Satellite retrievals of dust aerosol over the Red Sea and the Persian Gulf (2005–2015)
KAUST DepartmentEarth Science and Engineering Program
Physical Science and Engineering (PSE) Division
KAUST Grant NumberCRG-1-2012-STE- IMP
Permanent link to this recordhttp://hdl.handle.net/10754/625230
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AbstractThe inter-annual variability of the dust aerosol presence over the Red Sea and the Persian Gulf is analysed over the period 2005-2015. Particular attention is paid to the variation in loading across the Red Sea, which has previously been shown to have a strong, seasonally dependent latitudinal gradient. Over the 11 years considered, the July mean 630 nm aerosol optical depth (AOD) derived from the Spinning Enhanced Visible and InfraRed Imager (SEVIRI) varies between 0.48 and 1.45 in the southern half of the Red Sea. In the north, the equivalent variation is between 0.22 and 0.66. The temporal and spatial pattern of variability captured by SEVIRI is also seen in AOD retrievals from the MODerate Imaging Spectroradiometer (MODIS), but there is a systematic offset between the two records. Comparisons of both sets of retrievals with ship-and land-based AERONET measurements show a high degree of correlation with biases of < 0.08. However, these comparisons typically only sample relatively low aerosol loadings. When both records are stratified by AOD retrievals from the Multi-angle Imaging SpectroRadiometer (MISR), opposing behaviour is revealed at high MISR AODs (> 1), with offsets of C 0.19 for MODIS and 0.06 for SEVIRI. Similar behaviour is also seen over the Persian Gulf. Analysis of the scattering angles at which retrievals from the SEVIRI and MODIS measurements are typically performed in these regions suggests that assumptions concerning particle sphericity may be responsible for the differences seen.
CitationBanks JR, Brindley HE, Stenchikov G, Schepanski K (2017) Satellite retrievals of dust aerosol over the Red Sea and the Persian Gulf (2005–2015). Atmospheric Chemistry and Physics 17: 3987–4003. Available: http://dx.doi.org/10.5194/acp-17-3987-2017.
SponsorsJamie Banks and Kerstin Schepanski acknowledge funding through the Leibniz Association for the project