FIRST VALIDATION OF SCIAMACHY BRO COLUMNS

Abstract

Retrievals of BrO columns using version 5.01 of the SCIAMACHY NRT processor as well as independent non-operational algorithms are compared with GOME and with ground-based measurements from two Arctic stations. NRT BrO columns are found to agree with GOME and non-operational data sets to within 20% for moderate and large slant columns, while for slant columns smaller than 1.5x10 14 molec/cm 2 , the NRT product reports larger values by 20 to 100%. First comparisons with ground-based measurements in Harestua (60°N) and Ny-Alesund (79°), tentatively evaluated at the time of the SCIAMACHY overpasses, provide encouraging results although more work is still needed for a detailed quantitative validation of BrO.