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4. Rebuilding Mediterranean marine resources under climate change

Author

Moullec, F, Barrier, N., Guilhaumon, F., Peck, M.A., Ulses, C., Shin, Y.J., Moullec, F, Barrier, N., Guilhaumon, F., Peck, M.A., Ulses, C., and Shin, Y.J.

Abstract

The Mediterranean Sea ranks among the most overexploited and fastest-warming ocean regions. This situation calls for urgent development of global change scenarios and models of marine biodiversity to anticipate changes and support ecosystem-based management strategies across the entire Mediterranean Sea. Using a new end-to-end modelling chain for the whole Mediterranean Sea, we explored the potential effects of changes in fishing pressure on marine resources and ecosystem structure and functioning under a worst-case climate change scenario (RCP8.5). We found that a decrease in fishing mortality or an improvement in fishing selectivity could increase the total biomass and total catch of high trophic level species by the middle and end of the 21st century, especially the biomass of demersal, large pelagic and benthic species, thereby reversing the projected climate-induced decrease in their biomass and catch by the end of the century in the western Mediterranean basin. In contrast, climate change could offer opportunities for some eastern Mediterranean fisheries to increase catches of thermophilic and/or exotic species benefiting from new favourable environmental conditions. Based on a suite of ecological indicators, our results indicated clear positive effects of a more sustainable fisheries management on ecosystem structure and functioning. However, a decrease in fishing pressure may not fully compensate for climate-induced changes on marine resources and ecosystems, but rather buffer some projected negative impacts. Our study highlights the need for a more sustainable exploitation of fisheries resources to restore marine ecosystems and increase their resilience in a global change context.

Published
2023

8. Marine ecosystems’ responses to climatic and anthropogenic forcings in the Mediterranean

Author

Durrieu de Madron, X., Guieu, C., Sempéré, R., Conan, P., Cossa, D., D’Ortenzio, F., Estournel, C., Gazeau, F., Rabouille, C., Stemmann, L., Bonnet, S., Diaz, F., Koubbi, P., Radakovitch, O., Babin, M., Baklouti, M., Bancon-Montigny, C., Belviso, S., Bensoussan, N., Bonsang, B., Bouloubassi, I., Brunet, C., Cadiou, J.-F., Carlotti, F., Chami, M., Charmasson, S., Charrière, B., Dachs, J., Doxaran, D., Dutay, J.-C., Elbaz-Poulichet, F., Eléaume, M., Eyrolles, F., Fernandez, C., Fowler, S., Francour, P., Gaertner, J.C., Galzin, R., Gasparini, S., Ghiglione, J.-F., Gonzalez, J.-L., Goyet, C., Guidi, L., Guizien, K., Heimbürger, L.-E., Jacquet, S.H.M., Jeffrey, W.H., Joux, F., Le Hir, P., Leblanc, K., Lefèvre, D., Lejeusne, C., Lemé, R., Loÿe-Pilot, M.-D., Mallet, M., Méjanelle, L., Mélin, F., Mellon, C., Mérigot, B., Merle, P.-L., Migon, C., Miller, W.L., Mortier, L., Mostajir, B., Mousseau, L., Moutin, T., Para, J., Pérez, T., Petrenko, A., Poggiale, J.-C., Prieur, L., Pujo-Pay, M., Pulido-Villena, Raimbault, P., Rees, A.P., Ridame, C., Rontani, J.-F., Ruiz Pino, D., Sicre, M.A., Taillandier, V., Tamburini, C., Tanaka, T., Taupier-Letage, I., Tedetti, M., Testor, P., Thébault, H., Thouvenin, B., Touratier, F., Tronczynski, J., Ulses, C., Van Wambeke, F., Vantrepotte, V., Vaz, S., and Verney, R.

Published
2011
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10. Amélioration de la gestion des conditions de frontières ouvertes biogéochimiques dans les modèles physiques et biogéochimiques couplés régionaux afin de reproduire les principaux processus d’échanges côte - large. Action vers une Modélisation Intégrée Côtière Opérationnelle (AMICO)

Author

Pinazo, Christel, Ross, Oliver, Diaz, F., Doglioli, A.m., D'Ortenzio, F., Estournel, C., Forget, P., Garnier, Valerie, Gutknecht, E., Kersale, M., Kessouri, F., Lathuilière, C., Marie, Louis, Marmain, J., Marsaleix, P., Perruche, C., Petrenko, A., Reffray, G., Sourisseau, Marc, Taillandier, V., Taupier-letage, I., Testor, P., Thouvenin, Benedicte, Ulses, C., and Eldin, G.

