330 results on '"Ulses, C."'
Search Results
2. A non-hydrostatic non-Boussinesq algorithm for free-surface ocean modelling
- Author
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Auclair, F., Bordois, L., Dossmann, Y., Duhaut, T., Paci, A., Ulses, C., and Nguyen, C.
- Published
- 2018
- Full Text
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3. Rebuilding Mediterranean marine resources under climate change
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Moullec, F, primary, Barrier, N, additional, Guilhaumon, F, additional, Peck, MA, additional, Ulses, C, additional, and Shin, YJ, additional
- Published
- 2023
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4. Predictive Factors for Patients' Failure to Show for Initial Outpatient Physical Therapist Evaluation.
- Author
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Briggs MS, Ulses C, VanEtten L, Mansfield C, Ganim A, Hand BN, and Quatman-Yates CC
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- 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.)
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- 2021
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5. 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)
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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
6. From source to sink: part 1-characterization and Lagrangian tracking of riverine microplastics in the Mediterranean Basin.
- Author
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Weiss L, Estournel C, Marsaleix P, Mikolajczak G, Constant M, and Ludwig W
- Abstract
The Mediterranean Sea is one of the most critically polluted areas due to its semi-enclosed structure and its highly anthropized shoreline. Rivers are significant vectors for pollutant transfers from the continental to the marine environment. In this context, a 3D Lagrangian simulation of the dispersion of riverine microplastics (MPs) was performed, which included the application of a recently developed model that reassessed the MP fluxes discharged by rivers. MP physical properties from river samples were further investigated to approximate vertical displacement in modeled ocean currents. The use of a high-resolution circulation model, integrating Stokes drift, turbulent diffusion, and MP sinking and rising velocities, enabled us to establish stock balances. Our simulation suggested that 65% of river inputs may be made of floating MPs drifting in the surface layer and 35% of dense MPs sinking to deeper layers. The Eastern Mediterranean tends to accumulate floating MPs, primarily originating from the Western Mediterranean Basin, where major river sources are concentrated. After 2 years of simulation, modeled stranding sequestered 90% of the MP inputs, indicating relatively short average residence times from a few days to months at most for particles at sea. Although spatial distribution patterns stabilized after this period and a steady state may have been approached, the surface concentrations we modeled generally remained below field observations. This suggested either an underestimation of sources (rivers and unaccounted sources), by a factor of 6 at most, or an overestimation of MP withdrawal through stranding, to be reduced from 90 to around 60% or less if unaccounted sinks were considered., (© 2024. The Author(s).)
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- 2024
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7. Budget of organic carbon in the North- Western Mediterranean open sea over the period 2004-2008 using 3-D coupled physical-biogeochemical modeling.
- Author
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Ulses, C., Auger, P.-A., Soetaert, K., Marsaleix, P., Diaz, F., Coppola, L., Herrmann, M.J., Kessouri, F., and Estournel, C.
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- 2016
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8. Influence of environmental variability and age on the body condition of small pelagic fish in the Gulf of Lions
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Brosset, P, primary, Ménard, F, additional, Fromentin, JM, additional, Bonhommeau, S, additional, Ulses, C, additional, Bourdeix, JH, additional, Bigot, JL, additional, Van Beveren, E, additional, Roos, D, additional, and Saraux, C, additional
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- 2015
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9. Significant challenges to the sustainability of the California coast considering climate change.
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Thorne, Karen M., MacDonald, Glen M., Chavez, Francisco P., Ambrose, Richard F., and Barnard, Patrick L.
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COASTAL zone management ,MARINE heatwaves ,COASTAL changes ,ABSOLUTE sea level change ,COASTS - Abstract
Climate change is an existential threat to the environmental and socioeconomic sustainability of the coastal zone and impacts will be complex and widespread. Evidence from California and across the United States shows that climate change is impacting coastal communities and challenging managers with a plethora of stressors already present. Widespread action could be taken that would sustain California's coastal ecosystems and communities. In this perspective, we highlight the main threat to coastal sustainability: the compound effects of episodic events amplified with ongoing climate change, which will present unprecedented challenges to the state. We present two key challenges for California's sustainability in the coastal zone: 1) accelerating sea-level rise combined with storm impacts, and 2) continued warming of the oceans and marine heatwaves. Cascading effects from these types of compounding events will occur within the context of an already stressed system that has experienced extensive alterations due to intensive development, resource extraction and harvesting, spatial containment, and other human use pressures. There are critical components that could be used to address these immediate concerns, including comanagement strategies that include diverse groups and organizations, strategic planning integrated across large areas, rapid implementation of solutions, and a cohesive and policy relevant research agenda for the California coast. Much of this has been started in the state, but the scale could be increased, and timelines accelerated. The ideas and information presented here are intended to help expand discussions to sharpen the focus on how to encourage sustainability of California's iconic coastal region. [ABSTRACT FROM AUTHOR]
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- 2024
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10. Implementation of a brittle sea ice rheology in an Eulerian, finite-difference, C-grid modeling framework: impact on the simulated deformation of sea ice in the Arctic.
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Brodeau, Laurent, Rampal, Pierre, Ólason, Einar, and Dansereau, Véronique
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STRAINS & stresses (Mechanics) ,SPATIAL resolution ,MODELS & modelmaking ,RHEOLOGY ,VELOCITY ,SEA ice - Abstract
We have implemented the brittle Bingham–Maxwell sea ice rheology (BBM) into SI3, the sea ice component of NEMO. After discussing the numerical aspects and requirements that are specific to the implementation of a brittle rheology in the Eulerian, finite-difference, Arakawa C-grid framework, we detail the approach we have used. This approach relies on the introduction of an additional set of prognostic stress tensor components, sea ice damage, and sea ice velocity vector, following a grid point arrangement that expands the C-grid into the Arakawa E-grid. The newly implemented BBM rheology is first assessed by means of a set of idealized SI3 simulations at different spatial resolutions. Then, sea ice deformation rates obtained from simulations of the Arctic at a 1/4 ° spatial resolution, performed with the coupled ocean–sea ice setup of NEMO, are assessed against satellite observations. For all these simulations, results obtained with the default current workhorse setup of SI3 are provided to serve as a reference. Our results show that using a brittle type of rheology, such as BBM, allows SI3 to simulate the highly localized deformation pattern of sea ice, as well as its scaling properties, from the scale of the model's computational grid up to the basin scale. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Implementation and assessment of a model including mixotrophs and the carbonate cycle (Eco3M_MIX-CarbOx v1.0) in a highly dynamic Mediterranean coastal environment (Bay of Marseille, France) – Part 2: Towards a better representation of total alkalinity when modeling the carbonate system and air–sea CO2 fluxes
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Barré, Lucille, Diaz, Frédéric, Wagener, Thibaut, Mazoyer, Camille, Yohia, Christophe, and Pinazo, Christel
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CARBON dioxide ,ALKALINITY ,SEAWATER ,SALINITY ,OCEAN - Abstract
The Bay of Marseille (BoM), located in the northwestern Mediterranean Sea, is affected by various hydrodynamic processes (e.g., Rhône River intrusion and upwelling events) that result in a highly complex local carbonate system. In any complex environment, the use of models is advantageous since it allows us to identify the different environmental forcings, thereby facilitating a better understanding. By combining approaches from two biogeochemical ocean models and improving the formulation of total alkalinity, we develop a more realistic representation of the carbonate system variables at high temporal resolution, which enables us to study air–sea CO 2 fluxes and seawater p CO 2 variations more reliably. We apply this new formulation to two particular scenarios that are typical for the BoM: (i) summer upwelling and (ii) Rhône River intrusion events. In both scenarios, our model was able to correctly reproduce the observed patterns of p CO 2 variability. Summer upwelling events are typically associated with a p CO 2 decrease that mainly results from decreasing near-surface temperatures. Furthermore, Rhône River intrusion events are typically associated with a p CO 2 decrease, although, in this case, the p CO 2 decrease results from a decrease in salinity and an overall increase in total alkalinity. While we were able to correctly represent the daily range of air–sea CO 2 fluxes, the present configuration of Eco3M_MIX-CarbOx does not allow us to correctly reproduce the annual cycle of air–sea CO 2 fluxes observed in the area. This pattern directly impacts our estimates of the overall yearly air–sea CO 2 flux as, even if the model clearly identifies the bay as a CO 2 sink, its magnitude was underestimated, which may be an indication of the limitations inherent in dimensionless models for representing air–sea CO 2 fluxes. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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12. Demersal fishery Impacts on Sedimentary Organic Matter (DISOM): a global harmonized database of studies assessing the impacts of demersal fisheries on sediment biogeochemistry.
- Author
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Paradis, Sarah, Tiano, Justin, De Borger, Emil, Pusceddu, Antonio, Bradshaw, Clare, Ennas, Claudia, Morys, Claudia, and Sciberras, Marija
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DREDGING (Fisheries) ,MARINE sediments ,DATABASES ,GEOGRAPHICAL distribution of fishes ,RESEARCH personnel - Abstract
Marine sediments are among the largest carbon reservoirs on the planet and play a key role in the global cycling of organic matter. Bottom fisheries are the most widespread anthropogenic physical disturbance to seabed habitats, prompting NGOs and governments to act on regulating mobile bottom-contacting fishing gear. However, the scientific evidence of the effects of bottom trawling on sediment biogeochemistry is highly diverse and presents contrasting results. Here we present a global harmonized dataset of 71 independent studies that assess the effects of demersal fisheries on sedimentological (i.e. grain size, porosity) and biogeochemical (i.e. organic carbon, phytopigments, nutrient fluxes) properties: the Demersal fishery Impacts on Sedimentary Organic Matter (DISOM) database (Paradis, 2023; 10.3929/ethz-b-000634336). We identify considerable gaps, namely in the geographical extension of the data; coverage of environmental predictors (i.e. seasons); fishing descriptors such as the availability of true controls, quantification of fishing effort, and distribution of fishing gear types; and biogeochemical variables that study the remineralization of organic matter. Future studies should address these data gaps to enhance the comprehensiveness of the dataset. With this harmonized database, we aim to allow researchers to explore the effects of demersal fisheries in variable environmental settings to disentangle the effects of this disturbance and provide efficient management strategies. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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13. Rapid Restratification Processes Control Mixed Layer Turbulence and Phytoplankton Growth in a Deep Convection Region.
