ESA Earth Home Missions Data Products Resources Applications
EO Data Access
How to Apply
How to Access
Site Map
Frequently asked questions
Terms of use
Contact us



BrO Profiling from Ground-based DOAS Observations: New Tool for the ENVISAT/SCIAMACHY Validation

Francois Hendrick(1), Michel Van Roozendael(2), Martine De Maziere(1), Andreas Richter(3), Alexei Rozanov(3), Christopher Sioris(4), Sven Kuehl(5), Janis Pukite(5) and Thomas Wagner(5)

(1) Belgian Institute for Space Aeronomy (IASB-BIRA), 3, Avenue Circulaire, 1180 Brussels, Belgium
(2) Belgian Institute for Space Aeronomy (IASB-BIRA), 3, Avenue Circulaire, 1180, Belgium
(3) IUP/IFE Bremen, University of Bremen, Bremen, Germany
(4) Harvard-Smithsonian Center for Astrophysics, ?, Cambridge, United States
(5) IUP/IFE Heidelberg, University of Heidelberg, Heidelberg, Germany


A profiling algorithm has been developed at IASB-BIRA in order to provide low vertical resolution BrO profile in the 0-37 km altitude range from ground-based zenith-sky DOAS observations. This algorithm is based on the Rodgers Optimal Estimation Method (OEM) and includes a validated forward model accounting for the transfer of the multiply scattered radiation in a pseudo-spherical atmosphere and the diurnal variation of the stratospheric BrO. It has been applied to the ground-based zenith-sky UV-visible observations continuously performed at the NDSC station of Harestua (60°N, Southern Norway) since 1998. The reliability of our BrO retrievals has been also verified through correlative comparisons with SAOZ and LPMA/DOAS balloon measurements.

Here, the time-series of stratospheric and tropospheric BrO profiles and columns retrieved at the Harestua station are used to validate limb and nadir ENVISAT/SCIAMACHY scientific products for the 2002-2004 period. Retrieval algorithms from the following groups are involved in the validation exercise: IUP/IFE Bremen, IUP/IFE Heidelberg, and Harvard Smithsonian for limb BrO profiles and, IASB-BIRA, IUP/IFE Bremen, and IUP/IFE Heidelberg for nadir BrO total columns. Comparisons between ground-based UV-visible and SCIAMACHY data are also performed in the same photochemical conditions since the profiling algorithm includes a stacked box photochemical model, enabling the retrieval of BrO profiles at any solar zenith angle.


Full paper

Keywords: ESA European Space Agency - Agence spatiale europeenne, observation de la terre, earth observation, satellite remote sensing, teledetection, geophysique, altimetrie, radar, chimique atmospherique, geophysics, altimetry, radar, atmospheric chemistry