This service provides daily irradiation (daily sum of irradiance) in UVA, UVB and erythemal spectral regions at a given location, expressed as latitude and longitude, and for several days.

The irradiation is an energy, expressed here in Wh/m2. Multiply by 0.36 to obtain J/cm2, or by 3600 to obtain J/m2. Divide the irradiation in Wh/m2 by 24 h to obtain the mean irradiance for a day in W/m2.

For each day, this service provides the three spectral components, plus a reliability index, ranging from 1 to 5 and indicating the number of hourly values used for the construction of the daily sum.

Using the "SoDaCommaSeparatedValue" as output format is convenient for further importation of the results into a spreasheet.

The irradiation database underlying the service is the HelioClim database, computed from the series of Meteosat images. The algorithm for the spectral decomposition is that of the Belgium meteorological office (Institut Royal de Météorologie, Joukoff and co-workers), presented in the European Solar Radiation Atlas (see the ESRA handbook, volume 2).