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Miracca‐Lage, Mariana, Becherer, Johannes, Merckelbach, Lucas, Bosse, Anthony, Testor, Pierre, and Carpenter, Jeffrey R.
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TURBULENCE ,OCEAN turbulence ,TURBULENT mixing ,PHYTOPLANKTON ,OCEAN waves ,SPRING - Abstract
The Gulf of Lion, Northwestern Mediterranean Sea, is one of few oceanic regions where deep convection occurs. We investigate the restratification following a convection event using measurements from an ocean glider equipped with turbulence microstructure sensors. This unique combination of instruments provides a high‐resolution description of the mixed layer with regard to turbulence, stratification and chlorophyll. We observe a rapid restratification process that proceeds over a timescale of days to one week. We find that restratification exerts a leading order control on surface mixed layer turbulence variability, as abrupt changes in turbulence dissipation rates are associated with the formation of near‐surface stratification. The near‐surface formation of stratification occurs through both the diurnal variability in surface buoyancy fluxes and through lateral advective processes. We conclude that daily near‐surface processes that influence stratification control mixed layer turbulence levels, and thus the phytoplankton response in the critical transition period to spring bloom. Plain Language Summary: During winter in the Gulf of Lion, Northwestern Mediterranean Sea, a unique alignment of ocean conditions allow strong winds to cool the ocean surface enough to cause mixing of the surface waters to great depths in a process known as deep convection. When this event ceases, the water column tends to restore its original configuration, with light waters above dense waters. We capture the onset of this process, known as restratification, in high‐resolution observational detail together with measurements of ocean turbulence levels, collected with an autonomous ocean vehicle. The onset of restratification after convection takes place on a timescale of days to one week, and strongly influences turbulence variations within the surface waters. We conclude that this restratification has two main contributors, the near‐surface stratification that forms due to the daily variation of surface buoyancy fluxes, and the lateral exchange of denser waters from the surroundings. With sufficient light and nutrients after convection, this near‐surface stratification together with the absence of turbulent mixing allow phytoplankton to grow. Key Points: Autonomous glider‐based turbulence measurements have captured restratification in a deep convection regionThe onset of restratification occurs rapidly, over a timescale of days to one weekNear‐surface restratification is a primary control on mixed layer turbulence and phytoplankton growth [ABSTRACT FROM AUTHOR]
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- 2024
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14. Optimal Duration of Physical Therapy Following Total Knee Arthroplasty.
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Benes, Gregory, Adams, Zachary, Dubic, Michael, David, Justin, Leonardi, Claudia, Bronstone, Amy, and Dasa, Vinod
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PHYSICAL therapy ,MEDICAL care use ,GERIATRICS ,LOGISTIC regression analysis ,TREATMENT duration ,RETROSPECTIVE studies ,CHI-squared test ,MULTIVARIATE analysis ,PHYSICAL medicine ,TOTAL knee replacement ,MEDICAL records ,ACQUISITION of data ,PLASTIC surgery ,RANGE of motion of joints - Abstract
Aims & Objectives: The purpose of this study was to identify patient characteristics associated with engagement and completion of physical therapy (PT) following total knee arthroplasty (TKA) and examine the relationship between number of PT sessions attended and outcomes during the first 12 weeks after surgery. Methods: Patients underwent unilateral primary TKA by a single surgeon and were advised to complete 17 PT sessions over 6 weeks at a hospital-affiliated facility. Analyses examined predictors of PT engagement (attendance of ≥2 sessions) and completion (attendance of 17 ± 1 sessions) within 6 weeks and associations between number of PT sessions attended and changes in range of motion (ROM) and Knee Injury and Osteoarthritis Outcome Score (KOOS) values. Results: Patients living <40 km were more likely to be engaged in PT than those living ≥40 km from the clinic (P <.0001). Among patients who completed PT within 6 weeks, 95.0%, 85.1%, and 56.4% achieved flexion of, respectively, ≥90°, ≥100°, and ≥110°. Among engaged patients, the active flexion thresholds of ≥90°, ≥100°, and ≥110° were achieved by, respectively, 94.4%, 82.5%, and 58.1% by 6 weeks and by 96.7%, 92.1%, and 84.2% by 12 weeks. Improvement in KOOS Symptoms (P =.029), Function in daily living (P =.030) and quality of life (P =.031) linearly decreased as number of PT sessions increased. Conclusions: These results raise the question of whether patients who meet satisfactory outcomes before completing 6 weeks of prescribed PT and those who attend more PT sessions than prescribed may be over-utilizing healthcare resources without additional benefit. [ABSTRACT FROM AUTHOR]
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- 2024
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15. Comparison of the Coastal and Regional Ocean COmmunity model (CROCO) and NCAR-LES in non-hydrostatic simulations.
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Fan, Xiaoyu, Fox-Kemper, Baylor, Suzuki, Nobuhiro, Li, Qing, Marchesiello, Patrick, Sullivan, Peter P., and Hall, Paul S.
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SPEED of sound ,OCEAN ,TURBULENCE ,VISCOSITY ,LARGE eddy simulation models - Abstract
Advances in coastal modeling and computation provide the opportunity to examine non-hydrostatic and compressible fluid effects at very small scales, but the cost of these new capabilities and the accuracy of these models versus trusted non-hydrostatic codes has yet to be determined. Here the Coastal and Regional Ocean COmmunity model (CROCO, v1.2) and the National Center for Atmospheric Research large-eddy simulation (NCAR-LES) model are compared, with a focus on their simulation accuracy and computational efficiency. These models differ significantly in numerics and capabilities, so they are run on common classic problems of surface-forced, boundary-layer turbulence. In terms of accuracy, we compare turbulence statistics, including the effect of the explicit subgrid-scale (SGS) parameterization, the effect of the second (dilatational) viscosity, and the sensitivity to the speed of sound, which is used as part of the CROCO compressible turbulence formulation. To gauge how far CROCO is from the NCAR-LES, we first compare the NCAR-LES with two other non-hydrostatic Boussinesq approximation LES codes (PALM and Oceananigans), defining the notion and magnitude of accuracy for the LES and CROCO comparison. To judge efficiency of CROCO, strong and weak scaling simulation sets vary different problem sizes and workloads per processor, respectively. Additionally, the effects of 2D decomposition of CROCO and NCAR-LES and supercomputer settings are tested. In summary, the accuracy comparison between CROCO and the NCAR-LES is similar to the NCAR-LES compared to other LES codes. However, the additional capabilities of CROCO (e.g., nesting, non-uniform grid, and realism of ocean configuration in general) and its weakly compressible formulation come with roughly an order of magnitude of additional costs, despite efforts to reduce them by adjusting the second viscosity and speed of sound as far as accuracy allows. However, a new variant of the non-hydrostatic CROCO formulation is currently undergoing prototype testing and should enable faster simulations by releasing the stability constrain by the free surface. Overall, when the additional features of CROCO are needed (nesting, complex topography, etc.) additional costs are justified, while in idealized settings (a rectangular domain with periodic boundary conditions) the NCAR-LES is faster in arriving at nearly the same result. [ABSTRACT FROM AUTHOR]
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- 2024
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16. Biogeographical and seasonal distribution of pteropod populations in the western and central Mediterranean Sea inferred from sediment traps.
- Author
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Béjard, Thibauld M., Manno, Clara, Sierro, Francisco J., Flores, José-Abel, Tarruella, Javier P., de Madron, Xavier Durrieu, Sanchez-Vidal, Anna, and Rigual-Hernández, Andrés S.
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OCEAN temperature ,ANTHROPOGENIC effects on nature ,GEOCHEMICAL cycles ,SEDIMENTS ,AUTUMN - Abstract
Pteropods are a group of cosmopolitan holoplanktic gastropods that produce an aragonite shell and play an important role in both marine ecosystems and geochemical cycles. In addition to being affected by anthropogenic impacts that include warming and changes in carbonate system parameters, the Mediterranean Sea is considered to be understudied concerning pteropods dynamics and abundances. This work aims to document the modern spatial and temporal distributions of pteropods populations in the Northwestern and Central Mediterranean Sea (Gulf of Lions and Strait of Sicily), respectively. We present data from two sediment-trap records that cover the timeframe between early 1996 and early 2004 for the Gulf of Lions and late 2013 to late 2014 for the Sicily Strait. A total of 843 pteropod shells and 18 different species were identified. Limacina inflata, Creseis virgula and Creseis clava were the most abundant species in the Gulf of Lions, while in the Sicily Strait, C. conica replaced C. clava as the most abundant species. These taxons represented around 70% of the total individuals identified in both sites. Overall, our results suggest a greater pteropod abundance in the Gulf of Lions than in the Sicily Strait, most likely due to enhanced food conditions. In the Gulf of Lions, maximum fluxes occurred in autumn (32.5% of the annual pteropod fluxes registered in October), while in the Sicily Strait peak fluxes occurred in winter (30.5% of the annual pteropod fluxes registered in January). Comparison of temporal changes pteropod fluxes with satellite sea surface temperature (SST), and chlorophyll-a concentration suggest a possible positive effect of high algal accumulation and cool water conditions in the Strait of Sicily on the main pteropod groups. In turn, no clear relationships between pteropod groups, SST and chlorophyll-a were identified in the Gulf of Lions, highlighting the effect of salinity and carbonate system parameters. Overall, and despite the limitations associated with the use of sediment traps for pteropod population monitoring, the consistency of our results with the literature supports the use of sediment traps as useful tools for documenting the diversity and temporal distribution of pteropods. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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17. A south Mediterranean country's demand on available marine biomass: assessment of Algerian fisheries sustainability.
