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Measurements by the hyperspectral spectrometers GOME, SCIAMACHY and GOME-2 are used to determine the rate of linear change (and trends) in cloud top height (CTH) in the period between June 1996 and May 2012. The retrievals are obtained from Top-Of- Atmosphere (TOA) backscattered solar light in the oxygen A-band using the Semi-Analytical CloUd Retrieval Algorithm SACURA. The physical framework relies on the asymptotic equations of radiative transfer, valid for optically thick clouds. Using linear least-squares techniques, a global trend of -1.78±2.14myr-1 in deseasonalized CTH has been found, in the latitude belt within ±60°, with diverging tendencies over land (+0.27±3.2myr-1) and ocean (-2.51±2.8myr-1). The El Niño-Southern Oscillation (ENSO), strongly coupled to CTH, forces clouds to lower altitudes. The global ENSO-corrected trend in CTH amounts to -0.49±2.22myr-1. At a global scale, no explicit regional pattern of statistically significant trends (at 95% confidence level, estimated with bootstrap technique) have been found, which would be representative of typical natural synoptical features. One exception is North Africa, which exhibits the strongest upward trend in CTH sustained by an increasing trend in water vapour. [ABSTRACT FROM AUTHOR]

Measurements by the hyperspectral spectrometers GOME, SCIAMACHY, and GOME-2 are used to determine the rate of linear change (and trends) in cloud top height (CTH) in the period between June 1996 and May 2012. The retrievals are obtained from Top-Of-Atmosphere (TOA) backscattered solar light in the oxygen A-band using the Semi-Analytical CloUd Retrieval Algorithm SACURA. The physical framework relies on the asymptotic equations of radiative transfer, valid for optically thick clouds. Using linear least-squares techniques, a global trend of -1.78±2.14myr-1 in deseasonalised CTH has been found, in the latitude belt within ±60°, with diverging tendencies over land (+0.27±3.2myr-1) and ocean (-2.51±2.8myr-1). The El Niño-Southern Oscillation (ENSO), strongly coupled to CTH, forces clouds to lower altitudes. The global ENSO-corrected trend in CTH amounts to -0.49±2.22myr-1. At a global scale, no explicit regional pattern of statistically significant trends (at 95% confidence level, estimated with bootstrap technique) have been found, which would be representative of typical natural synoptical features. One exception is North Africa, which exhibits the strongest upward trend in CTH sustained by an increasing trend in water vapor. [ABSTRACT FROM AUTHOR]

The article presents an analysis of a cloud properties derived using measurements from the GOME instrument on board the European Space Agency (ESA) ERS-2 space platform. The properties examined include the spherical cloud albedo, cloud optical thickness and cloud top height. The analysis also uses the Semi-Analytical CloUd Retrieval Algorithm (SACURA) to obtain the cloud top height top-of-atmosphere backscattered solar light measurements in the O2 A-band.

The article presents a study which aims to describe the retrieval of cloud properties using measurements from the Global Ozone Monitoring Experiment-1 (GOME-1) instrument. The study analyzed cloud top height (CTH) and used the asymptotic equations of radiative transfer while dataset was validated and compared. Results show that global average CTH is 7.0±1.18 kilometer (km) and analytical forms of probability density functions is suitable in climate modeling parameterization.