Aerosol columnar characterization in Morocco: ELT prospect.

• Main Authors: Bounhir, A., Benkhaldoun, Z., Mougenot, Bernard, Sarazin, B., Siher, E., Masmoudi, L.
• Other Authors: Département de Physique Appliquée, departement de physique appliquée, LPHEA - Departement de Physique (LPHEA), Département de physique, Centre d'études spatiales de la biosphère (CESBIO), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), European Southern Observatory (ESO), Faculté des sciences Rabat, Université Mohammed V de Rabat Agdal (UM5)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2008
• Subjects: site testing; atmospheric effects; data analys is; photometer; [SDV.EE.ECO]Life Sciences [q-bio]/Ecology; environment/Ecosystems; Aerosol Robotic Network
• Online Access: https://ird.hal.science/ird-00390757; https://ird.hal.science/ird-00390757/document; https://ird.hal.science/ird-00390757/file/Bounhir_2008_NewAstronomy_souspresse.pdf

The work presented in this paper focuses on site testing in terms of aerosol loadings where ground based measurements are essential. In our case they are materialized by the aerosol optical thickness (AOT) and are provided by the AERONET (Aerosol Robotic Network) network from four stations, Dakhla and Marrakech in Morocco and Santa-Cruz and Izana in the Canary Islands. To fully scan all the area of the Moroccan territories, satellite measurements are certainly the most efficient way. We used the most popular and reliable products. TOMS (Total Ozone Mapping Spectrometer) aerosol index (AI) provided by both TOMS Earth Probe and TOMS OMI (Ozone Monitoring Instrument) along with aerosol optical thicknesses provided by MODIS (Moderate Resolution Imaging Spectroradiometer) and MISR (Multiangle Imaging Spectroradiometer) instruments, onboard Terra platform. The idea is to compare sensing capabilities of each instrument in the region under study, in order to know which is suitable for a given place and when. For that purpose linear regression analysis were performed between satellite data and AERONET observations. Good correlations were observed with the Pearson correlation coefficient, R, varying from 0.68 to 0.92 for MODIS, MISR and TOMS OMI, and from 0.54 to 0.74 for TOMS EP. A ten years analysis of the TOMS EP index has been performed with a calibration of the aerosol index into TOMS retrieved aerosol optical thickness in the area of interest (Morocco and Canary Islands) and an inter-comparison with the other products was achieved. In the frame of the ELT (Extremely Large Telescope) project prospect, once the appropriate satellite instrument have been chosen and the area scanned, the next step would be to scan aerosol loadings at higher altitude locations. Since vertical d istribution of aerosol optical thickness and microphysical properties are not well understood and modelized, we used the relationships related to Izana (Izana's altitude is 2367 m), as a first attempt, to extrapolate the aerosol optical thickness ...