Published
2015

13. Assessment of the amount of Cesium-137 released into the Pacific Ocean after the Fukushima accident and analysis of its dispersion in Japanese coastal waters

Author

Estournel, C., Bosc, E., Bocquet, M., Ulses, C., Marsaleix, P., Winiarek, V., Osvath, I., Nguyen, C., Duhaut, T., Lyard, F., MICHAUD, H., Auclair, F., Laboratoire d'aérologie (LAERO), Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Environment Laboratories (IAEA), International Atomic Energy Agency [Vienna] (IAEA), Centre d'Enseignement et de Recherche en Environnement Atmosphérique (CEREA), École des Ponts ParisTech (ENPC)-EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Coupling environmental data and simulation models for software integration (Clime), Inria Paris-Rocquencourt, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Echanges Côte-Large (ECOLA), Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'aérologie (LA), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Institut d’Électronique, de Microélectronique et de Nanotechnologie (IEMN) - UMR 8520 (IEMN), Ecole Centrale de Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université Paul-Valéry - Montpellier 3 (UPVM), Université de Toulouse (UT)-Université de Toulouse (UT)-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 de Recherche pour le Développement (IRD)-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), 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 de Recherche pour le Développement (IRD)-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 de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Université Polytechnique Hauts-de-France (UPHF)-Ecole Centrale de Lille-Université Polytechnique Hauts-de-France (UPHF)-Institut supérieur de l'électronique et du numérique (ISEN), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), and Université Paul-Valéry - Montpellier 3 (UM3)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)

Subjects
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, inverse method, [SDU]Sciences of the Universe [physics], cesium, numerical modelling, nuclear accident, Fukushima, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, ComputingMilieux_MISCELLANEOUS
Abstract

International audience; Numerical modeling was used to provide a new estimate of the amount of 137Cs released directly into the ocean from the Fukushima Daiichi nuclear power plant (NPP) after the accident in March 2011 and to gain insights into the physical processes that led to its dispersion in the marine environment during the months following the accident. An inverse method was used to determine the time-dependent 137Cs input responsible for the concentrations observed at the NPP's two liquid discharge outlets. The method was then validated through comparisons of the simulated concentrations with concentrations measured in seawater at different points in the neighborhood of the plant. An underestimation was noticed for stations located 30 km offshore. The resulting bias in the release inventory was estimated. Finally, the maximum 137Cs activity released directly to the ocean was estimated to lie between 5.1 and 5.5 PBq (Peta Becquerel = 1015 Bq) but uncertainties remain on the amount of radionuclides released during the first few days after the accident. This estimate was compared to previous ones and differences were analyzed further. The temporal and spatial variations of the 137Cs concentration present in the coastal waters were shown to be strongly related to the wind intensity and direction. During the first month after the accident, winds blowing toward the south confined the radionuclides directly released into the ocean to a narrow coastal band. Afterwards, frequent northward wind events increased the dispersion over the whole continental shelf, leading to strongly reduced concentrations.

