Monitoring surface UV-B irradiance from space using GOME; comparisons with ground-based measurements

Abstract

Since UV exposure increase may have several harmful effects on human health or ecosystems and given that the ozone depletion has not yet reached its maximum, the necessity for monitoring the surface UV radiation is of great importance. Satellite measurements are the only way to achieve a global view of the radiative fields.

We present some preliminary results of global UV fields estimation at the Earth's surface computed using data from the Global Ozone Monitoring Experiment (GOME) instrument. A first simple model is used to test the best strategy for implementing the cloud modeling. It relies heavily on the cloud coverage estimation from GOME. We have compared this scheme with a more accurate model derived from the algorithm developed for the Total Ozone Mapping Spectrometer (TOMS) instrument by NASA/GSFC. First comparisons of the daily CIE weighted irradiance showed deviations between satellite estimates and measurements as large as a factor of 2.5. Possible explanations are discussed. A first comparison between the two different satellite models is also presented.