- Author
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Akrour, Sonia and Grimes, Samir
- Subjects
MARINE resources ,SUSTAINABILITY ,MARINE biomass ,COASTS ,FOOD security ,BIOMASS ,FISHERIES - Abstract
This study focuses on fishing activity, specifically the extraction of marine resources in the Algerian coastal and offshore zones. This sector is expected to meet several objectives and contribute to Algeria's food security. Seafood is a significant source of protein and is highly favoured by Algeria's coastal communities. However, with limited data available describing the biomass that could be exploited, the pressure could eventually increase on a common stock that is shared by all users and is already regarded as poorly studied. Against this backdrop, this work considers the estimation of the marine footprint, which is the ratio between the demand of each fished species, known as the required primary production, and the available biomass in terms of primary production of Algerian fishing waters. The latter is derived from the literature, relying on studies covering the considered area. The main study findings outline a marine footprint ratio that does not exceed 1%, demonstrating a sustainable fishing activity. However, the obtained results, i.e., low marine footprint percentage, may imply that the available marine biomass in the Algerian fishing zones is not fully exploited. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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18. Reviews and syntheses: Biological Indicators of Oxygen Stress in Water Breathing Animals.
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Roman, Michael R., Altieri, Andrew H., Breitburg, Denise, Ferrer, Erica, Gallo, Natalya D., Ito, Shin-ichi, Limburg, Karin, Rose, Kenneth, Yasuhara, Moriaki, and Levin, Lisa A.
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OXYGEN detectors ,BIOINDICATORS ,BIOSYNTHESIS ,OXYGEN in water ,AQUATIC animals ,MARINE biology ,OCEAN - Abstract
Anthropogenic warming and nutrient over-enrichment of our oceans have resulted in significant, and often catastrophic, reductions in dissolved oxygen (deoxygenation). Stress on water-breathing animals from this deoxygenation has been shown to occur at all levels of biological organization: cellular; organ; individual; species; population; community; and ecosystem. Most climate forecasts predict increases in ocean deoxygenation, thus it is essential to develop reliable biological indicators of oxygen stress that can be used by regional and global oxygen monitoring efforts to detect and assess the impacts of deoxygenation on ocean life. This review focuses on indicators of low-oxygen stress that are manifest at different levels of biological organization and at a variety of spatial and temporal scales. We compare particular attributes of these indicators to the dissolved oxygen threshold of response, time-scales of response, sensitive life stages and taxa, and the ability to scale the response to oxygen stress across levels of organization. Where there is available evidence, we discuss the interactions of other biological and abiotic stressors on the biological indicators of oxygen stress. We address the utility, confounding effects, and implementation of the biological indicators of oxygen stress for both research and societal applications. Our hope is that further refinement and dissemination of these oxygen stress indicators will provide more direct support for environmental managers, fisheries and mariculture scientists, conservation professionals, and policy makers to confront the challenges of ocean deoxygenation. An improved understanding of the sensitivity of different ocean species, communities and ecosystems to low oxygen stress will empower efforts to design monitoring programs, assess ecosystem health, develop management guidelines, track conditions, and detect low-oxygen events. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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19. Spurious numerical mixing under strong tidal forcing: a case study in the South East Asian Seas using the Symphonie model (v3.1.2).
- Author
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Garinet, Adrien, Herrmann, Marine, Marsaleix, Patrick, and Pénicaud, Juliette
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TIDAL forces (Mechanics) ,VERTICAL motion ,ADVECTION ,WATER masses - Abstract
The role of mixing between layers of different density is key to how the ocean works and interacts with other components of the Earth System. Accounting correctly for its effect in numerical simulations is therefore of utmost importance. However, numerical models are still plagued with spurious sources of mixing, originating mostly from the vertical advection schemes in the case of fixed coordinates models. As the number of phenomenon explicitly resolved by models increases, so does the amplitude of resolved vertical motions and the amount of spurious numerical mixing; and regional models are no exception to this. This papers provides a clear illustration of this phenomenon in the context of simulation of the South East Asian Seas is provided, along with a simple way to reduce it. This region is known for its particularly strong internal tides and the fundamental role they play in the dynamic of the region. Using the Symphonie ocean model, simulations including and excluding tides and using a pseudo third-order upwind advection scheme on the vertical are compared to several reference datasets, and the impact on water masses in assessed. The high diffusivity of this advection scheme is demonstrated, along with the importance of accounting for tidal mixing for a correct representation of water masses. Simultaneously, an improvement of this advection scheme to make it more suitable for use on the vertical is provided. Simulations with the new formulation are added in the comparison. We conclude that the use of a higher order numerical diffusion operator greatly improves the overall performance of the model. [ABSTRACT FROM AUTHOR]
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- 2024
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20. Cross-scale environmental impacts across persistent and dynamic aggregations within a complex population: implications for fisheries management.
- Author
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Kerametsidis, Georgios, Thorson, James, Rossi, Vincent, Álvarez-Berastegui, Diego, Barnes, Cheryl, Certain, Gregoire, Esteban, Antonio, García, Encarnación, Jadaud, Angélique, Piñeiro, Safo, Vivas, Miguel, and Hidalgo, Manuel
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FISH populations ,ORTHOGONAL functions ,SPATIAL systems ,FACTOR analysis ,FISHERY management - Abstract
Accounting for marine stocks spatiotemporal complexity has become one of the most pressing improvements that should be added to the new generation of stock assessment. Disentangling persistent and dynamic population subcomponents and understanding their main drivers of variation are still stock-specific challenges. Here, we hypothesized that the spatiotemporal variability of density in two adjacent fish stocks is associated with spatially structured environmental processes across multiple spatiotemporal scales. To test this, we applied a generalized empirical orthogonal function and dynamic factor analysis to fishery-independent and -dependent data of red mullet, a highly commercial species, in the Western Mediterranean Sea. Areas with persistent and dynamic high aggregations were detected for both stock units. A large-scale climatic index and local open-ocean convection were associated with both stocks, while other variables exhibited stock-specific effects. We also revealed spatially structured density dynamics within the examined management units. This suggests a metapopulation structure and supports the future implementation of a spatial stock assessment. Considering the common—generally unrealistic—assumptions of panmictic structure and absence of connectivity with neighbouring stock units, our methodology can be applied to other species and systems with putative spatial complexity to inform more accurate population dynamics and structure. [ABSTRACT FROM AUTHOR]
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- 2024
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21. Potential Invasiveness of Devil Firefish Pterois miles (Bennett 1828) in the Eastern Adriatic Sea.
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Bakiu, Rigers, Soldo, Alen, and Ćetković, Ilija
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PTEROIS miles ,INTRODUCED species ,ECOLOGICAL impact - Abstract
Devil firefish Pterois miles is an invasive alien species which has severely impacted biodiversity and ecological processes in invaded areas of the Mediterranean. In recent years, its presence has been documented in several countries of the Adriatic Sea. Based on the negative ecological and socio-economic impacts in other areas of the Mediterranean Sea, the potential invasiveness of devil firefish was analyzed for the coastal areas of the three eastern Adriatic countries (Albania, Croatia and Montenegro) using the Aquatic Species Invasiveness Screening Kit. Generally, based on the average value of the Basic Risk Assessment and the threshold used, the outcomes suggest that this species will be highly invasive in the eastern Adriatic countries. In addition, the results have shown that the most affected sector is represented by the local species populations and relative characteristics, while commercial sectors represent the least affected sector. However, considering that the negative impact of non-native species is not seen directly, the governments of these countries should address this issue as soon as possible. [ABSTRACT FROM AUTHOR]
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- 2024
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22. A nonhydrostatic formulation for MPAS-Ocean.
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Calandrini, Sara, Engwirda, Darren, and Roekel, Luke Van
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LARGE eddy simulation models ,INTERNAL waves ,ATMOSPHERIC models ,BOUSSINESQ equations - Abstract
The Model for Prediction Across Scales-Ocean (MPAS-Ocean) is an open-source, global ocean model and is one component of a family of climate models within the MPAS framework, including atmosphere, sea-ice, and land-ice models. In this work, a new formulation for the ocean model is presented that solves the nonhydrostatic, incompressible Boussinesq equations on an unstructured, staggered, z-level grid. The introduction of this nonhydrostatic capability is necessary for the resolution of internal wave dynamics and large eddy simulations. Compared to the standard, hydrostatic formulation, a nonhydrostatic pressure solver and a vertical momentum equation are added, where the PETSc (Portable Extensible Toolkit for Scientific Computation) library is used for the inversion of a large sparse system for the nonhydrostatic pressure. Numerical results on a stratified seiche, internal solitary wave, overflow and lock-exchange test cases are presented, and the parallel efficiency of the code is evaluated using up to 128 processors. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
23. Mechanisms and intraseasonal variability of the South Vietnam Upwelling, South China Sea: role of circulation, tides and rivers.
