Comparison of satellite based observations of Saharan dust source areas

摘要: Abstract Satellite remote sensing products such as Meteosat Second Generation (MSG) Infra Red (IR) dust index and Ozone Monitoring Instrument (OMI) Aerosol Index (AI) are commonly used to infer source areas. Here, two methods for identification compared, (1) a “back-tracking” method applied 15-minute MSG IR index, (2) “frequency” daily OMI AI MODIS DeepBlue Optical Thickness (AOT) data. Using the method, areas inferred by tracking individual plumes back their place of origin, allowed high temporal resolution images. Deep Blue AOT available on only, which does not allow back-tracking plumes. Thus, identified relating frequencies occurrence loadings The spatial distribution only from methods, but also satellite products, shows significant differences. highlights frequent emission sources within complex terrain, while values emphasise topographic basins important Dust retrieved AOTs generally further south towards Sahel region. This study that is key issue in identifying Both, annual cycle strongly depend acquisition time related start emission.