Éditeur(s) : HAL CCSD Nature Publishing Group
Résumé : International audience
ISSN: 1752-0894

hal-01667978
https://hal.archives-ouvertes.fr/hal-01667978
DOI : 10.1038/s41561-017-0028-x

Éditeur(s) : HAL CCSD
Résumé : International audience
Conférence MISTRALS PAELOMEX
Montpellier, France

hal-01683548
https://hal-univ-tlse2.archives-ouvertes.fr/hal-01683548

Éditeur(s) : HAL CCSD Nature Publishing Group
Résumé : International audience
ISSN: 1752-0894

hal-01668923
https://hal.archives-ouvertes.fr/hal-01668923
DOI : 10.1038/s41561-017-0028-x

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
Understanding the factors underlying the spatio-temporal distribution of infectious diseases provides useful information regarding their prevention and control. Dengue fever spatio-temporal patterns result from complex interactions between the virus, the host, and the vector. These interactions can be influenced by environmental conditions. Our objectives were to analyse dengue fever spatial distribution over New Caledonia during epidemic years, to identify some of the main underlying factors, and to predict the spatial evolution of dengue fever under changing climatic conditions, at the 2100 horizon. We used principal component analysis and support vector machines to analyse and model the influence of climate and socio-economic variables on the mean spatial distribution of 24,272 dengue cases reported from 1995 to 2012 in thirty-three communes of New Caledonia. We then modelled and estimated the future evolution of dengue incidence rates using a regional downscaling of future climate projections. The spatial distribution of dengue fever cases is highly heterogeneous. The variables most associated with this observed heterogeneity are the mean temperature, the mean number of people per premise, and the mean percentage of unemployed people, a variable highly correlated with people's way of life. Rainfall does not seem to play an important role in the spatial distribution of dengue cases during epidemics. By the end of the 21st century, if temperature increases by approximately 3°C, mean incidence rates during epidemics could double. In New Caledonia, a subtropical insular environment, both temperature and socio-economic conditions are influencing the spatial spread of dengue fever. Extension of this study to other countries worldwide should improve the knowledge about climate influence on dengue burden and about the complex interplay between different factors. This study presents a methodology that can be used as a step by step guide to model dengue spatial heterogeneity in other countries.
ISSN: 1935-2727

Droits : http://creativecommons.org/licenses/by/
pasteur-01247037
https://hal-riip.archives-ouvertes.fr/pasteur-01247037
https://hal-riip.archives-ouvertes.fr/pasteur-01247037/document
https://hal-riip.archives-ouvertes.fr/pasteur-01247037/file/journal.pntd.0004211.pdf
DOI : 10.1371/journal.pntd.0004211

Éditeur(s) : HAL CCSD Météo et Climat
Résumé : International audience
D'initiative française, le projet international HyMeX a pour objectif d'améliorer la compréhension du cycle de l'eau en Méditerranée, de sa variabilité, de l'échelle de l'événement météorologique aux échelles saisonnières et interannuelles, et de ses caractéristiques sur une décennie, dans un contexte de changement global. Le projet est motivé par le rôle déterminant des processus de mésoéchelle, couplés entre l'atmosphère, la mer et la terre, sur la variabilité du système climatique et sur le déclenchement d'événements hydrométéorologiques extrêmes (précipitations et inondations, vents forts et convection océanique, canicules et sécheresses). Le projet vise enfin à évaluer les conséquences de ces événements extrêmes sur la vulnérabilité sociale et économique de cette région et sa capacité d'adaptation.
ISSN: 0026-1181

hal-00828758
https://hal.archives-ouvertes.fr/hal-00828758
https://hal.archives-ouvertes.fr/hal-00828758/document
https://hal.archives-ouvertes.fr/hal-00828758/file/meteo_2013_80_23%20%281%29.pdf
DOI : 10.4267/2042/48792

Éditeur(s) : HAL CCSD Météo et Climat
Résumé : International audience
Les risques hydrométéorologiques sont au coeur du programme de recherche HyMeX sur le cycle de l'eau en Méditerranée. HyMeX a pour ambition d'améliorer leur prévision, de mieux connaître leur variabilité à l'échelle pluriannuelle et de renseigner sur leur évolution, dans le contexte du changement climatique. À cette fin, deux campagnes de mesures dédiées à ces événements extrêmes (SOP1 : pluies intenses et crues rapides ; SOP2 : vents forts et formation d'eaux denses) sont organisées en Méditerranée nord-occidentale, entre septembre 2012 et mars 2013.
ISSN: 0026-1181

hal-00829760
https://hal.archives-ouvertes.fr/hal-00829760
DOI : 10.4267/2042/48793