- Author
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Herrmann, Marine and Duy, Thai To
- Subjects
TIDAL currents ,CONTINENTAL shelf ,TOPOGRAPHY ,ADVECTION - Abstract
Summer monsoon southwest wind induces the South Vietnam Upwelling (SVU) over four main areas along the southern and central Vietnamese coast: offshore the Mekong shelf (MKU), along the Southern and Northern coasts (SCU and NCU) and offshore (OFU). Previous studies have highlighted the roles of wind and Ocean Intrinsic Variability (OIV) in the SVU intraseasonal to interannual variability. The present study complements these results by examining the influence of tides and river discharges and investigating the physical mechanisms involved in MKU functioning. MKU is driven by non chaotic processes, explaining its negligible intrinsic variability. It is triggered first by the interactions of currents over a marked topography. The surface convergence of currents over the southwestern slope of the Mekong shelf induces a downwelling of the warm northeastward alongshore current. It flows over the shelf and encounters a cold northwestward bottom current when reaching the northeastern slope. The associated bottom convergence and surface divergence lead to an upwelling of cold water which is entrained further north by the surface alongshore current. Tides and rivers do not modify the chronology of upwelling for the four areas. Tides do not significantly influence OFU and NCU intensity. They strengthen the circulation-topography-induced MKU through two processes. First, tidal currents weaken the current over the shallow coastal shelf by enhancing the bottom friction. This increases the horizontal velocity gradient hence the resulting surface convergence and divergence and the associated downwelling and upwelling. Second, they reinforce the surface cooling upstream and downstream the shelf through lateral and vertical tidal mixing. This tidal reinforcement explains 72 % of MKU intensity on average over the summer, and is partly transmitted to SCU through advection. River discharges do not significantly influence OFU, NCU and SCU intensity. Mekong waters slightly weaken MKU (by 9 % on the annual average) by strengthening the stratification. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
24. Microbiological and Toxicological Investigations on Bivalve Molluscs Farmed in Sicily.
- Author
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Castello, Annamaria, Alio, Vincenzina, Cammilleri, Gaetano, Sciortino, Sonia, Macaluso, Andrea, Ferrantelli, Vincenzo, Dall'Ara, Sonia, Pino, Fiorella, Servadei, Irene, Oliveri, Giuseppa, and Costa, Antonella
- Subjects
AEROMONAS hydrophila ,MOLLUSKS ,POLLUTANTS ,ESCHERICHIA coli ,METAL detectors ,VIBRIO alginolyticus ,BIVALVES - Abstract
Bivalves can concentrate biological and chemical pollutants, causing foodborne outbreaks whose occurrence is increasing, due to climatic and anthropic factors that are difficult to reverse, hence the need for improved surveillance. This study aimed to evaluate the hygienic qualities of bivalves sampled along the production and distribution chain in Sicily and collect useful data for consumer safety. Bacteriological and molecular analyses were performed on 254 samples of bivalves for the detection of enteropathogenic Vibrio, Arcobacter spp., Aeromonas spp., Salmonella spp., and beta-glucuronidase-positive Escherichia coli. A total of 96 out of 254 samples, collected in the production areas, were processed for algal biotoxins and heavy metals detection. Bacterial and algal contaminations were also assessed for 21 samples of water from aquaculture implants. Vibrio spp., Arcobacter spp., Aeromonas hydrophila, Salmonella spp., and Escherichia coli were detected in 106/254, 79/254, 12/254, 16/254, and 95/254 molluscs, respectively. A total of 10/96 bivalves tested positive for algal biotoxins, and metals were under the legal limit. V. alginolyticus, A. butzleri, and E. coli were detected in 5, 3, and 3 water samples, respectively. Alexandrium minutum, Dinophysis acuminata, Lingulodinium polyedra, and Pseudonitzschia spp. were detected in water samples collected with the biotoxin-containing molluscs. Traces of yessotoxins were detected in molluscs from water samples containing the corresponding producing algae. Despite the strict regulation by the European Commission over shellfish supply chain monitoring, our analyses highlighted the need for efficiency improvement. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
25. Improved Surface Currents from Altimeter-Derived and Sea Surface Temperature Observations: Application to the North Atlantic Ocean.
- Author
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Ciani, Daniele, Asdar, Sarah, and Buongiorno Nardelli, Bruno
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OCEAN ,OCEAN currents ,GULF Stream ,GEOSTROPHIC currents ,SURFACE reconstruction ,TIME series analysis ,OCEAN temperature - Abstract
We present a study on the ocean surface currents reconstruction by merging Level-4 (L4, gap-free) altimeter-derived geostrophic currents and satellite sea surface temperature. Building upon past studies on the multi-variate reconstruction of geostrophic currents from satellite observations, we regionalized and optimized an algorithm to improve the altimeter-derived surface circulation estimates in the North Atlantic Ocean. A ten-year-long time series (2010–2019) is presented and validated by means of in situ observations. The newly optimized algorithm allowed us to improve the currents estimate along the main axis of the Gulf Stream and in correspondence of well-known upwelling areas in the North Eastern Atlantic, with percentage improvements of around 15% compared to standard operational altimetry products. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
26. New insights into the South China Sea throughflow and water budget seasonal cycle: evaluation and analysis of a high-resolution configuration of the ocean model SYMPHONIE version 2.4.
- Author
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Trinh, Ngoc B., Herrmann, Marine, Ulses, Caroline, Marsaleix, Patrick, Duhaut, Thomas, To Duy, Thai, Estournel, Claude, and Shearman, R. Kipp
- Subjects
SEAWATER ,SURFACE dynamics ,OCEAN ,SEASONS ,WATER masses ,MERIDIONAL overturning circulation ,WATER transfer ,STRAITS - Abstract
The South China Sea throughflow (SCSTF) connects the South China Sea (SCS) with neighboring seas and oceans, transferring surface water of the global thermohaline circulation between the Pacific and Indian oceans. A configuration of the SYMPHONIE ocean model at high resolution (4 km) and including an explicit representation of tides is implemented over this region, and a simulation is analyzed over 2010–2018. Comparisons with in situ and satellite data and other available simulations at coarser resolution show the good performance of the model and the relevance of the high resolution for reproducing the spatial and temporal variability of the characteristics of surface dynamics and water masses over the SCS. The added value of an online computation of each term of the water, heat, and salt SCS budgets (surface, lateral oceanic and river fluxes, and internal variations) is also quantitatively demonstrated: important discards are obtained with offline computation, with relative biases of ∼40% for lateral oceanic inflows and outflows. The SCS water volume budget, including the SCSTF, is analyzed at climatological and seasonal scales. The SCS receives on average a 4.5 Sv yearly water volume input, mainly from the Luzon Strait. It laterally releases this water to neighboring seas, mainly to the Sulu Sea through Mindoro Strait (49 %), to the East China Sea via Taiwan Strait (28 %), and to the Java Sea through Karimata Strait (22 %). The seasonal variability of this water volume budget is driven by lateral interocean exchanges. Surface interocean exchanges, especially at Luzon Strait, are all driven by monsoon winds that favor winter southwestward flows and summer northeastward surface flows. Exchanges through Luzon Strait deep layers show a stable sandwiched structure with vertically alternating inflows and outflows. Last, differences in flux estimates induced by the use of a high-resolution model vs. a low-resolution model are quantified. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
27. Movements and spatial distribution of an endangered fish (Sciaena umbra) within a marine protected area.
- Author
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Marques, R., Brazo, A., Aspillaga, E., Zimmermann, M., Hereu, B., Saragoni, G., Mercière, A., Crec'Hriou, R., Mercader, M., Verdoit-Jarraya, M., Cadène, F., and Lenfant, Philippe
- Subjects
MARINE parks & reserves ,RARE fishes ,SCIENTIFIC knowledge ,GEOGRAPHICAL distribution of fishes ,ENDANGERED species ,HABITAT partitioning (Ecology) ,HABITAT selection - Abstract
The brown meagre (Sciaena umbra) is an endangered species, which requires specific protection measures to ensure its conservation. These measures need to be informed by high-quality scientific knowledge on their space use patterns. Here, we used acoustic telemetry to assess its seasonal movement patterns and habitat use within a marine protected area (MPA). Our results suggested that S. umbra is a highly sedentary species (home range < 1.0 km
2 ) and, therefore, the MPA is extensive enough to protect the local population. Their population was discretely distributed in two main areas within the MPA, which was likely a result of habitat segregation and density-dependent movements. The temporal variability of their movements further uncovered when and where spawning occurs (mainly, but probably not only, in the fully protected area in June) and indicated that spillover of this species is limited but still possible. Overall, we highlight the importance of MPAs in the recovery of S. umbra, we advocate the need to perpetuate the current national fishing bans and extend it to other countries in the Mediterranean region, and we emphasize that considering the fine-scale movements of S. umbra in future management actions is key to achieving a successful recovery of their populations. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
28. Characterization of the benthic biogeochemical dynamics after flood events in the Rhône River prodelta: a data–model approach.
- Author
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Ferreira, Eva, Nmor, Stanley, Viollier, Eric, Lansard, Bruno, Bombled, Bruno, Regnier, Edouard, Monvoisin, Gaël, Grenz, Christian, van Beek, Pieter, and Rabouille, Christophe
- Subjects
CARBON cycle ,SEDIMENTATION & deposition ,MINERALIZATION ,METHANE ,SEDIMENTS - Abstract
At the land–sea interface, the benthic carbon cycle is strongly influenced by the export of terrigenous particulate material across the river–ocean continuum. Episodic flood events delivering massive sedimentary materials can occur, but their short-term impact on carbon cycling is poorly understood. In this paper, we use a coupled data–model approach to estimate the temporal variations in sediment–water fluxes, biogeochemical pathways and their reaction rates during these abrupt phenomena. We studied one episodic depositional event in the vicinity of the Rhône River mouth (NW Mediterranean Sea) during the fall–winter of 2021/22. The distributions of dissolved inorganic carbon (DIC), sulfate (SO42-) and methane (CH4) were measured in sediment porewaters collected every 2 weeks before and after the deposition of a 25 cm sediment layer during the main winter flood event. Significant changes in the distribution of DIC, SO42- and CH4 concentrations were observed in the sediment porewaters. The use of an early diagenetic model (FESDIA) to calculate biogeochemical reaction rates and fluxes revealed that this type of flood event can increase the total organic carbon mineralization rate in the sediment by 75 % a few days after deposition. In this period, sulfate reduction is the main process contributing to the increase in total mineralization relative to non-flood deposition. The model predicts a short-term decrease in the DIC flux out of the sediment from 100 to 55 mmolm-2d-1 after the deposition of the new sediment layer with a longer-term increase by 4 %, therefore implying an initial internal storage of DIC in the newly deposited layer and a slow release over relaxation of the system. Furthermore, examination of the stoichiometric ratios of DIC and SO42- as well as model output over this 5-month window shows a decoupling between the two modes of sulfate reduction following the deposition – organoclastic sulfate reduction (OSR) intensified in the newly deposited layer below the sediment surface, whereas anaerobic oxidation of methane (AOM) intensified at depth below the former buried surface. The bifurcation depth of sulfate reduction pathways, i.e., the sulfate–methane transition zone (SMTZ), is shifted deeper by 25 cm in the sediment column following the flood deposition. Our findings highlight the significance of short-term transient biogeochemical processes at the seafloor and provide new insights into the benthic carbon cycle in the coastal ocean. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
