RETRIEVING AEROSOL CHARACTERISTICS FROM SATELLITE OCEAN COLOR MULTI-SPECTRAL SENSORS USING A NEURAL-VARIATIONAL METHOD

D. Diouf, S. Thiria, A. Niang, J. Brajard, M. Crepon

Abstract

We present a new algorithm suitable for retrieving and monitoring Saharan dusts from satellite ocean-color multi-spectral observations. This algorithm comprises two steps. The first step consists in classifying the TOA spectra using a neuronal classifier, which provides the aerosol type and a first guess value of the aerosol parameters. The second step retrieves accurate aerosol parameters by using a variational optimization method. We have analyzed 13 years of SeaWiFS images (September 1997-December 2009) in an Atlantic Ocean area off the coast of West Africa. As the method takes into account Saharan dusts, the number of pixels processed is an order of magnitude higher than that processed by the standard SeaWiFS algorithm. We note a strong seasonal variability. The Saharan dust concentration is maximal in summer during the rainy season and minimal in autumn when the vegetation bloom due to the rainy season prevents soil erosion by the wind.

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Paper Citation


in Harvard Style

Diouf D., Thiria S., Niang A., Brajard J. and Crepon M. (2011). RETRIEVING AEROSOL CHARACTERISTICS FROM SATELLITE OCEAN COLOR MULTI-SPECTRAL SENSORS USING A NEURAL-VARIATIONAL METHOD . In Proceedings of the International Conference on Neural Computation Theory and Applications - Volume 1: NCTA, (IJCCI 2011) ISBN 978-989-8425-84-3, pages 297-303. DOI: 10.5220/0003638802970303


in Bibtex Style

@conference{ncta11,
author={D. Diouf and S. Thiria and A. Niang and J. Brajard and M. Crepon},
title={RETRIEVING AEROSOL CHARACTERISTICS FROM SATELLITE OCEAN COLOR MULTI-SPECTRAL SENSORS USING A NEURAL-VARIATIONAL METHOD},
booktitle={Proceedings of the International Conference on Neural Computation Theory and Applications - Volume 1: NCTA, (IJCCI 2011)},
year={2011},
pages={297-303},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0003638802970303},
isbn={978-989-8425-84-3},
}


in EndNote Style

TY - CONF
JO - Proceedings of the International Conference on Neural Computation Theory and Applications - Volume 1: NCTA, (IJCCI 2011)
TI - RETRIEVING AEROSOL CHARACTERISTICS FROM SATELLITE OCEAN COLOR MULTI-SPECTRAL SENSORS USING A NEURAL-VARIATIONAL METHOD
SN - 978-989-8425-84-3
AU - Diouf D.
AU - Thiria S.
AU - Niang A.
AU - Brajard J.
AU - Crepon M.
PY - 2011
SP - 297
EP - 303
DO - 10.5220/0003638802970303