 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 evaporation, ΔS is the soil storage variation and R is the cumulated total runoff. Therefore, river discharge can be easily calculated by spatially integrating the simulated time mean total runoff field over distinct catchment basins. Such a simple approach is allowed only when climatic scales are concerned as the relevant variables can be derived as long term means of those computed for forecast purposes.
IRIS is based on the Total Runoff Integrated Pathway (TRIP) dataset, which maps information on land water flow directions onto a 0.5°x0.5° regular global grid.
The above figure shows the results of the hind-cast run. The blue line is the modelled seasonal cycle from the runoff fields of the hind-cast run of the Protheus coupled model, forced with the ERA-40 reanalysis , years 1958-1997. For comparison, we also show the observed climatology for the same years (red line), computed from river discharge time series. Only in the case of the Danube river the plotted climatology refers to the period 1958-1984, for which observations are available.
Designing adaptation strategies requires a fundamental understanding of regional climate change and its impact on productive sectors. The main objectives of our research is the applications of weather-driven physiologically based demographic models (PBDMs) used to analyze a major Mediterranean crop-pest system, namely olive (Olea europaea) and the olive fruit fly (Bactrocera oleae) (Center for the Analysis of Sustainable Agro-ecological Systems).
The Mediterranean Basin is expected to be particularly vulnerable to climate change including pronounced climate warming and desertification. The tight co-evolution links of drought-resistant olive and its major pest the olive fly, and their wide distribution makes the system a suitable model for climate change studies.
Figure. Olive yield (kg dry matter tree-1) in the Mediterranean Basin: average (a, b) and standard deviation (c, d) for the period 1958-1967 and 1988-1997.
The West African Monsoon is a climatological feature of major s