  A study for the comprehensive information of current UV exposure for the area
of Germany, based on the method for near real time calculation of UV Index maps
used in the framework of the Austrian UV Monitoring Network, is presented. For
the area of Germany about 22.000 surface UV Index maps were calculated for the
year 2022 via the radiative transfer model libRadtran by incorporating daily
forecast data for ozone, albedo and aerosols from the Copernicus Atmospheric
Monitoring Service and taking into account cloud information gathered from
SEVIRI data of Meteosat Second Generation in the form of a cloud modification
factor. Ground-based measurements of 17 stations of the German Solar Monitoring
Network were then compared to the modelled maps. For most stations the
correlation coefficient between measured and modelled UV Index (UVI) is above
0.92 and the mean difference of modelled UVI to measured UVI is smaller than
0.5 UVI. The modelling of the UVI at the high mountain station Schneefernerhaus
is associated with higher uncertainties (correlation coefficient 0.85 and mean
UVI difference 0.6 UVI) due to the small-scale topography with spatially highly
variable albedo and clouds. Moreover, case studies for specific locations with
respect to cloud conditions and topography are discussed, as well as a case
study of the combination of ground-based measurements and modelled UVI maps in
form of spatial correction factors.