29. The Variation of Plankton Community Structure in Artificial Reef Area and Adjacent Waters in Haizhou Bay.
- Author
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Gao, Shike, Shi, Yixi, Lu, Yanan, and Zhang, Shuo
- Abstract
Plankton are an important component of marine protected areas (MPAs), and its communities would require much smaller interpatch distances to ensure connection among MPAs. According to the survey from MPAs dominated by artificial reefs and adjacent waters (estuary area (EA), aquaculture area (AA), artificial reef area (ARA), natural area (NA) and comprehensive effect area (CEA)) in Haizhou Bay in spring and autumn, we analyzed phyto-zooplankton composition, abundance and biomass, and correlation with hydrologic variables to gain information about the forces that structure the plankton. The results showed that the dominant zooplankton were copepods (spring, 98.9%; autumn, 94.2%), while the phytoplankton were mainly composed of Bacillariophyta (spring, 61.8%; autumn, 95.6%). The RDA results showed that temperature, salinity and depth highly associated with the distribution and composition of plankton species among the habitats than other factors in spring; temperature, Chla and DO had the strongest influence in autumn. The zooplankton in the ARA and AA ecosystems basically contained the same species as those in other habitats, and each habitat also exhibited a relatively unique combination of plankton species. The structures of the EA zooplankton in spring and the EA phytoplankton in both seasons were much different than other habitats, which may have been caused by factors such as currents and tides. We concluded that there exists similarity of the plankton community between artificial reef area and adjacent waters, whereas the EAs may be relatively independent systems. Therefore, these interaction between plankton community should be considered when designing MPA networks, and ocean circulations should be considered more than the environmental factors. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
30. A synthesis of ocean total alkalinity and dissolved inorganic carbon measurements from 1993 to 2022: the SNAPO-CO2-v1 dataset.
- Author
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Metzl, Nicolas, Fin, Jonathan, Lo Monaco, Claire, Mignon, Claude, Alliouane, Samir, Antoine, David, Bourdin, Guillaume, Boutin, Jacqueline, Bozec, Yann, Conan, Pascal, Coppola, Laurent, Diaz, Frédéric, Douville, Eric, Durrieu de Madron, Xavier, Gattuso, Jean-Pierre, Gazeau, Frédéric, Golbol, Melek, Lansard, Bruno, Lefèvre, Dominique, and Lefèvre, Nathalie
- Subjects
CARBON cycle ,OCEAN ,ALKALINITY ,OCEAN acidification ,POTENTIOMETRY ,COASTS - Abstract
Total alkalinity (AT) and dissolved inorganic carbon (CT) in the oceans are important properties with respect to understanding the ocean carbon cycle and its link to global change (ocean carbon sinks and sources, ocean acidification) and ultimately finding carbon-based solutions or mitigation procedures (marine carbon removal). We present a database of more than 44 400 AT and CT observations along with basic ancillary data (spatiotemporal location, depth, temperature and salinity) from various ocean regions obtained, mainly in the framework of French projects, since 1993. This includes both surface and water column data acquired in the open ocean, coastal zones and in the Mediterranean Sea and either from time series or dedicated one-off cruises. Most AT and CT data in this synthesis were measured from discrete samples using the same closed-cell potentiometric titration calibrated with Certified Reference Material, with an overall accuracy of ±4 µ mol kg -1 for both AT and CT. The data are provided in two separate datasets – for the Global Ocean and the Mediterranean Sea (10.17882/95414, Metzl et al., 2023), respectively – that offer a direct use for regional or global purposes, e.g., AT –salinity relationships, long-term CT estimates, and constraint and validation of diagnostic CT and AT reconstructed fields or ocean carbon and coupled climate–carbon models simulations as well as data derived from Biogeochemical-Argo (BGC-Argo) floats. When associated with other properties, these data can also be used to calculate pH, the fugacity of CO 2 (f CO 2) and other carbon system properties to derive ocean acidification rates or air–sea CO 2 fluxes. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
31. Anchovy and sardine condition and energy content in the North Aegean Sea (eastern Mediterranean) in relation to their contrasting reproductive strategies.
- Author
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Schismenou E, Chatzifotis S, Tsiaras K, and Somarakis S
- Abstract
Forage species with high biomass, such as anchovies and sardines, play a key role in pelagic ecosystems and make up a significant proportion of the world's capture fisheries production. In recent years, condition indices have gained interest as significant indicators for assessing the effects of environmental and human pressures on these species and the quality of their habitats. In the present study, we examined, for the first time in the North Aegean Sea (eastern Mediterranean), the year-round variation in somatic and gonadal condition, energy density, and percentage of lipid content of anchovy (Engraulis encrasicolus) and sardine (Sardina pilchardus). Energy density was measured with bomb calorimetry and percentage lipid content with the fatmeter, a portable electronic device. Finally, the monthly changes in gonadal and energetic condition were examined in relation to the annual cycle of temperature and mesozooplankton biomass, simulated by the implementation of a coupled hydrodynamic-biogeochemical model (POM-ERSEM). There was a strong relationship between fish energy density (kJ g
-1 ) and percentage dry weight. Furthermore, the mean monthly energy density and fatmeter measurements were strongly correlated, especially in sardine. Overall, the monthly changes in energetic condition were indicative of the species' different strategies for energy acquisition and allocation to reproduction (capital vs. income breeding): sardine exhibited low energy density and percentage lipid content during the winter spawning period (November-March) and markedly higher energetic condition from spring to autumn (April-October). Anchovy spawning period, as inferred from gonadal condition, lasted from April to September, i.e., during the warm period of the year but its energy density and percentage lipid content did not exhibit any seasonal changes and were markedly lower than in sardine from April to October. Finally, the simulated mesozooplankton biomass was higher from January to July, which corresponded to the second half of the spawning season for sardine, but first half of the spawning season for anchovy., (© 2024 The Author(s). Journal of Fish Biology published by John Wiley & Sons Ltd on behalf of Fisheries Society of the British Isles.)- Published
- 2024
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- View/download PDF
32. Elemental Composition and Health Risk Assessment of Deep-Sea Teleost's of the Levantine Basin.
- Author
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Çiftçi N and Ayas D
- Abstract
The determination of metal(loid) (As, Fe, Al, Sr, Zn, Pb, Mn, Cu, Cr, and Cd) levels in the muscle tissue of 23 different deep-sea bony fish sampled off Mersin Bay (NE Levantine Basin) and the assessment of health risks for human consumption were aimed. Tissue metal(loid) concentrations were determined as dry weight and analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The tissue metal(loid) concentrations (µg g dw) were converted to wet weight prior to health risk assessment calculations. Standard mathematical formulas were used to determine the health risk assessment. There was a statistically significant difference between the fish species in terms of tissue metal(loid) levels (p < 0.05). The highest metal(loid) level was found in C. sloani among other species. As and Fe had the highest and Cd the lowest tissue concentrations in the examined species (p < 0.05). The relationships between the metal(loid)s analyzed in the tissue were significant (p < 0.01;0.05). Fe had an antagonistic effect with Cd, while other metal(loid)s had a synergetic effect with each other. Risk assessment analyses were performed for the consumable species, and it was found that the estimated daily and weekly intakes were below the tolerable limits established by the Food and Agriculture Organization (FAO) and the World Health Organization (WHO). The target hazard quotient (THQ) values exceeded the threshold of 1 (THQ > 1) only for As. The target cancer risk (TCR) was below the tolerable limits (> 10
-5 ) except for As, Cd, and Al., (© 2024. The Author(s).)- Published
- 2024
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- View/download PDF
33. Identifying factors associated with physical therapy use versus non-use among injured workers with back pain in Washington State.
- Author
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Chin B, Rundell SD, Sears JM, Fulton-Kehoe D, Spector JT, and Franklin GM
- Subjects
- Humans, Washington, Male, Female, Adult, Middle Aged, Logistic Models, Occupational Diseases epidemiology, Occupational Diseases therapy, Back Injuries epidemiology, Workers' Compensation statistics & numerical data, Occupational Injuries epidemiology, Physical Therapy Modalities statistics & numerical data, Back Pain epidemiology
- Abstract
Background: There is little information about predictors of physical therapy (PT) use among injured workers with back pain. The primary objective of this study is to investigate the associations between PT use and baseline factors not routinely captured in workers' compensation (WC) data., Methods: We conducted a secondary analysis using the Washington State Workers' Compensation Disability Risk Identification Study Cohort, which combines self-reported surveys with claims data from the Washington State Department of Labor and Industries State Fund. Workers with an accepted or provisional WC claim for back injury between June 2002 and April 2004 were eligible. Baseline factors for PT use were selected from six domains (socio-demographic, pain and function, psychosocial, clinical, health behaviors, and employment-related). The outcome was a binary measure for PT use within 1 year of injury. Bivariate and multivariable logistic regression models were conducted to evaluate the associations between PT use and baseline factors., Results: Among the 1370 eligible study participants, we identified 673 (49%) who received at least one PT service. Baseline factors from five of the six domains (all but health behaviors) were associated with PT use, including gender, income, pain and function measures, injury severity rating, catastrophizing, recovery expectations, fear avoidance, mental health score, body mass index, first provider seen for injury, previous injury, and several work-related factors., Conclusion: We identify baseline factors that are associated with PT use, which may be useful in addressing disparities in access to care for injured workers with back pain in a WC system., (© 2024 Wiley Periodicals LLC.)
