Antarctic precipitation, clouds and their interplay with aerosols: Combining ground-based remote sensing and regional climate modeling.

Precipitation and clouds play a key role in the Earth’s climate system. Clouds are an essential component in the conversion chain from atmospheric water vapor to precipitation. In turn, precipitation determines the water availability at the surface of the earth. Similarly for Antarctica, where precipitation is the only source of mass to the ice sheet. Despite the importance of Antarctic precipitation and clouds, their representation in climate models remains problematic. This is unfortunate, as variations in precipitation will largely determine the contribution of the Antarctic ice sheet to sea level change. Natural and anthropogenic aerosols play a crucial role in the formation of clouds and precipitation. Since precipitation, cloud and aerosol processes are intertwined, only models that correctly represent these processes can give reliable future climate projections. The main objective of this proposal is to improve the understanding and modeling of precipitation, clouds and their interaction with aerosols in Dronning Maud Land (East Antarctica). In 2009, a unique meteorological-cloud-precipitation-aerosol observatory has been established in this region, namely at the Belgian Princess Elisabeth station. This suite of ground-based observations will be combined with satellite observations to evaluate and improve an advanced high-resolution regional climate model. Subsequently, this model will be used to analyze the role of aerosols in determining Antarctic snowfall amounts.