Satellite study over Europe to estimate the single scattering albedo and the aerosol optical depth

Abstract

Aerosol particles have a significant effect on the Earth climate on regional and global scales by perturbing the radiation balance both directly due to scattering and absorption of solar radiation and indirectly due to their effect on cloud macroscopic and microphysical properties (IPCC 2007 [1]). One of the main contributors to the radiative effect of aerosols is the Single Scattering Albedo (SSA). One of the research topics is the uncertainty in estimating and improving the SSA value. In radiative transfer studies, single scattering albedo is the ratio of scattering optical depth and the total optical depth of the atmosphere. The SSA and the Aerosol Optical Depth (AOD) are two of the main parameters to estimate aerosol radiative forcing. In this study we show results of the SSA and the AOD at 0.555 μm retrieved from Advanced Along Track Scanning Radiometer (AATSR) data, with focus on forest fires over Europe. The retrieval results are validated using AERONET AOD level 2.0 data and the SSA is compared with the AERONET level 2.0 inversion product. The SSA is a new AATSR product; it is obtained with a new method, based on aerosol Look-Up Tables (LUT), for selected aerosol size distribution, with given refractive index. The LUTs are used together with the contribution in the AOD fraction of absorbing and non-absorbing aerosol particles. The SSA can be applied in different studies like the computation of scattering phase function, the characterization of aerosol particles and in radiative transfer models. Preliminary results show a good agreement between the AOD at 0.555 μm from AERONET and AATSR with a correlation coefficient of up to 0.86.