- Published
- 2024
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- View/download PDF
34. Observing the full ocean volume using Deep Argo floats.
- Author
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Zilberman, Nathalie V., Thierry, Virginie, King, Brian, Alford, Matthew, André, Xavier, Balem, Kevin, Briggs, Nathan, Zhaohui Chen, Cabanes, Cécile, Coppola, Laurent, Dall'Olmo, Giorgio, Desbruyères, Damien, Fernandez, Denise, Foppert, Annie, Gardner, Wilford, Gasparin, Florent, Hally, Bryan, Shigeki Hosoda, Johnson, Gregory C., and Kobayashi, Taiyo
- Subjects
GLOBAL warming ,OCEANIC mixing ,LIGHT scattering ,ENTHALPY ,FRESH water ,DISSOLVED oxygen in water ,OCEAN ,OCEAN color - Abstract
The ocean is the main heat reservoir in Earth's climate system, absorbing most of the top-of-the-atmosphere excess radiation. As the climate warms, anomalously warm and fresh ocean waters in the densest layers formed near Antarctica spread northward through the abyssal ocean, while successions of warming and cooling events are seen in the deep-ocean layers formed near Greenland. The abyssal warming and freshening expands the ocean volume and raises sea level. While temperature and salinity characteristics and large-scale circulation of upper 2000 m ocean waters are well monitored, the present ocean observing network is limited by sparse sampling of the deep ocean below 2000 m. Recently developed autonomous robotic platforms, Deep Argo floats, collect profiles from the surface to the seafloor. These instruments supplement satellite, Core Argo float, and ship-based observations to measure heat and freshwater content in the full ocean volume and close the sea level budget. Here, the value of Deep Argo and planned strategy to implement the global array are described. Additional objectives of Deep Argo may include dissolved oxygen measurements, and testing of ocean mixing and optical scattering sensors. The development of an emerging ocean bathymetry dataset using Deep Argo measurements is also described. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
35. A climate modeling study over Northern Africa and the Mediterranean basin with multi-physics ensemble and coupling to a regional ocean modeling system.
- Author
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Fengyi Xie, Chandan, Deepak, Peltier, W. Richard, and Hadjinicolaou, Panos
- Subjects
ATMOSPHERIC models ,ATMOSPHERIC boundary layer ,GENERAL circulation model ,OCEAN temperature ,METEOROLOGICAL research - Abstract
We have developed a physics ensemble of Weather Research and Forecasting (WRF) model simulations for the Middle East, Mediterranean and North Africa (MEMNA) regions. These simulations use different configurations for the cumulus, microphysics, surface layer, planetary boundary layer, and land surface schemes and are forced by the Community Earth System Model (CESM) General Circulation Model for the historical period 1979-1993. We have also created a complementary ensemble in which the WRF model is fully-coupled to the Regional Ocean Modelling System (ROMS) that simulates the dynamics of the entire Mediterranean Sea. Analysis of our ensembles reveals that the simulated precipitation and near surface temperature (T2) fields in WRF are largely influenced by the cumulus and the land surface schemes during the summer and winter seasons, respectively. The coupling of Weather Research and Forecasting to Regional Ocean Modelling System yields Mediterranean sea surface temperatures that are directly correlated with T2 and have higher spatial resolution than the global model. Meanwhile no significant difference is found between the atmospheric fields from the coupled and uncoupled runs because the Community Earth System Model sea surface temperatures over the Mediterranean, that are used for surface forcing in the uncoupled runs, are already in close agreement with both Regional Ocean Modelling System and observations. We conclude that our high-resolution coupled atmosphere-ocean modelling system is capable of producing climate data of good quality, and we identify those combinations of physics schemes that result in an acceptable level of bias that facilitates their use in future studies. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
36. Assessing seasonal and interannual changes in carbonate chemistry across two time-series sites in the North Western Mediterranean Sea.
- Author
-
Wimart-Rousseau, Cathy, Wagener, Thibaut, Bosse, Anthony, Raimbault, Patrick, Coppola, Laurent, Fourrier, Marine, Ulses, Caroline, and Lefèvre, Dominique
- Subjects
WATER masses ,MIXING height (Atmospheric chemistry) ,PARTIAL pressure ,SEASONS ,CARBONATES ,ADVECTION ,NO-tillage - Abstract
Sustained time-series measurements are crucial to understand changes in oceanic carbonate chemistry. In the North Western Mediterranean Sea, the temporal evolution of the carbonate system is here investigated based on two 10-year time-series (between January 2010 and December 2019) of monthly carbonate parameters measurements at two sampling sites in the Ligurian Sea (ANTARES and DYFAMED). At seasonal timescale, the seawater partial pressure of CO
2 (pCO2 ) within the mixed layer is mostly driven by temperature at both sites, and biological processes as stated by the observed relationships between total inorganic carbon (CT), nitrate and temperature. This study suggests also that mixing and water masses advection could play a role in modulating the CT content. At decadal timescale, significant changes in ocean chemistry are observed with increasing trends in CT (+3.2 ± 0.9 µmol.kg-1 .a-1 - ANTARES; +1.6 ± 0.8 µmol.kg-1 .a-1 - DYFAMED), associated with increasing pCO2 trends and decreasing trends in pH. The magnitude of the increasing trend in CT at DYFAMED is consistent with the increase in atmospheric pCO2 and the anthropogenic carbon transport of water originating from the Atlantic Ocean, while the higher trends observed at the ANTARES site could be related to the hydrological variability induced by the variability of the Northern Current. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
37. Morphological diversity increases with decreasing resources along a zooplankton time series.
- Author
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Beck, Miriam, Cailleton, Caroline, Guidi, Lionel, Desnos, Corinne, Jalabert, Laetitia, Elineau, Amanda, Stemmann, Lars, Ayata, Sakina-Dorothée, and Irisson, Jean-Olivier
- Subjects
ZOOPLANKTON ,MARINE zooplankton ,BODY size - Abstract
Biodiversity is studied notably because of its reciprocal relationship with ecosystem functions such as production. Diversity is traditionally described from a taxonomic, genetic or functional point of view but the diversity in organism morphology is seldom explicitly considered, except for body size. We describe morphological diversity of marine zooplankton seasonally and over 12 years using quantitative imaging of weekly plankton samples, in the northwestern Mediterranean Sea. We extract 45 morphological features on greater than 800 000 individuals, which we summarize into four main morphological traits (size, transparency, circularity and shape complexity). In this morphological space, we define objective morphological groups and, from those, compute morphological diversity indices (richness, evenness and divergence) using metrics originally defined for functional diversity. On both time scales, morphological diversity increased when nutritive resources and plankton concentrations were low, thus matching the theoretical reciprocal relationship. Over the long term at least, this diversity increase was not fully attributable to taxonomic diversity changes. The decline in the most common plankton forms and the increase in morphological variance and in extreme morphologies suggest a mechanism akin to specialization under low production, with likely consequences for trophic structure and carbon flux. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
38. Seasonal dynamics and annual budget of dissolved inorganic carbon in the northwestern Mediterranean deep-convection region.
- Author
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Ulses, Caroline, Estournel, Claude, Marsaleix, Patrick, Soetaert, Karline, Fourrier, Marine, Coppola, Laurent, Lefèvre, Dominique, Touratier, Franck, Goyet, Catherine, Guglielmi, Véronique, Kessouri, Fayçal, Testor, Pierre, and Durrieu de Madron, Xavier
- Subjects
ATMOSPHERIC carbon dioxide ,ALGAL blooms ,BIOGEOCHEMICAL cycles ,CARBON dioxide ,WATER masses ,SEASONS - Abstract
Deep convection plays a key role in the circulation, thermodynamics, and biogeochemical cycles in the Mediterranean Sea, which is considered to be a hotspot of biodiversity and climate change. In the framework of the DEWEX (Dense Water Experiment) project, the seasonal and annual budgets of dissolved inorganic carbon in the deep-convection area of the northwestern Mediterranean Sea are investigated over the period September 2012–September 2013 using a 3D coupled physical–biogeochemical–chemical modeling approach. At the annual scale, we estimate that the northwestern Mediterranean Sea's deep-convection region was a moderate sink of 0.5 mol C m -2 yr -1 of CO 2 for the atmosphere. The model results show the reduction of oceanic CO 2 uptake during deep convection and its increase during the abrupt spring phytoplankton bloom following the deep-convection events. We highlight the major roles in the annual dissolved inorganic carbon budget of both the biogeochemical and physical fluxes, which amount to -3.7 and 3.3 mol C m -2 yr -1 , respectively, and are 1 order of magnitude higher than the air–sea CO 2 flux. The upper layer (from the surface to 150 m depth) of the northwestern deep-convection region gained dissolved inorganic carbon through vertical physical transport and, to a lesser extent, oceanic CO 2 uptake, and it lost dissolved inorganic carbon through lateral transport and biogeochemical fluxes. The region, covering 2.5 % of the Mediterranean, acted as a source of dissolved inorganic carbon for the surface and intermediate water masses of the Balearic Sea and southwestern Mediterranean Sea and could represent up to 22 % and 11 %, respectively, of the CO 2 exchanges with the Atlantic Ocean at the Strait of Gibraltar. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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39. Chromophoric dissolved organic matter dynamics revealed through the optimization of an optical–biogeochemical model in the northwestern Mediterranean Sea.
