| Aerosols are an important element of global climate. Their effect on the atmospheric radiation budget shows large regional differences. With multi-spectral imagers, like MODIS, the horizontal distribution of aerosols has been determined. However, the vertical distribution of aerosols has not yet been determined from passive remote sensing. From modelling we have found that it is possible to derive this information from polarization measurements in the O2 A-band at 760 nm. The Japanese satellite GOSAT, to be launched in 2009, is the first satellite to measure the polarization in O2 and CO2 absorption bands. The main aim of GOSAT is to determine the global distribution of CO2 and CH4 from space. We want to analyse and exploit the novel GOSAT polarization measurements to: (1) understand the polarization in the O2 and CO2 bands as compared to modelling; (2) derive the altitude of aerosols from GOSAT polarization measurements in the O2 A-band, and compare with active remote sensing results of aerosol altitude from CALIPSO; (3) contribute to an estimate of the error in CO2 column retrievals from GOSAT (and OCO) due to aerosol altitude uncertainty. |
