High-Resolution WRF Model Simulations of Critical Land Surface-Atmosphere Interactions Within Arid and Temperate Climates (WRFCLIM)

The interaction of the Earth’s surface with the atmosphere is a key component that needs to be well represented in atmospheric models to increase the accuracy of numerical weather prediction and climate projections. The Weather Research and Forecasting (WRF) model was applied to investigate the model sensitivity to its physics parametrizations and the impact of land use changes in temperate continental and arid regions. Results show that the model is more sensitive to the land surface model than to the boundary layer parametrization. Furthermore, the impact of land surface processes is not constrained to the lower boundary layer. It extends up to the boundary layer top, influencing the strength and the location of convection and precipitation. The study underscores the demand for research on parametrization schemes for model applications at high resolution based on data sets from novel observing systems of the atmosphere. In a land use change impact study the influence of deforestation on the weather in the temperate climate of Germany has been investigated. The results show a decrease in temperature, an increase in humidity, and overall a decrease in precipitation. Large-scale plantations in coastal arid regions can contribute to mitigation methods of anthropogenic climate change, through storage of atmospheric CO2. Results of WRF simulations indicate that rainfall events can be triggered by large arid plantations, but the strength and probability of such events is governed by regional climate. This indicates that impacts can be controlled via intelligent placement of such schemes. Thus, desert plantations have the potential not only to mitigate climate change but also to increase precipitation in arid regions and reverse desertification.