The UVIOS2 model has been evaluated at Davos, Switzerland during the UVCIII campaign. The accuracy in the modelled UV indices has been assessed for different combinations of model inputs. A good overall agreement between UVIOS2 and the world reference spectroradiometer QASUME was found (average ratio of ~1 between the modelled and measured UV index), although the variability in the ratio can be large under cloudy conditions.

The upgraded systems SENSE2 and NextSENSE2 focus on improving the quality of solar nowcasting and forecasting. SENSE2 provides real-time estimates of solar irradiance across a wide region every 15 min. NextSENSE2 offers short-term forecasts of irradiance up to 3 h ahead. Evaluation with actual data showed that the instantaneous comparison yields the most discrepancies due to the uncertainties of cloud-related information and satellite versus ground-based spatial representativeness limitations.

Large-scale retrievals of the ultraviolet index (UVI) in real time by exploiting the modern Earth observation data and techniques are capable of forming operational early warning systems that raise awareness among citizens of the health implications of high UVI doses. In this direction a novel UVI operating system, the so-called UVIOS, was introduced for massive outputs, while its performance was tested against ground-based measurements revealing a dependence on the input quality and resolution.