Published
2012

14. Marine ecosystems'responses to climatic and anthropogenic forcings in the Mediterranean

Author

Durrieu de Madron, X., Guieu, C., Sempéré, R., Conan, P., Cossa, D., D'Ortenzio, F., Estournel, C., Gazeau, F., Rabouille, C., Stemmann, L., Bonnet, Sophie, Diaz, Frédéric, Koubbi, P., Radakovitch, O., Babin, M., Baklouti, M., Bancon-Montigny, C., Belviso, S., Bensoussan, N., Bonsang, B., Bouloubassi, I., Brunet, C., Cadiou, J.F., Carlotti, F., Chami, M., Charmasson, S., Charrière, B., Dachs, J., Doxaran, D., Dutay, J.C., Elbaz Poulichet, F., Eléaume, M., Eyrolles, F., Fernandez, C., Fowler, S., Francour, P., Gaertner, J.C., Galzin, R., Gasparini, S., Ghiglione, J.F., Gonzalez, J.L., Goyet, C., Guidi, L., Guizien, K., Heimbürger, L.E., Jacquet, S.H.M., Jeffrey, W.H., Joux, F., Le Hir, P., Leblanc, K., Lefèvre, D., Lejeusne, C., Lemé, R., Loÿe-Pilot, M.D., Mallet, M., Méjanelle, L., Mélin, F., Mellon, C., Mérigot, B., Merle, P.L., Migon, C., Miller, W.L., Mortier, L., Mostajir, B., Mousseau, L., Moutin, T., Para, J., Pérez, T., Petrenko, A., Poggiale, J.C., Prieur, L., Pujo-Pay, M., Pulido-Villena, Raimbault, P., Rees, A.P., Ridame, C., Rontani, J.F., Ruiz Pino, D., Sicre, M.A., Taillandier, V., Tamburini, C., Tanaka, T., Taupier-Lepage, I., Tedetti, M., Testor, P., Thébault, H., Thouveni, B., Touratier, F., Tronczynski, J., Ulses, C., Van Wambeke, F., Vantrepotte, V., Vaz, S., and Verney, R.

Subjects
CIRCULATION OCEANIQUE, PHYTOPLANCTON, ALTERATION, ZOOPLANCTON, FONCTIONNEMENT DE L'ECOSYSTEME, SEL NUTRITIF, RADIATION SOLAIRE, TEMPERATURE, FACTEUR ANTHROPIQUE, CYCLE BIOGEOCHIMIQUE, ACIDIFICATION, IMPACT SUR L'ENVIRONNEMENT
Published
2011

16. Dense shelf water cascading in the northwestern Mediterranean during the cold winter 2005: Quantification of the export through the Gulf of Lion and the Catalan margin

Author

Ulses, C., Estournel, C., Puig, P., Durrieu de Madron, X., Marsaleix, P., Laboratoire d'aérologie (LAERO), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP), 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)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-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), Institute of Marine Sciences / Institut de Ciències del Mar [Barcelona] (ICM), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Centre de formation et de recherche sur l'environnement marin (CEFREM), Université de Perpignan Via Domitia (UPVD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Ecosystems Studies, Laboratoire d'aérologie (LA), Centre de Formation et de Recherche sur les Environnements Méditérranéens (CEFREM), and Université de Perpignan Via Domitia (UPVD)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], [SDU]Sciences of the Universe [physics], Mediterranean Sea, Dense shelf water cascading, ComputingMilieux_MISCELLANEOUS, dense shelf water cascading
Abstract

6 pages, 3 figures, Dense shelf water cascading in the northwestern Mediterranean Sea during winter 2005, which was shown to cause large erosion in the canyons and to influence deep benthic ecosystem, was investigated using numerical modeling validated with temperature and current observations. Intense dense water formation took place on the Gulf of Lion and Catalan shelves. Dense shelf water was transferred to the deep basin through three pathways. The Cap de Creus canyon in the western Gulf of Lion already identified as a huge pathway was shown to export about 1000 km3 of dense water during two months. The Palamós and Blanes canyons located on the Catalan margin were shown to be important pathways for water formed locally and for water transiting from the Gulf of Lion. After the cascading period, dense shelf water was transported mostly toward the Balearic Sea, The moorings in the Cap de Creus canyon were funded by the US Office of Naval Research (ONR Grant N00014-04-1-0379). This study was supported by the EU Eurostrataform project and by CNRS INSU through the LEFE-IDAO program

Published
2008

17. Modeling biogeochemical processes in sediments from the Rhone River prodelta area (NW Mediterranean Sea)

Author

Pastor, L., Cathalot, C., Deflandre, B., Viollier, E., Soetaert, K., Meysman, F. J. R., Ulses, C., Metzger, E., Rabouille, C., Pastor, L., Cathalot, C., Deflandre, B., Viollier, E., Soetaert, K., Meysman, F. J. R., Ulses, C., Metzger, E., and Rabouille, C.

