterization scheme, which accounts for energy and water fluxes at the atmosphere-biosphere-land interfaces, thus determining the moisture content of soil, the quantity of water returned to the atmosphere through evapo-transpiration and the excess rainfall that goes into runoff.
Fig.2 Mediterranean and Black Sea catchments in IRIS. Reconstruction based on TRIP datase
On sufficiently long time scales, vertical balance between the four components of the terrestrial hydrological cycle should be achieved:
where P is the cumulated precipitation, E is the cumulated eva