A5057976978- Oceanographic and Atmospheric Processes
- Climate variability and models
- Ocean Waves and Remote Sensing
- Tropical and Extratropical Cyclones Research
- Meteorological Phenomena and Simulations
- Geology and Paleoclimatology Research
- Geological formations and processes
- Marine and coastal ecosystems
- Hydrocarbon exploration and reservoir analysis
- Fluid Dynamics and Turbulent Flows
- Aquatic and Environmental Studies
- Geophysics and Gravity Measurements
- Solar and Space Plasma Dynamics
- Marine and environmental studies
- Methane Hydrates and Related Phenomena
- Plant Pathogens and Resistance
- Genetic and Environmental Crop Studies
- Geological Studies and Exploration
- Aeolian processes and effects
- Geological and Geophysical Studies
- Technology Assessment and Management
- Coastal and Marine Dynamics
- Soil Moisture and Remote Sensing
- Space Science and Extraterrestrial Life
- Opportunistic and Delay-Tolerant Networks
Institut de Recherche pour le Développement
2015-2024
Université de Bretagne Occidentale
2015-2024
Ifremer
2015-2024
Centre National de la Recherche Scientifique
2015-2024
Institut Universitaire Européen de la Mer
2016-2024
Laboratory for Ocean Physics and Satellite Remote Sensing
2016-2024
Laboratoire d’Études en Géophysique et Océanographie Spatiales
2017-2024
University of Oxford
2017
Institut Océanographique
2010-2013
Planetary Science Institute
2011
In order to clarify the link between ocean salt content (OSC) conservation and freshwater flux formulation in general circulation models (OGCMs), a varying level thickness, nonlinear free surface version of OPA is presented. Linear/nonlinear equations are solved using an original approach based on explicit damping fast external gravity waves. The method leaves both potential vorticity equation equilibrium state unchanged. Its numerics cost quite similar those implicit schemes. When...
A surface Quasi‐Geostrophy based (eSQG) method to diagnose the vertical velocity field from Sea Surface Height (SSH) is assessed using high resolution simulations. These simulations concern a turbulent eddy with large Rossby numbers and energetic wind‐driven motions. Results indicate that low‐frequency velocities (and also horizontal motions) can be reconstructed within range of scales between 20 km 400 down 500 m. The only information needed single high‐resolution SSH snapshot on...
Abstract The Persian Gulf feeds a warm and salty outflow in the of Oman (northern Arabian Sea). salt climatological distribution is relatively smooth Oman, signature slope current carrying waters difficult to distinguish hundreds kilometers past Strait Hormuz, contrast other outflows world ocean. This study focuses on mechanisms involved spreading Water (PGW) using regional primitive equation numerical simulation. authors show that dispersion PGW occurs through regime distinct from, for...
Abstract The Great Whirl (GW) is a persistent anticyclonic mesoscale eddy that observed seasonally in the Arabian Sea during period embedding 3 months of southwest monsoon (June–July–August) at quasi‐steady location. Its dynamics remain unclear despite it being one largest coherent vortices world ocean. Realistic regional numerical experiments using ROMS are performed to investigate life cycle GW, which not well resolved by sparse available situ measurements region. Using set sensitivity and...
Abstract This study focuses on the description of an oceanic variant Charney baroclinic instability, arising from joint presence (i) equatorward buoyancy gradient that extends surface into ocean interior and (ii) reduced subsurface stratification, for example, as produced by wintertime convection or subduction. analyzes forced dissipative simulations with without instability (C-BCI). In former, C-BCI strengthens near-surface frontal activity important consequences in terms turbulent...
Aphanomyces root rot, caused by euteiches, is one of the most-important diseases pea (Pisum sativum L.) worldwide. The development resistant varieties a major objective to manage disease. Consistent quantitative trait loci (QTL) controlling partial resistance were discovered from linkage mapping and genome-wide association studies. This study aimed validate QTL effects identify effective combinations under contaminated field conditions, exploiting Near-Isogenic Lines (NILs) carrying alleles...
Abstract High-resolution simulations of β-channel, zonal-jet, baroclinic turbulence with a three-dimensional quasigeostrophic (QG) model including surface potential vorticity (PV) are analyzed emphasis on the competing role interior and PV (associated isopycnal outcropping). Two distinct regimes considered: Phillips case, where gradient changes sign twice in interior, Charney at surface. The case is typical simplified test beds that have been widely used to investigate effect ocean eddies...
Abstract By combining all Argo profiles for the period 2002 to present, a cumulative density function is constructed on 3‐D grid of global ocean. This quantifies statistics isopycnals: time‐averaged density, root‐mean square isopycnal displacement, and eddy available potential energy (EAPE). EAPE analogue kinetic energy, but reservoir. Because it essentially tied spatial structure magnitude mesoscale activity, an important quantity that should be useful evaluate resolving/permitting model...
Abstract. With the increase in computational power, ocean models with kilometer-scale resolution have emerged over last decade. These been used for quantifying energetic exchanges between spatial scales, informing design of eddy parametrizations, and preparing observing networks. The resolution, however, has drastically increased size model outputs, making it difficult to transfer analyze data. It remains, nonetheless, primary importance assess more systematically realism these models. Here,...