Abstract

In situ oxygen microprofiles, sediment organic carbon content, and pore-water concentrations of nitrate, ammonium, iron, manganese, and sulfides obtained in sediments from the Rhone River prodelta and its adjacent continental shelf were used to constrain a numerical diagenetic model. Results showed that (1) the organic matter from the Rhone River is composed of a fraction of fresh material associated to high first-order degradation rate constants (11-33 yr(-1)); (2) the burial efficiency (burial/input ratio) in the Rh boolean AND one prodelta (within 3 km of the river outlet) can be up to 80 %, and decreases to similar to 20% on the adjacent continental shelf 10-15 km further offshore; (3) there is a large contribution of anoxic processes to total mineralization in sediments near the river mouth, certainly due to large inputs of fresh organic material combined with high sedimentation rates; (4) diagenetic by-products originally produced during anoxic organic matter mineralization are almost entirely precipitated (> 97 %) and buried in the sediment, which leads to (5) a low contribution of the re-oxidation of reduced products to total oxygen consumption. Consequently, total carbon mineralization rates as based on oxygen consumption rates and using Redfield stoichiometry can be largely underestimated in such River-dominated Ocean Margins (RiOMar) environments.

Published
2011
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18. Functioning of the planktonic ecosystem on the Gulf of Lions shelf (NW Mediterranean) during spring and its impact on the carbon deposition: a field data and 3-D modelling combined approach

Author

Auger, Pierre-amael, Diaz, F., Ulses, C., Estournel, Claude, Neveux, J., Joux, F., Pujo-pay, M., Naudin, J. J., Auger, Pierre-amael, Diaz, F., Ulses, C., Estournel, Claude, Neveux, J., Joux, F., Pujo-pay, M., and Naudin, J. J.

Abstract

A coupled hydrodynamic-biogeochemical modelling is developed to address main mechanisms that drive the particulate organic carbon (POC) deposition in the Gulf of Lions (NW-Mediterranean). Low-salinity water (LSW, salinity < 37.5) lenses detached from the Rhone River plume under specific wind conditions tend to favour the biological productivity and provide a good opportunity for validating a planktonic ecosystem modelling. A specific calibration dedicated to river plume ecosystems is then proposed and validated using in situ measurements within such LSW lens (BIOPRHOFI cruise - May 2006) and on the Gulf of Lions. During spring 2006, the POC deposition is maximal on the prodelta area and within the coastal area in the Gulf of Lions. Organic detritus mostly contribute to the total POC deposition (82-92 %) whereas the contribution of living organisms (microphytoplankton) appears lower than 17 %. Exploring both influences of terrestrial inputs from the Rhone River and planktonic ecosystems on the POC deposition on the shelf, we estimated that the contribution of terrestrial POM inputs to the total POC deposition is lower than 17% at the shelf scale during the study period, with maxima during peak discharges of the Rhone River. The main deposition area of terrestrial POC is found in the vicinity of the river mouth in agreement with sediment data. On the other hand, a remarkable influence of marine biological processes on the POC deposition is highlighted further on the shelf (from 60 to 80m depth). A tight feedback between zooplankton and POM contents in the water column is proposed to explain the control of POC deposition by zooplankton: terrestrial POM inputs would favour the development of living organisms through photosynthesis and grazing processes increasing the retention of organic matter within the food web. By favouring the development of large-sized zooplankton, LSW lenses may have paradoxically a negative impact on the carbon deposition on the shelf. In the sa

Published
2011
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19. Impact of natural (waves and currents) and anthropogenic (trawl) resuspension on the export of particulate matter to the open ocean Application to the Gulf of Lion (NW Mediterranean)

Author

Ferre, B, Durrieu De Madron, X, Estournel, C, Ulses, C, Le Corre, Gildas, Ferre, B, Durrieu De Madron, X, Estournel, C, Ulses, C, and Le Corre, Gildas

