The role of anthropogenic aerosol and other climate factors on the trend of solar radiation during recent decades in Italy.

The specific research role of CeSIA in this project is to analyse the effect of anthropogenic aerosol and other climate factors on the trend of solar radiation during recent decades in two representative countries in Europe. First for Italy where, due to an increase in aerosol precursor emissions, an increase in aerosol loading is expected; next for Germany where a decrease in aerosol loading is expected from the last decades because of the stringet emission controls.The prupose of this first report, a complete trend analysis of yearly and monthly means of global solar radiation for the time series of 17 Italian stations is presented. Next, analyses of yearly averaged cludiness, sunshine and water vapour are illustrated. Finally, the yearly means of atmospheric transmission for days with different cloud covers are examined for a trend.