The Regional Brewer Calibration Center - Europe: an overview of the X Brewer Intercomparison Campaign

Abstract

The X Regional Brewer Calibration Center - Europe (RBCC-E) intercomparison campaign was held at El Arenosillo atmospheric sounding station of the Instituto Nacional de Tecnica Aeroespacial (INTA) during the period of May 25th – June 5th, 2015. This X Brewer intercomparison campaign was a joint effort of EUBREWNET and the Area of Instrumentation and Atmospheric Research of INTA, with the support of COST Action 1207. Twenty one Brewer instruments from eleven countries participated at the El Arenosillo campaign. In addition, the solar UV irradiance calibration was performed by the traveling reference standard QASUME of the World Calibration Center for UV (WCC-UV). This work shows a general overview of the ozone comparison focused on the correction of the stray light effect for the single-monochromator Brewer spectrophotometer derived by the comparison with a reference double-monochromator Brewer. At the beginning of the campaign, 16 out of the 21 participating Brewer instruments (76%) agreed to better than ± 1%, and 10 instruments (50%) agreed to better than ± 0.5%. After applying the final calibration that included the stray light correction, all working instruments agreed at the ± 0.5% level.