Abstract

Modern sediment deposits on continental margins form a vast reservoir of particulate matter that is regularly affected by resuspension processes. Resuspension by bottom trawling on shelves with strong fishing activity can modify the scale of natural disturbance by waves and currents. Recent field data show that the impact of bottom trawls on fine sediment resuspension per unit surface is comparable with that of the largest storms. We assessed the impact of both natural and anthropogenic processes on the dispersal of riverborne particles and shelf sediments on the Gulf of Lion shelf. We performed realistic numerical simulations of resuspension and transport forced by currents and waves or by a fleet of bottom trawlers. Simulations were conducted for a 16-month period (January 1998-April 1999) to characterise the seasonal variability. The sediment dynamics takes into account bed armoring, ripple geometry and the cohesive and non-cohesive characteristics of the sediments. Essential but uncertain parameters (clay content, erosion fluxes and critical shear stress for cohesive sediment) were set with existing data. Resuspension by waves and currents was controlled by shear stress, whereas resuspension by trawls was controlled by density and distribution of the bottom trawler fleet. Natural resuspension by waves and currents mostly occurred during short seasonal episodes, and was concentrated on the inner shelf. Trawling-induced resuspension, in contrast, occurred regularly throughout the year and was concentrated on the outer shelf. The total annual erosion by trawls (5.6 x 10(6) t y(-1), t for metric tonnes) was four orders of magnitude lower than the erosion induced by waves and currents (35.3 x 10(9) t y(-1)). However the net resuspension (erosion/deposition budget) for trawling (0.4 x 10(6) t y(-1)) was only one order of magnitude lower than that for waves and currents (9.2 x 10(6) t y(-1)). Off-shelf export concerned the finest fraction of the sediment (clays and fin

Published
2008
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20. Suspended sediment transport in the Gulf of Lions (NW Mediterranean): Impact of extreme storms and floods

Author

Ulses, C., Estournel, C., Durrieu de Madron, X., Palanques, A., Ulses, C., Estournel, C., Durrieu de Madron, X., and Palanques, A.

Abstract

In situ observations were combined with 3D modeling to gain understanding of and to quantify the suspended sediment transport in the Gulf of Lions (NW Mediterranean Sea). The outputs of a hydrodynamic–sediment transport coupled model were compared to near-bottom current and suspended sediment concentration measurements collected at the head of seven submarine canyons and at a shallow shelf site, over a 6-month period (November 2003–May 2004). The comparisons provide a reasonable validation of the model that reproduces the observed spatial and time variations. The study period was marked by an unusual occurrence of marine storms and high river inputs. The major water and sediment discharges were supplied by the Rhone, the largest Mediterranean river, during an exceptional flood accompanying a severe marine storm in early December 2003. A second major storm, with moderate flooding, occurred in February 2004. The estimate of river input during the studied period was 5.9 Mt. Our study reveals (i) that most of the particulate matter delivered by the Rhone was entrapped on the prodelta, and (ii) that marine storms played a crucial role on the sediment dispersal on the shelf and the off-shelf export. The marine storms occurring in early December 2003 and late February 2004 resuspended a very large amount of shelf sediment (>8 Mt). Erosion was controlled by waves on the inner shelf and by energetic currents on the outer shelf. Sediment deposition took place in the middle part of the shelf, between 50 and 100 m depth. Resuspended sediments and river-borne particles were transported to the southwestern end of the shelf by a cyclonic circulation induced by these onshore winds and exported towards the Catalan shelf and into the Cap de Creus Canyon which incises the slope close to the shore. Export taking place mostly during marine storms was estimated to reach 9.1 Mt during the study period., In situ observations were combined with 3D modeling to gain understanding of and to quantify the suspended sediment transport in the Gulf of Lions (NW Mediterranean Sea). The outputs of a hydrodynamic–sediment transport coupled model were compared to near-bottom current and suspended sediment concentration measurements collected at the head of seven submarine canyons and at a shallow shelf site, over a 6-month period (November 2003–May 2004). The comparisons provide a reasonable validation of the model that reproduces the observed spatial and time variations. The study period was marked by an unusual occurrence of marine storms and high river inputs. The major water and sediment discharges were supplied by the Rhone, the largest Mediterranean river, during an exceptional flood accompanying a severe marine storm in early December 2003. A second major storm, with moderate flooding, occurred in February 2004. The estimate of river input during the studied period was 5.9 Mt. Our study reveals (i) that most of the particulate matter delivered by the Rhone was entrapped on the prodelta, and (ii) that marine storms played a crucial role on the sediment dispersal on the shelf and the off-shelf export. The marine storms occurring in early December 2003 and late February 2004 resuspended a very large amount of shelf sediment (>8 Mt). Erosion was controlled by waves on the inner shelf and by energetic currents on the outer shelf. Sediment deposition took place in the middle part of the shelf, between 50 and 100 m depth. Resuspended sediments and river-borne particles were transported to the southwestern end of the shelf by a cyclonic circulation induced by these onshore winds and exported towards the Catalan shelf and into the Cap de Creus Canyon which incises the slope close to the shore. Export taking place mostly during marine storms was estimated to reach 9.1 Mt during the study period.