Éditeur(s) : HAL CCSD Nature Publishing Group
Résumé : International audience
Seabirds concentrate nutrients from large marine areas on their nesting islands playing an important ecological role in nutrient transfer between marine and terrestrial ecosystems. Here we investigate the role of guano on corals reefs across scales by analyzing the stable nitrogen isotopic (delta N-15) values of the scleractinian coral Pocillopora damicornis on fringing reefs around two Pacific remote islets with large seabird colonies. Marine stations closest to the seabird colonies had higher nitrate + nitrite concentrations compared to more distant stations. Coral and zooxanthellae delta N-15 values were also higher at these sites, suggesting that guano-derived nitrogen is assimilated into corals and contributes to their nitrogen requirements. The spatial extent of guano influence was however restricted to a local scale. Our results demonstrate that seabird-derived nutrients not only spread across the terrestrial ecosystem, but also affect components of the adjacent marine ecosystem. Further studies are now needed to assess if this nutrient input has a positive or negative effect for corals. Such studies on remote islets also open fresh perspectives to understand how nutrients affect coral reefs isolated from other anthropogenic stressors.
ISSN: 2045-2322

hal-01681575
https://hal.archives-ouvertes.fr/hal-01681575
DOI : 10.1038/s41598-017-03781-y

Éditeur(s) : HAL CCSD Royal Meteorological Society
Résumé : Assessing the impact/adaptation of human activities on/to climate change is a key issue, especially in the tropics that concentrate major anthropogenic dynamics such as deforestation and nearly two-thirds of the planetary rainfall. However, this task is often made tough because human activities such as agricultural dynamics are usually analysed at local or regional scale whereas climate related studies are led at large to global scales due to a lack of reliable data, especially in the tropics. In this article we argue that the increased spatial resolution of remote sensing-based rainfall estimates enables assessing the spatiotemporal variability of rainfall regimes at regional and local scales, thus allowing fine analysis of the interactions with human activities. We processed Tropical Rainfall Measuring Mission (TRMM) 3B42 daily rainfall estimates over the state of Mato Grosso (southern Brazilian Amazon) for the 1998-2012 study period in order to compute rainfall metrics such as annual rainfall and duration, onset and end dates of the rainy season based on the Anomalous Accumulation methodology (at a 0.25◦ spatial resolution). We then crossed these metrics with agricultural maps (produced at a 250m spatial resolution) and proved that the adoption of intensive agricultural practices such as double cropping systems is partly the result of a strategy to adapt practices to local climatic conditions. Finally, we discuss how such results raise important issues regarding the sustainability of the agricultural development model in the Southern Amazon.
International Journal of Climatology

halshs-00910825
https://halshs.archives-ouvertes.fr/halshs-00910825
DOI : 10.1002/joc.3863

Éditeur(s) : HAL CCSD
Résumé : National audience
We propose a method to solve the problem of clustering individuals described by mixed variables structured in blocks. It is a hierarchical method with two levels similar to Hierarchical Principal Component Analysis presented by Wold, based on the mixed topology maps (MTM). The first step consists in establishing, for each block of mixed variables, a clustering representing a synthesis of local individuals at the block level. The second step is to re-apply MTM on the weighted results of the first level. We obtain a global clustering of individuals, consensus among the partitions from level 1. The proposed method is illustrated on data from the national survey in the French housing stock carried out in 2003-2005 by the Observatory for Indoor Air Quality (OQAI).
Fouille de Données Complexes, complexité liée aux données multiples et massives (FDC)
bordeaux, France

hal-00748841
https://hal.archives-ouvertes.fr/hal-00748841
https://hal.archives-ouvertes.fr/hal-00748841/document

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Until recently, our ability to implement and assess spatial marine management approaches has been limited by a lack of information regarding processes that bind marine ecosystems, including habitat locations, larval and adult movement, trophic interactions, and fisher behavior. However, recent advances in habitat-mapping technologies, genetics, marine microchemistry, animal tracking and numerical modeling have greatly enhanced our knowledge of these processes. Although these advances have yet to be fully integrated into management decisions, they have the potential to revolutionize spatial marine management. Nevertheless, this revolution will require advances in our ability to share and integrate data into models of marine ecosystems.
ISSN: 1877-3435

hal-00609464
https://hal.archives-ouvertes.fr/hal-00609464
DOI : 10.1016/j.cosust.2010.02.002

Éditeur(s) : HAL CCSD
Résumé : International audience
Until recently, our ability to implement and assess spatial marine management approaches has been limited by a lack of information regarding processes that bind marine ecosystems, including habitat locations, larval and adult movement, trophic interactions, and fisher behavior. However, recent advances in habitat-mapping technologies, genetics, marine microchemistry, animal tracking and numerical modeling have greatly enhanced our knowledge of these processes. Although these advances have yet to be fully integrated into management decisions, they have the potential to revolutionize spatial marine management. Nevertheless, this revolution will require advances in our ability to share and integrate data into models of marine ecosystems.
Current opinion in environmental sustainability

hal-00473438
https://hal.archives-ouvertes.fr/hal-00473438
DOI : 10.1016/j.cosust.2010.02.002