Measurements of total ozone amount over Badajoz (Southwestern Spain) by means of a GUV multiband radiometer

Abstract

This paper presents the first measurements of total ozone amount performed at the radiometric station of Badajoz (Spain) by means of a multichannel radiometer GUV-2511. The retrieval of total ozone amount from GUV measurements of solar ultraviolet irradiance is performed with the support of look-up tables calculated using the SBDART radiation transfer code. This methodology is based on the different absorption by ozone suffered by the radiation at two certain near wavelengths. In this case the pair 305, 340 nm was chosen because of its better performance than the pair 305, 320 nm. The look-up table contains the ratio between irradiances at the mentioned wavelengths calculated under different theoretical conditions of solar zenith angle and total ozone amount. The estimations of actual total ozone amount are calculated applying the look-up table to the experimental irradiance ratios as measured by the GUV radiometer. In order to validate these estimations, they are compared with the values provided by the OMI (Ozone Monitoring Instrument) aboard NASA EOS/Aura satellite during April 2010. Results indicate a general good agreement between both datasets, showing a notable dependence with the cloudiness conditions.