Published
2008

21. Assessment of the amount of cesium-137 released into the Pacific Ocean after the Fukushima accident and analysis of its dispersion in Japanese coastal waters

Author

Estournel, C., primary, Bosc, E., additional, Bocquet, M., additional, Ulses, C., additional, Marsaleix, P., additional, Winiarek, V., additional, Osvath, I., additional, Nguyen, C., additional, Duhaut, T., additional, Lyard, F., additional, Michaud, H., additional, and Auclair, F., additional

Published
2012
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29. Functioning of the planktonic ecosystem of the Rhone River plume (NW Mediterranean) during spring and its impact on the carbon export: a field data and 3-D modelling combined approach.

Author

Auger, P. A., Diaz, F., Ulses, C., Estournel, C., Neveux, J., Joux, F., Pujo-Pay, M., and Naudin, J. J.

Subjects
PLANKTON, BIOTIC communities, HYDRODYNAMICS, BIOLOGICAL productivity, PARTICULATE matter
Abstract

Low-salinity water (LSW, Salinity<37.5) lenses detached from the Rhone River plume under specific wind conditions tend to favour the biological productivity and potentially a transfer of energy to higher trophic levels on the Gulf of Lions (GoL). A field cruise conducted in May 2006 (BIOPRHOFI) followed some LSW lenses by using a lagrangian strategy. A thorough analysis of the available data set enabled to further improve our understanding of the LSW lenses' functioning and their potential influence on marine ecosystems. Through an innovative 3-D coupled hydrodynamic-biogeochemical modelling approach, a specific calibration dedicated to river plume ecosystems was then proposed and validated on field data. Exploring the role of ecosystems on the particulate organic carbon (POC) export and deposition on the shelf, a sensitivity analysis to the particulate organic matter inputs from the Rhone River was carried out from 1 April to 15 July 2006. Over such a typical end-of-spring period marked by moderate floods, the main deposition area of POC was identified alongshore between 0 and 50m depth on the GoL, extending the Rhone prodelta to the west towards the exit of the shelf. Moreover, the main deposition area of terrestrial POC was found on the prodelta region, which confirms recent results from sediment data. The averaged daily deposition of particulate organic carbon over the whole GoL is estimated by the model between 40 and 80 mgC/m², which is in the range of previous secular estimations. The role 20 of ecosystems on the POC export toward sediments or offshore areas was actually highlighted and feedbacks between ecosystems and particulate organic matters are proposed to explain paradoxical model results to the sensitivity test. In fact, the conversion of organic matter in living organisms would increase the retention of organic matter in the food web and this matter transfer along the food web could explain the 25 minor quantity of POC of marine origin observed in the shelf sediments. Thus, the effective carbon deposition on the shelf might be strongly dependent on the zooplankton presence in the GoL. Owing to their fertilizing ability in phosphorus, the LSW lenses could then have indirectly a negative impact on the carbon deposition on the shelf by favouring the development of large phytoplankton fuelling in turn zooplankton communities. The effective carbon deposition would then be delayed out of the GoL, unless a novel transfer of matter occurs toward higher trophic levels further in the open sea through small pelagic fishes. [ABSTRACT FROM AUTHOR]

Published
2010
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30. Corrigendum to “Marine ecosystems’ responses to climatic and anthropogenic forcings in the Mediterranean” [Prog. Oceanogr. 91 (2011) 97–166]

