Precipitation response to aerosol–radiation and aerosol–cloud interactions in regional climate simulations over Europe

Abstract. The effect of aerosols on regional climate simulations presents large uncertainties due to their complex and non-linear interactions with a wide variety factors, including aerosol–radiation (ARI) aerosol–cloud (ACI) interactions. These are strongly conditioned by the meteorological situation type aerosol, but, despite increase, only limited number studies have covered this topic from climatic perspective. This contribution thus aims quantify impacts precipitation inclusion ARI ACI processes in driven ERA20C reanalysis. A series (for period 1991–2010) for Euro-CORDEX domain were conducted + (ARCI), establishing as reference simulation where not included interactively (BASE). results show that effects time-mean spatially averaged over whole limited. However, spatial redistribution occurs when introduced into model, well do changes intensity regimes. main differences respect base-case occur central Europe, decrease is associated depletion rainy days clouds at low level (CLL). reduction strong correlation ratio PM2.5∕PM10, since especially intense during those events high values (pointing levels anthropogenic aerosols) Europe. all ranges rates. On other hand, model produces an increase eastern Mediterranean basin ACIs implemented. Here, change caused presence PM10 (low PM2.5∕PM10 ratios, pointing natural aerosols). In case, higher amount affects rates precipitation. Finally, there some disperse areas leads precipitation, moderate