干旱区生态环境知识资源中心

A classification of the different aerosol types present over the maritime area-of the "Gulf of Cadiz (Spain)", is carried out as a first step to establish the aerosol climatology of this area. Remote sensing measurements obtained by a Li-Cor spectroradiometer at ground level during the 1996-1999 period have been used. This classification is based on the spectral aerosol characteristics: aerosol optical depth at selected wavelengths and the definition of three different alpha parameters (dynamic alpha) in three independent spectral ranges: Ultraviolet (UV), Visible-infrared (VIS-NIR) and Infrared (IR) intervals. The analysis of the corresponding scatter plots between AOD-alpha parameters and known general aerosol models, permits to establish the ranges of values for the discrimination of the different types of aerosol in our station. This classification is validated with a back trajectory air mass analysis on aerosol origin for 'pure case aerosol type' and applied to the whole database where four categories of pure aerosol types: maritime, arctic, continental and desert, has been considered.