Seven years of global retrieval of cloud properties using space-borne data of GOME
1Institute of Environmental Physics and Remote Sensing, University of Bremen, Otto-Hahn-Allee 1, 28334 Bremen, Germany
2Atmospheric, Oceanic & Planetary Physics, University of Oxford, Oxford, UK
3Remote Sensing Group, STFC Rutherford Appleton Laboratory, Chilton, UK
*now at: Goddard Earth Sciences Technology And Research (GESTAR), NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
Abstract. We present a global and regional multi-annual (June 1996–May 2003) analysis of cloud properties (spherical cloud albedo – CA, cloud optical thickness – COT and cloud top height – CTH) of optically thick (COT > 5) clouds, derived using measurements from the GOME instrument on board the ESA ERS-2 space platform. We focus on cloud top height, which is obtained from top-of-atmosphere backscattered solar light measurements in the O2 A-band using the Semi-Analytical CloUd Retrieval Algorithm SACURA. The physical framework relies on the asymptotic equations of radiative transfer. The dataset has been validated against independent ground- and satellite-based retrievals and is aimed to support trace-gases retrievals as well as to create a robust long-term climatology together with SCIAMACHY and GOME-2 ensuing retrievals. We observed the El Niño-Southern Oscillation anomaly in the 1997–1998 record through CTH values over the Pacific Ocean. The global average CTH as derived from GOME is 5.6 ± 3.2 km, for a corresponding average COT of 19.1 ± 13.9.