L'article du mois ( novembre 2017)
Atmospheric Correction of Multi-Spectral Littoral Images Using a PHOTONS/AERONET-Based Regional Aerosol Model
Bru D., Lubac B., Normandin C., Robinet A., Leconte M., Hagolle O., Martiny N. and Jamet C. Remote Sensing 2017, 9, 814
Spatial resolution is the main instrumental requirement for the multi-spectral optical space missions that address the scientific issues of marine coastal systems. This spatial resolution should be at least decametric. Aquatic color data processing associated with these environments requires specific atmospheric corrections (AC) suitable for the spectral characteristics of high spatialresolution sensors (HRS) as well as the high range of atmospheric and marine optical properties. The objective of the present study is to develop and demonstrate the potential of a ground-based AC approach adaptable to any HRS for regional monitoring and security of littoral systems.
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L'article du mois ( avril 2017)
Variability and trends of wet season temperature in the Sudano-Sahelian zone and
relationships with precipitation
Boutheina Oueslati, Pierre Camberlin, Joël Zoungrana, Pascal Roucou, Saliou Diallo (2017) Climate Dynamincs, in press.
Tendances mensuelles et annuelles des températures maximales au Burkina-Faso (1959-2008), en degrés par décennie. Rouge plein : données brutes, tirets rouges : après déduction de l’effet des précipitations. En bas : tendances des précipitations.
The relationships between precipitation and temperature in the central sudano-sahelian belt are investigated by analyzing 50 years (1959-2008) of observed temperature (Tx and Tn) and rainfall variations. At daily time-scale, both Tx and Tn show a marked decrease as a response to rainfall occurrence, with a strongest departure from normal one day after the rainfall event (-0.5 to -2.5°C depending on the month).
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L'article du mois ( janvier 2017)
Characterisation of Heat Waves in the Sahel and Associated Physical Mechanisms
Oueslati B, B Pohl, V Moron, S Rome & S Janicot (2017) Journal of Climate, in press.
Large efforts are made to address Heat Waves (HWs) in developed countries because of their devastating impacts on society, economy and environment. However, HWs are still understudied over developing countries. This is particularly true in West Africa, and especially in the Sahel, where temperatures recurrently reach critical values, such as during the 2010 HW event in Western Sahel. Our work aims at characterizing the Sahelian HWs during boreal spring seasons (April-May-June) and understanding the mechanisms associated with such extreme events. Over the last three decades, Sahelian HWs have been becoming more frequent, lasting longer, covering larger areas and reaching higher intensities.
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L'article du mois ( février 2017)
Frost stress evolution and winter pea ideotype in the context of climate warming at a regional scale
Thierry Castel, Christophe Lecomte, Yves Richard, Isabelle Lejeune-Hénaut, Annabelle Larmure (2017) OCL, in press.
Boxplot of the inter-annual frost stress index computed from observed (station) and interpolated (grid) climate data.
Le pois (Pisum sativum L.) est une culture majeure des régions tempérées implantée pour ses graines riches en protéines. Il est particulièrement sensible aux stress abiotiques. L'augmentation brutale des températures observée en Europe en 1987/1988 appelée “rupture climatique” questionne sur les performances future du pois d'hiver dans ce climat changeant.
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L'article du mois (décembre 2016)
Towards understanding the epidemiology of Neisseria meningitidis in 4 the African meningitis belt: a multi-disciplinary overview
Lydiane Agier, Nadège Martiny, Oumy Thiongane, Judith E. Mueller, Juliette Paireau, Eleanor R. Watkins, Tom J. Irving, Thibaut Koutangni, Hélène Broutin
Objectives: Neisseria meningitidis is the major cause of seasonal meningitis epidemics in the African meningitis belt. In the changing context of a reduction in incidence of serogroup A and an increase in incidence of serogroups W and C and of Streptococcus pneumoniae, a better understanding of the determinants driving the disease transmission dynamics remains crucial to improving bacterial meningitis control.
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