Impact of land use and soil data specifications on COSMO-CLM simulations in the CORDEX-MED area

The impact of the ECOCLIMAP land use and the Harmonized World Soil Database (HWSD) data on simulations with the Consortium for Small-scale Modeling model in CLimate Mode (CCLM) regional climate model is investigated. ECOCLIMAP has information about vegetation characteristics as monthly data for 215 climatic units. With the HWSD implementation in CCLM, the spatial resolution of the soil data has been increased to 30 arc seconds and has an improved texture definition and handling in the soil model TERRA_ML. Simulations in the MED-CORDEX modeling domain over the period 1986-2000 reveal that differences of up to 1.8 K in the area monthly mean temperature as well as of up to 21% in the area monthly mean precipitation can be attributed to the differences in the soil data time-invariant boundary input. Differences related to changes in land use are with 0.4 K and 5% moderate. Differences resulting from the soil data and its processing in CCLM indicate that regional climate model simulations might benefit from further improvements in this area.