comparison of algorithms and retrieval results

Abstract. This study presents two scientific and one oper-ational retrieval algorithms used to obtain vertical distribu-tions of bromine monoxide (BrO) from observations of the scattered solar light performed by the SCIAMACHY instru-ment in limb viewing geometry. The study begins with a discussion of the theoretical basis of all algorithms followed by an investigation of the retrieval sensitivity. Simulations with three different radiative transfer models allow us to an-alyze influence of the forward model implementation upon the retrieval results. By means of synthetic retrievals we ana-lyze major sources of uncertainties in the resulting BrO pro-files such as different BrO cross sections, their temperature dependence, and stratospheric aerosols. Finally, the reliabil-ity of SCIAMACHY BrO profile retrievals is demonstrated comparing results from different algorithms to each other and to balloon-borne observations.