- Author
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Álvarez, Eva, Cossarini, Gianpiero, Teruzzi, Anna, Bruggeman, Jorn, Bolding, Karsten, Ciavatta, Stefano, Vellucci, Vincenzo, D'Ortenzio, Fabrizio, Antoine, David, and Lazzari, Paolo
- Subjects
ORGANIC compounds ,OCEAN turbulence ,ABSORPTION coefficients ,SPRING ,LIGHT transmission ,OCEAN color - Abstract
Chromophoric dissolved organic matter (CDOM) significantly contributes to the non-water absorption budget in the Mediterranean Sea. The absorption coefficient of CDOM, aCDOM(λ) , is measurable in situ and can be retrieved remotely, although ocean-colour algorithms do not distinguish it from the absorption of detritus. These observations can be used as indicators for the concentration of other relevant biogeochemical variables in the ocean, e.g. dissolved organic carbon. However, our ability to model the biogeochemical processes that determine CDOM concentrations is still limited. Here we propose a novel parameterization of the CDOM cycle that accounts for the interplay between the light- and nutrient-dependent dynamics of local CDOM production and degradation, as well as its vertical transport. The parameterization is included in a one-dimensional (1D) configuration of the Biogeochemical Flux Model (BFM), which is here coupled to the General Ocean Turbulence Model (GOTM) through the Framework for Aquatic Biogeochemical Models (FABM). Here the BFM is augmented with a bio-optical component that resolves spectrally the underwater light transmission. We run this new GOTM-(FABM)-BFM configuration to simulate the seasonal aCDOM(λ) cycle at the deep-water site of the Bouée pour l'acquisition de Séries Optiques à Long Terme (BOUSSOLE) project in the northwestern Mediterranean Sea. Our results show that accounting for both nutrient and light dependence of CDOM production improves the simulation of the seasonal and vertical dynamics of aCDOM(λ) , including a subsurface maximum that forms in spring and progressively intensifies in summer. Furthermore, the model consistently reproduces the higher-than-average concentrations of CDOM per unit chlorophyll concentration observed at BOUSSOLE. The configuration, outputs, and sensitivity analyses from this 1D model application will be instrumental for future applications of BFM to the entire Mediterranean Sea in a three-dimensional configuration. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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- View/download PDF
40. Implementation and assessment of a model including mixotrophs and the carbonate cycle (Eco3M_MIX-CarbOx v1.0) in a highly dynamic Mediterranean coastal environment (Bay of Marseille, France) – Part 1: Evolution of ecosystem composition under limited light and nutrient conditions
- Author
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Barré, Lucille, Diaz, Frédéric, Wagener, Thibaut, Van Wambeke, France, Mazoyer, Camille, Yohia, Christophe, and Pinazo, Christel
- Subjects
ECOSYSTEMS ,FOOD chains ,NUTRIENT cycles ,CARBON cycle ,HETEROTROPHIC bacteria ,ZOOPLANKTON ,PROTISTA ,BIOMASS - Abstract
Many current biogeochemical models rely on an autotrophic versus heterotrophic food web representation. However, in recent years, an increasing number of studies have begun to challenge this approach. Several authors have highlighted the importance of protists capable of combining photoautotrophic and heterotrophic nutrition in a single cell. These mixotrophic protists are known to play an important role in the carbon cycle. Here, we present a new biogeochemical model that represents the food web using variable stoichiometry. It contains the classic compartments such as zooplankton, phytoplankton, and heterotrophic bacteria and a newly added compartment to represent two types of mixotrophic protists: non-constitutive mixotrophs (NCMs) and constitutive mixotrophs (CMs). We demonstrate that the model correctly reproduces the characteristics of NCMs and CMs and proceed to study the impact of light and nutrient limitation on planktonic ecosystem structure in a highly dynamic Mediterranean coastal area, namely the Bay of Marseille (BoM, France), paying special attention to the dynamics of mixotrophic protists in these limiting conditions. In addition, we investigate the carbon, nitrogen, and phosphorus fluxes associated with mixotrophic protists and showed the following: (i) the portion of the ecosystem in terms of the percentage of carbon biomass occupied by NCMs decreases when resources (nutrient and prey concentrations) decrease, although their mixotrophy allows them to maintain a carbon biomass almost as significant as the copepod one (129.8 and 148.7 mmolCm-3 , respectively), as photosynthesis increases as a food source, and (ii) the portion of the ecosystem in terms of the percentage of carbon biomass occupied by CM increases when nutrient concentrations decrease due to their capability to ingest prey to supplement their N and P needs. In addition to providing new insights regarding the conditions that lead to the emergence of mixotrophs in the BoM, this work provides a new tool to perform long-term studies and predictions of mixotroph dynamics in coastal environments under different environmental forcings. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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41. A Spectral Wave Model for Inhomogeneous Water Wave Fields Using the Quasi-Coherent Theory.
- Author
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Baltikas, Vasilis and Krestenitis, Yannis N.
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WATER waves ,OCEAN waves ,STOCHASTIC models ,COHERENCE (Physics) - Abstract
A numerical stochastic wave model was developed in this study based on the quasi-coherent theoretical framework proposed by Smit and Janssen in 2013. Subsequently, the model was implemented to reproduce and cross-confirm the findings of the quasi-coherent (QC) spectral wave modeling approach. The process included simulations of experiments conducted by Vincent and Briggs regarding waves propagating over a submerged shoal. The results of the simulations agree with the expected results of the QC theory, which can account for the spatial coherence of inhomogeneous wave fields and capture wave interference more accurately than conventional spectral wave models. In addition, extra insight was gained about aspects of the overall numerical implementation of the QC theory. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
42. Morphological Modelling to Investigate the Role of External Sediment Sources and Wind and Wave-Induced Flow on Sand Bank Sustainability: An Arklow Bank Case Study.
- Author
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Creane, Shauna, O'Shea, Michael, Coughlan, Mark, and Murphy, Jimmy
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OCEAN zoning ,MARINE sediments ,SAND waves ,SEDIMENTS ,SAND ,SEDIMENT transport - Abstract
Offshore anthropogenic activities such as the installation of Offshore Renewable Energy (ORE) developments and sediment extraction for marine aggregates have been shown to disrupt current flow, wave propagation, and sediment transport pathways, leading to potential environmental instability. Due to the complexity of the interconnected sediment transport pathways in the south-western Irish Sea combined with an increase in planned anthropogenic activities, the assessment of this risk is imperative for the development of a robust marine spatial plan. Subsequently, this study uses two-dimensional morphological modelling to build upon previous studies to assess the dependency of Arklow Bank's local sediment transport regime on external sediment sources. Additionally, scenario modelling is used to identify vulnerable areas of this offshore linear sand bank to wind and wave-forcing and to examine the nature of this impact. A sediment budget is estimated for Arklow Bank, whereby seven source and nine sink pathways are identified. New evidence to support the exchange of sediment between offshore sand banks and offshore independent sand wave fields is also provided. The areas of the bank most vulnerable to changes in external sediment sources and the addition of wind- and wave-induced flow are analogous. These high vulnerability zones (HVZs) align with regions of residual cross-flow under pure current conditions. The restriction of sediment sources off the southern extent of Arklow Bank impacts erosion and accretion patterns in the mid- and northern sections of the bank after just one lunar month of simulation. Where tidal current is the primary driver of sand bank morphodynamics, wind- and wave-induced flow is shown to temporarily alter sediment distribution patterns. Wind and wave-induced flow can both accelerate and decelerate the east-west fluctuation of the upper slopes of the bank, yet the nature of this impact is inconsistent due to the misalignment of the directionality of these two forces. The methods and new knowledge derived from this study are directly applicable to tidally-dominated environments outside the Irish Sea. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
43. Contrasted patterns in climate change risk for Mediterranean fisheries.
- Author
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Pita I, Mouillot D, Moullec F, and Shin YJ
- Subjects
- Animals, Biodiversity, Ecosystem, Fishes, Humans, Mediterranean Sea, Climate Change, Fisheries
- Abstract
Climate change is rapidly becoming one of the biggest threats to marine life, and its impacts have the potential to strongly affect fisheries upon which millions of people rely. This is particularly crucial for the Mediterranean Sea, which is one of the world's biodiversity hotspots, one of the world's most overfished regions, and where temperatures are rising 25% faster than in the rest of the ocean on average. In this study, we calculated a vulnerability index for 100 species that compose 95% of the Mediterranean catches, through a trait-based approach. The Climate Risk Assessment (CRA) methodology was subsequently used to assess the risks due to climate change of Mediterranean fisheries. We found that the northern Mediterranean fisheries target more vulnerable species than their southern counterparts. However, when combining this catch-based vulnerability with a suite of socio-economic parameters, north African countries stand out as the most vulnerable to climate change impacts. Indeed, considering countries' exposure of the fisheries sector and their vulnerability to climate change, a sharp contrast between northern and southern Mediterranean appears, with Egypt and Tunisia scoring the highest risk. By integrating a trait-based approach on targeted marine species with socio-economic features, our analysis helps to better understand the ramifications of climate change consequences on Mediterranean fisheries and highlights the regions that could potentially be particularly affected., (© 2021 John Wiley & Sons Ltd.)
- Published
- 2021
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44. Comparison of the Coastal and Regional Ocean Community Model (CROCO) and NCAR-LES in Non-hydrostatic Simulations.
- Author
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Fan, Xiaoyu, Fox-Kemper, Baylor, Suzuki, Nobuhiro, Li, Qing, Marchesiello, Patrick, Auclair, Francis, Sullivan, Peter P., and Hall, Paul S.
