ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-3-145-2003 Application of the Spectral Structure Parameterization technique: retrieval of total water vapor columns from GOME Lang R. 1 2 3 Williams J. E. 1 van der Zande W. J. 1 Maurellis A. N. 2 FOM-Institute for Atomic and Molecular Physics, Amsterdam, The Netherlands SRON National Institute for Space Research, Utrecht, The Netherlands Department of Physics and Astronomy, Vrije Universiteit, Amsterdam, The Netherlands 11 02 2003 3 1 145 160 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys.net/3/145/2003/acp-3-145-2003.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/3/145/2003/acp-3-145-2003.pdf

We use a recently proposed spectral sampling technique for measurements of atmospheric transmissions called the Spectral Structure Parameterization (SSP) in order to retrieve total water vapor columns (WVC) from reflectivity spectra measured by the Global Ozone Monitoring Experiment (GOME). SSP provides a good compromise between efficiency and speed when performing retrievals on highly structured spectra of narrow-band absorbers like water vapor. We show that SSP can be implemented in a radiative transfer scheme which treats both direct-path absorption and absorption by singly-scattered light directly. For the retrieval we exploit a ro-vibrational overtone band of water vapor located in the visible around 590 nm. We compare our results to independent values given by the data assimilation model of ECMWF. In addition, results are compared to those obtained from the more accurate, but more computationally expensive, Optical Absorption Coefficient Spectroscopy (OACS).