Author

Durrieu de Madron, X., Guieu, C., Sempéré, R., Conan, P., Cossa, D., D’Ortenzio, F., Estournel, C., Gazeau, F., Rabouille, C., Stemmann, L., Bonnet, S., Diaz, F., Koubbi, P., Radakovitch, O., Babin, M., Baklouti, M., Bancon-Montigny, C., Belviso, S., Bensoussan, N., Bonsang, B., Bouloubassi, I., Brunet, C., Cadiou, J.-F., Carlotti, F., Chami, M., Charmasson, S., Charrière, B., Dachs, J., Doxaran, D., Dutay, J.-C., Elbaz-Poulichet, F., Eléaume, M., Eyrolles, F., Fernandez, C., Fowler, S., Francour, P., Gaertner, J.C., Galzin, R., Gasparini, S., Ghiglione, J.-F., Gonzalez, J.-L., Goyet, C., Guidi, L., Guizien, K., Heimbürger, L.-E., Jacquet, S.H.M., Jeffrey, W.H., Joux, F., Le Hir, P., Leblanc, K., Lefèvre, D., Lejeusne, C., Lemé, R., Loÿe-Pilot, M.-D., Mallet, M., Méjanelle, L., Mélin, F., Mellon, C., Mérigot, B., Merle, P.-L., Migon, C., Miller, W.L., Mortier, L., Mostajir, B., Mousseau, L., Moutin, T., Para, J., Pérez, T., Petrenko, A., Poggiale, J.-C., Prieur, L., Pujo-Pay, M., Pulido-Villena, Raimbault, P., Rees, A.P., Ridame, C., Rontani, J.-F., Ruiz Pino, D., Sicre, M.A., Taillandier, V., Tamburini, C., Tanaka, T., Taupier-Letage, I., Tedetti, M., Testor, P., Thébault, H., Thouvenin, B., Touratier, F., Tronczynski, J., Ulses, C., Van Wambeke, F., Vantrepotte, V., Vaz, S., and Verney, R.

Published
2011
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31. Predictive Factors for Patients' Failure to Show for Initial Outpatient Physical Therapist Evaluation.

Author

Briggs MS, Ulses C, VanEtten L, Mansfield C, Ganim A, Hand BN, and Quatman-Yates CC

Subjects
Adult, Ambulatory Care, Female, Humans, Male, Middle Aged, Retrospective Studies, No-Show Patients statistics & numerical data, Physical Therapy Modalities
Abstract

Objective: The objective of this study was to examine primary factors that may predict patients' failure to show at initial physical therapist evaluation in an orthopedic and sports outpatient setting., Methods: A retrospective analysis of patients' demographic data for physical therapist evaluations between January 2013 and April 2015 was performed. A binary logistic regression model was used to evaluate the odds of a no-show at evaluation. Demographic variables of age, employment status, days waited for the appointment, payer source, and distance traveled to the clinic were analyzed. Independent variables were considered significant if the 95% CIs of the odds ratios (ORs) did not include 1.0., Results: A total of 6971 patients were included in the final analysis, with 10% (n = 698) of the scheduled patients having a no-show event for their initial evaluation. The following factors increased the odds of patients having a no-show event: days to appointment (OR = 1.058; 95% CI = 1.042-1.074), unemployment status (OR = 1.96; 95% CI = 1.41-2.73), unknown employment status (OR = 3.22; 95% CI = 1.12-8.69), Medicaid insurance (OR = 4.87; 95% CI = 3.43-6.93), Medicare insurance (OR = 2.22; 95% CI = 1.10-4.49), unknown payer source (OR = 262.84; 95% CI = 188.72-366.08), and distance traveled 8 or more kilometers (OR = 1.31; 95% CI = 1.01-1.70). Female sex (OR = 0.73; 95% CI = 0.57-0.95) and age 40 years or older (OR = 0.44; 95% CI = 0.33-0.60) decreased the odds of a no-show event., Conclusions: Results from this study indicate there may be some demographic factors that are predictive of patients failing to attend their first physical therapist visit., Impact: Understanding the predictive factors and identifying potential opportunities for improvements in scheduling processes might help decrease the number of patients failing to show for their initial physical therapy appointment, with the ultimate goal of positively influencing patient outcomes., (© The Author(s) 2021. Published by Oxford University Press on behalf of the American Physical Therapy Association. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Published
2021
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