The Effects of Model-Generated Climatic Changes due to a CO2 Doubling on Desertification Processes in the Mediterranean Area
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For the estimation of a climatic change induced by a doubling of atmospheric CO2 we use the results of three-dimensional general circulation models (GCM). Although the results from present climate modeling cannot be considered as predictions of future climatic conditions due to the inherent models’ deficits, they can still serve a useful purpose in climate change scenarios. The reason for this is that climate models are the only tools available to study the response of the climate system to a perturbation in a physically consistent manner and that such types of models can provide a consistent data set of high temporal and spatial resolution. For the Mediterranean area, the results obtained from three different GCMs, namely, the British Meteorological Office model (BMO), the Goddard Institute of Space Studies model (GISS), and the National Center for Atmospheric Research model (NCAR) are shown. The regional and seasonal distributions of temperature, precipitation, and soil moisture are used to study the potential for desertification. The results indicate that the CO2-induced changes for temperature generated by the three models are quite similar. The values of the area mean change range between 2.5 and 4.2 K. The precipitation response results in a diverse pattern. The physical mechanisms likely to be responsible for the climatic changes are identified and their statistical significance is tested. This type of work will help us develop the methodology and assist us in gaining insight into the use of climate model scenarios for impact analysis.
KeywordsSoil Moisture General Circulation Model Climatic Change Scenario Ocean Heat Transport Soil Moisture Change
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- 1.Bach, W. (1984). Our threatened climate: Ways of averting the CO2-problem through rational energy use, Reidel Publ. Co., Dordrecht.Google Scholar
- 2.Bach, W., Jung, H.J. and Knottenberg, H. (1984). Developments of regional climate scenarios. In: Socioeconomic impacts of climatic changes, Report for the EEC and the BMFT, Dornier System, Friedrichshafen.Google Scholar
- 5.Gates, W.L. (1983). The use of general circulation models in the analysis of the ecosystem impacts of a climatic change. Paper presented at the Study Conference on the sensitivity of ecosystem and society to climatic change, Villach, 19–23 September, 1983.Google Scholar
- 6.Gates, W.L. and Bach, W. (1981). Analysis of a model simulated climate change as a scenario for impact studies. Report for the German Federal Environmental Agency, R&D No. 104-102-513, 163pp.Google Scholar
- 8.Hansen, J., Lacis, A., Rind, D., Russell, G., Stone, P., Fung, J., Lerner, J., Ruedy, R. (1984). Climate sensitivity experiments with a threedimensional model: Analysis of feedback mechanisms (unpublished manuscript).Google Scholar
- 17.Schlesinger, M.E. (1983). Simulating CO2-induced climatic change with mathematical climate models: Capabilities, limitations and prospects, III3–III139, US DOE 021, Washington, D.C..Google Scholar
- 18.US NRC (1983). Changing climate, National Academy Press., Washington, D.C..Google Scholar
- 19.Washington, W.M. and Meehl, G.A. (1984). Seasonal cycle experiments on the climate sensitivity due to a doubling of CO2 with an atmospheric general circulation model coupled to a simple mixed layer ocean model, J. Geophys. Res. (in press).Google Scholar