- Subjects
SPEED of sound ,OCEAN ,TURBULENCE ,TRUST ,VISCOSITY ,TSUNAMIS - Abstract
Advances in coastal modeling and computation provide the opportunity for examining non-hydrostatic and compressible fluid effects at very small scales, but the cost of these new capabilities and the accuracy of these models versus trusted non-hydrostatic codes has yet to be determined. Here the Coastal and Regional Ocean COmmunity model (CROCO) and the NCAR Large-Eddy Simulations (NCAR-LES) code base are compared with a focus on their simulation accuracy and computational efficiency. These models differ significantly in numerics and capabilities, so they are run on common classic problems of surface-forced, boundary-layer turbulence. In accuracy, we compare turbulence statistics, including the effect of the explicit sub-grid scale (SGS) parameterization, the effect of the second (dilatational) viscosity and the sensitivity to the speed-of-sound, which is used as part of the CROCO compressible turbulence formulation. To gauge how far CROCO is from the NCAR-LES, we first compare the NCAR-LES with two other LES codes (PALM and Oceanigans). To judge efficiency of CROCO, strong and weak scaling simulation sets vary different problem sizes and workload per processor, respectively. Additionally, the effects of 2D decomposition of CROCO and NCAR-LES and supercomputer settings are tested. In sum, the accuracy comparison between CROCO and the NCAR-LES is similar to the NCAR-LES versus other LES codes. However, the additional capabilities of CROCO (e.g., nesting and realism) and its compressible turbulence formulation come with roughly an order of magnitude of additional costs despite efforts to reduce them by adjusting the second viscosity and sound speed as far as accuracy allows. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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- View/download PDF
45. Kilometer-scale trends and variability of the Adriatic present climate (1987–2017).
- Author
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Tojčić, Iva, Denamiel, Cléa, and Vilibić, Ivica
- Subjects
ATMOSPHERIC models ,HUMIDITY ,WIND speed ,REMOTE sensing ,SEAWATER salinity ,CLIMATE change ,MERIDIONAL overturning circulation - Abstract
We present the Adriatic atmosphere–ocean trends and variability simulated by the kilometer-scale Adriatic Sea and Coast (AdriSC) climate model during the 1987–2017 period. As the AdriSC model has been successfully validated over the entire basin against an extensive dataset of in situ measurements and remote sensing products, the reliability of the presented results at the regional (basin-wide) and local (sub-domains) scales is high. We found that trends and variability in the atmosphere reveal strong land-sea contrasts with (1) stronger temperature trends associated with lower, mostly seasonal, variability over the Adriatic Sea than over the land and (2) positive trends of wind speed and negative trends of relative humidity associated with high, mostly seasonal, variability over the sea and vice versa over the land. While, in the ocean, the analysis highlights several processes: (1) extensive warming by the atmosphere at the surface during summer, affecting both temperature and salinity, (2) shallowing of the advection of the saline Levantine Intermediate Water inflow into the Adriatic, (3) decrease of the Adriatic deep water outflow and therefore the Adriatic-Ionian thermohaline circulation, (4) warming of near-bottom waters, in particular in the middle and northern Adriatic, and (5) shrinking and weakening of the Southern Adriatic Gyre, in particular at its center. We thus demonstrate that kilometer-scale coupled atmosphere–ocean modelling is an indispensable tool for proper quantification of climate change in complex coastal basins, as it captures local characteristics not properly reproduced by present state-of-the-art regional climate models with an order of magnitude coarser resolutions. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
46. A numerical approach to model sound generation by ocean dynamical processes: The case of surface gravity waves.
- Author
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Dumont, Pierre-Antoine, Auclair, Francis, Stéphan, Yann, and Dumas, Franck
- Subjects
GRAVITY waves ,ULTRASONIC waves ,OCEAN ,ACOUSTIC emission testing - Abstract
The new generation of regional ocean models can provide the evolution of both the slow and fast components of pressure, consequently opening original opportunities to evaluate the acoustic signal generated by ocean slower dynamical processes. This capacity is evaluated in the case of surface waves, with a focus on the hydro-acoustic precursors and on the acoustic modes induced by supersonic surface wave groups. The consistency with theory confirms that such models are adapted to answer recent interrogations by Wunsch [(2022). J. Acoust. Soc. Am. 152(4), 2160–2168] about evaluating the noise of ocean processes. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
47. Coarse‐grained, marine, sub‐wave base, high‐angle clinoform sets: A little‐known outcrop facies illustrated by Jurassic examples from East Greenland.
- Author
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Surlyk, Finn and Larsen, Michael
- Subjects
SLOPES (Physical geography) ,FACIES ,WATER depth ,CRATONS ,RIFTS (Geology) ,BED load ,SAND waves - Abstract
Outcrops of coarse‐grained, high‐angle clinoform sets are mainly thought to represent Gilbert‐type deltas. Superficially similar clinoform sets may, however, form in marine, sub‐wave base settings. They are interpreted to have formed as a result of storms where downwelling, seaward‐directed currents transported sand from the coastal area and shoreface across the shelf in suspension or as bedload to be deposited as clinothems. An additional transport of sand took place by strong coast‐parallel currents. The clinoform sets appear to be associated with rift events, the creation of accommodation space and an increasing supply of coarse‐grained sediment. A major protracted rift phase was initiated in East Greenland in Middle Jurassic times and intensified through the Late Jurassic to reach a climax close to the Jurassic–Cretaceous boundary. Rifting caused uplift of borderlands, creation of accommodation space and development of shallow marine shelves passing offshore into submarine slopes and deeper basinal areas. Each rift event was accompanied by the formation of clinoform sets prograding seawards towards the east and southeast away from the cratonic coastline in water depths below the wave base. The clinoform sets are interpreted as typical motifs for rift events in the relatively shallow epeiric Jurassic seaway between East Greenland and Norway. Outcrops of such sets represent a little‐known, commonly misinterpreted sedimentary system and may serve as motifs for rifting in shallow marine areas elsewhere in the geological record. Similar sets have been recorded in outcrop from the Mediterranean, and elsewhere and are probably more common than hitherto realized. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
48. Seasonal and interannual variability of the pelagic ecosystem and of the organic carbon budget in the Rhodes Gyre (eastern Mediterranean): influence of winter mixing.
- Author
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Habib, Joelle, Ulses, Caroline, Estournel, Claude, Fakhri, Milad, Marsaleix, Patrick, Pujo-Pay, Mireille, Fourrier, Marine, Coppola, Laurent, Mignot, Alexandre, Mortier, Laurent, and Conan, Pascal
- Subjects
HEAT convection ,SEASONS ,HEAT losses ,MIXING height (Atmospheric chemistry) ,CARBON ,GEOTHERMAL ecology - Abstract
The Rhodes Gyre is a cyclonic persistent feature of the general circulation of the Levantine Basin in the eastern Mediterranean Sea. Although it is located in the most oligotrophic basin of the Mediterranean Sea, it is a relatively high primary production area due to strong winter nutrient supply associated with the formation of Levantine Intermediate Water. In this study, a 3D coupled hydrodynamic–biogeochemical model (SYMPHONIE/Eco3M-S) was used to characterize the seasonal and interannual variability of the Rhodes Gyre's ecosystem and to estimate an annual organic carbon budget over the 2013–2020 period. Comparisons of model outputs with satellite data and compiled in situ data from cruises and Biogeochemical-Argo floats revealed the ability of the model to reconstruct the main seasonal and spatial biogeochemical dynamics of the Levantine Basin. The model results indicated that during the winter mixing period, phytoplankton first progressively grow sustained by nutrient supply. Then, short episodes of convection driven by heat loss and wind events, favoring nutrient injections, organic carbon export, and inducing light limitation on primary production, alternate with short episodes of phytoplankton growth. The estimate of the annual organic carbon budget indicated that the Rhodes Gyre is an autotrophic area, with a positive net community production in the upper layer (0–150 m) amounting to 31.2 ± 6.9 gCm-2yr-1. Net community production in the upper layer is almost balanced over the 7-year period by physical transfers, (1) via downward export (16.8 ± 6.2 gCm-2yr-1) and (2) through lateral transport towards the surrounding regions (14.1 ± 2.1 gCm-2yr-1). The intermediate layer (150–400 m) also appears to be a source of organic carbon for the surrounding Levantine Sea (7.5 ± 2.8 gCm-2yr-1) mostly through the subduction of Levantine Intermediate Water following winter mixing. The Rhodes Gyre shows high interannual variability with enhanced primary production, net community production, and exports during years marked by intense heat losses and deep mixed layers. However, annual primary production appears to be only partially driven by winter vertical mixing. Based on our results, we can speculate that future increase of temperature and stratification could strongly impact the carbon fluxes in this region. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
49. Influence of shark tourism on the activity and physiological condition of a non-focal pelagic fish.
- Author
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Clarke, Thomas M, Whitmarsh, Sasha K, Champion, Curtis, Pederson, Hugh, Meyer, Lauren, Dennis, Joshua D, Dwyer, Ross G, and Huveneers, Charlie
- Subjects
ECOTOURISM ,YELLOWTAIL ,PELAGIC fishes ,ANIMAL mechanics ,ARCHIPELAGOES ,BIOELECTRIC impedance - Abstract
Wildlife tourism can have adverse effects on the behaviours and movements of animals, with implications for the health and fitness of individuals and populations. We used acoustic-tracking to show that food-based attractants used in shark-tourism increases activity (15%) and burst behaviours (60%) in yellowtail kingfish (Seriola lalandi, n = 18). Increased activity was restricted to periods when kingfish were on the same side of the island group as berleying tourism vessels, but decreased after operators left the site. Despite the raised activity and frequency of burst swimming events, the physiological condition of kingfish (n = 39, 6 tagged, and 33 untagged) measured using bioelectrical impedance analysis remained consistent with kingfish from control sites not exposed to tourism. This suggests that kingfish were able to compensate raised energy expenditure by feeding on bait and berley used by operators or through natural foraging. We highlight that the effects of provisioning from wildlife tourism can extend beyond changes in behaviours and movements and can additionally influence the energetic condition of non-focal animals through increased activity. However, supplemental food-sources provided through wildlife tourism may be sufficient to compensate for the increased energy expenditure and lessen the effects of tourism on individual fitness and health. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
50. Study on calculation model and risk area of radionuclide diffusion in coastal waters under nuclear leakage accidents with different levels.
- Author
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Li, Zichao, Chen, Rongchang, Zhou, Tao, Liu, Chen, Si, Guangcheng, and Xue, Qingqing
- Published
- 2023
- Full Text
- View/download PDF
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