Intercomparison of BrO measurements from ERS-2 GOME, ground-based and balloon platforms

• Published in: Advances in space research 2002-01, Vol.29 (11), p.1661-1666
• Main Authors: Van Roozendael, M, Wagner, T, Richter, A, Pundt, I, Arlander, D.W, Burrows, J.P, Chipperfield, M, Fayt, C, Johnston, P.V, Lambert, J.-C, Kreher, K, Pfeilsticker, K, Platt, U, Pommereau, J.-P, Sinnhuber, B.-M, Tørnkvist, K.K, Wittrock, F
• Format: Article
• Language: English
• ISSN: 0273-1177; 1879-1948
• DOI: 10.1016/S0273-1177(02)00098-4

The consistency of BrO column amounts derived from GOME spectra and from correlative ground-based and balloon measurements performed in 1998-1999 during the Third European Stratospheric Experiment on Ozone (THESEO) has been investigated. The study relies on UV-visible observations at several mid- and high latitude ground-based stations in both hemispheres, complemented by balloon-borne solar occultation profile measurements and 3D chemical transport model simulations. Previous investigations have reported GOME BrO columns systematically larger than those deduced from balloon, suggesting BrO being present, possibly ubiquitously, in the free troposphere. The robustness of this hypothesis has been further tested based on the presently available correlative data set. It is shown that when accounting for the BrO diurnal variation and the solar zenith angle dependency of the sensitivity of correlative data to the troposphere, measurements from all platforms are consistent with the presence of a tropospheric BrO background of 1–3 ×10 13 molec/cm 2 extending over mid- and high latitudes.