We address the problem of cyclone-anticyclone asymmetry in geophysical turbulence using a direct numerical simulation with high Reynolds number $\mathrm{Re}\ensuremath{\sim}15\text{ }000$ that includes an active upper boundary and interior dynamics. The regime, characterized by finite Rossby ($\mathrm{Ro}\ensuremath{\sim}0.6$) strongly departs from classical quasigeostrophic regime. resolution is pushed to limit today's supercomputer capabilities ensuring more than two decades free viscous...
Abstract The upper ocean is energetic at scales below the Rossby deformation radius owing to existence of internal waves and submesoscale fronts vortices. These contribute significantly energy dissipation, tracer mixing, exchanges between surface layer, interior, atmospheric boundary layer. Internal motions both undergo strong spatial seasonal variations, driven by different mechanisms. Here, we investigate sea signature its seasonality using linear wave theory a high‐resolution realistic...
Over mid-ocean ridges, the interaction between currents and topography gives rise to complex flows, which drive transport properties of biogeochemical constituents, especially those associated with hydrothermal vents, thus impacting ecosystems. This paper describes circulation in rift valley along Azores sector North Mid-Atlantic Ridge, using a combination \textit{in-situ} data from several surveys realistic high-resolution modelling. It confirms presence mean deep current an up-valley...
High resolution simulations of ocean turbulence with Rossby number order one have revealed that upper layer dynamics significantly differs from the interior dynamics. As reported before, is characterized shallow velocity spectrum corresponding to kinetic energy distributed over a spectral range mesoscales small scales. This driven by small-scale frontogenesis related surface density anomalies. Interior steeper and potential vorticity anomalies set up baroclinic instability. Impact divergent...
Abstract Using numerical simulations forced by a uniform realistic wind time series, the authors show that presence of mesoscale eddy field at midlatitudes accelerates vertical propagation wind-forced near-inertial waves (NIW) and produces emergence maximum velocity into deep ocean (around 2500 m) characterized mean amplitude 25 m day−1, dominant 2f frequency, scales as small O(30 km). These results differ from previous studies reported smaller depth larger scales. The observed in present...
Despite its climatic and ecosystemic significance, the coastal upwelling that takes place off Oman is not well understood. A primitive-equation, regional model forced by climatological wind stress used to investigate dynamics compare it with better-known Eastern Boundary Upwellings (EBUs). The solution compares favorably existing observations, simulating seasonal cycles of thermal structure, surface circulation (mean turbulent), sea-surface temperature (SST). There a 1.5-month lag between...
Abstract Internal tides are a predominant source of high‐frequency variability and diapycnal mixing in the ocean. Understanding their dynamics lifecycle is necessary to better understand role ocean circulation. In this study, we describe quantify internal tide generation, propagation, dissipation sector North Mid‐Atlantic Ridge, using high‐resolution numerical simulations with realistic bathymetry stratification. We show that generation tides, as well distribution among vertical modes,...
Abstract. This paper presents MQGeometry, a multi-layer quasi-geostrophic (QG) equation solver for non-rectangular geometries. We advect the potential vorticity (PV) with finite volumes to ensure global PV conservation using staggered discretization of and stream function (SF). Thanks this staggering, is defined inside domain, removing need define on domain boundary. compute fluxes upwind-biased interpolations whose implicit dissipation replaces usual explicit (hyper-)viscous dissipation....
Review of three studies devoted to the available potential energy (APE) leads proposal a diagnosis for APE, well-suited rotating stratified flows within primitive equations (PE) framework in which anharmonic effects (due large vertical displacements isopycnals) are permitted. The chosen is based on APE definition Holliday & McIntyre ( J. Fluid Mech. , vol. 107, 1981, pp. 221–225) and uses background stratification Winters et al . 289, 1995, 115–128). Subsequent evaluation PE direct...
Abstract. The aim of this study is to clarify the role Southern Ocean storms on interior mixing and meridional overturning circulation. A periodic idealized numerical model has been designed represent key physical processes a zonal portion located between 70 40° S. It incorporates ingredients deemed essential for functioning: rough topography, seasonally varying air–sea fluxes, high-latitude with analytical form. forcing strategy ensures that time mean wind stress same different simulations,...
Abstract Carbon budgets of hydrothermal plumes result from the balance between carbon sinks through plume chemoautotrophic processes and release via microbial respiration. However, lack comprehensive analysis metabolic biomass production rates hinders an accurate estimate their contribution to deep ocean cycle. Here, we use a biogeochemical model autotrophic heterotrophic communities in validate it with situ data. We show how substrate limitation might prevent net chemolithoautotrophic...
With a new unifying model for layered rotating shallow-water (RSW) and quasi-geostrophic (QG) equations, this paper sheds light on the relation between these two sets of equations. We propose here formulation equations as projection This QG uses same prognostic variables RSW, namely velocity layer thickness, restoring proximity It allows direct access to ageostrophic velocities hidden in geostrophic resolved by opens path studying difference RSW using underlying numerical discretization....
Abstract. This study investigates the linear and non-linear instability of a buoyant coastal current flowing along sloping topography. In fact, bathymetry strongly impacts formation meanders or eddies leads to different dynamical regimes that can both enhance prevent cross-shore transport. We use Regional Ocean Modeling System (ROMS) run simulations in an idealized channel configuration, using fixed structure testing its unstable evolution for various depths topographic slopes. The...