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A numerical model for ocean ultra-low frequency noise: Wave-generated acoustic-gravity and Rayleigh modes ArchiMer
Ardhuin, Fabrice; Lavanant, Thibaut; Obrebski, Mathias; Marie, Louis; Royer, Jean-yves; D'Eu, Jean-francois; Howe, Bruce M.; Lukas, Roger; Aucan, Jerome.
The generation of ultra-low frequency acoustic noise (0.1 to 1 Hz) by the nonlinear interaction of ocean surface gravity waves is well established. More controversial are the quantitative theories that attempt to predict the recorded noise levels and their variability. Here a single theoretical framework is used to predict the noise level associated with propagating pseudo-Rayleigh modes and evanescent acoustic-gravity modes. The latter are dominant only within 200 m from the sea surface, in shallow or deep water. At depths larger than 500 m, the comparison of a numerical noise model with hydrophone records from two open-ocean sites near Hawaii and the Kerguelen islands reveal: (a) Deep ocean acoustic noise at frequencies 0.1 to 1 Hz is consistent with the...
Tipo: Text
Ano: 2013 URL: http://archimer.ifremer.fr/doc/00176/28748/27211.pdf
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Detection of microseismic compressional (P) body waves aided by numerical modeling of oceanic noise sources ArchiMer
Obrebski, Mathias; Ardhuin, Fabrice; Stutzmann, Eleonore; Schimmel, Martin.
Among the different types of waves embedded in seismic noise, body waves present appealing properties but are still challenging to extract. Here we first validate recent improvements in numerical modeling of microseismic compressional (P) body waves and then show how this tool allows fast detection and location of their sources. We compute sources at similar to 0.2 Hz within typical P teleseismic distances (30-90 degrees) from the Southern California Seismic Network and analyze the most significant discrete sources. The locations and relative strengths of the computed sources are validated by the good agreement with beam-forming analysis. These 54 noise sources exhibit a highly heterogeneous distribution, and cluster along the usual storm tracks in the...
Tipo: Text Palavras-chave: Compressionnal body waves; Noise source; Double frequency microseism; Numerical modeling.
Ano: 2013 URL: http://archimer.ifremer.fr/doc/00161/27251/25448.pdf
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Wave Attenuation Through an Arctic Marginal Ice Zone on 12 October, 2015: 1. Measurement of Wave Spectra and Ice Features From Sentinel-1A ArchiMer
Stopa, J. E.; Ardhuin, Fabrice; Thomson, Jim; Smith, Madison M.; Kohout, Alison; Doble, Martin; Wadhams, Peter.
A storm with significant wave heights exceeding 4 m occurred in the Beaufort Sea on 11 to 13 October, 2015. The waves and ice were captured on 12 October by the Synthetic Aperture Radar (SAR) on board Sentinel‐1A, with Interferometric Wide swath images covering 400 × 1100 km at 10 m resolution. This dataset allows the estimation of wave spectra across the marginal ice zone (MIZ) every 5 km, over 400 km of sea ice. Since ice attenuates waves with wavelengths shorter than 50 m in a few kilometers, the longer waves are clearly imaged by SAR in sea ice. Obtaining wave spectra from the image requires a careful estimation of the blurring effect produced by unresolved wavelengths in the azimuthal direction. Using in‐situ wave buoy measurements as reference, we...
Tipo: Text Palavras-chave: Wave-ice interaction; Arctic Ocean marginal ice zone; Sentinel-1A SAR; Arctic Sea State Boundary Layer Physics Program; Remote sensing; Wave attenuation.
Ano: 2018 URL: https://archimer.ifremer.fr/doc/00439/55084/56519.pdf
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A unified deep-to-shallow water wave-breaking probability parameterization ArchiMer
Filipot, Jean-francois; Ardhuin, Fabrice; Babanin, Alexander V..
Breaking probabilities and breaking wave height distributions (BWHDs) in deep, intermediate, and shallow water depth are compared, and a generic parameterization is proposed to represent the observed variability of breaking parameters as a function of the nondimensional water depth. In intermediate and deep water, where waves of different scales may have markedly different breaking probabilities, a BWHD as a function of wave frequency is proposed and validated with intermediate-depth and deep water observational data. The current study focuses on waves with frequencies between 0.55 and 3.45 times the peak frequency f(p). For the dominant frequency, the integration of the frequency-dependent BWHD provides a breaking probability that reproduces the known...
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Ano: 2010 URL: http://archimer.ifremer.fr/doc/00030/14098/11330.pdf
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How moderate sea states can generate loud seismic noise in the deep ocean ArchiMer
Obrebski, Mathias; Ardhuin, Fabrice; Stutzmann, E.; Schimmel, M..
The location of oceanic sources of the micrometric ground displacement recorded at land stations in the 0.1-0.3 Hz frequency band ("double frequency microseisms") is still poorly known. Here we use one particularly strong noise event in the Pacific to show that small swells from two distant storms can be a strong deep-water source of seismic noise, dominating temporarily the signals recorded at coastal seismic stations. Our interpretation is based on the analysis of noise polarization recorded all around the source, and the good fit achieved for this event and year-round between observed and modeled seismic data. The model further suggests that this is a typical source of these infrequent loud noise bursts, which supports previous inconclusive evidences of...
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Ano: 2012 URL: http://archimer.ifremer.fr/doc/00085/19625/17262.pdf
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Turbulence Modeling and Wave-Current Interactions ArchiMer
Bennis, Anne-claire; Dumas, Franck; Ardhuin, Fabrice; Blanke, Bruno.
The mechanics of rip currents are complex, involving interactions between waves, currents, water levels and the bathymetry, that present particular challenges for numerical models. Here, the effects of a grid-spacing dependent horizontal mixing on the wave-current interactions are studied. Near the shore, wave rays diverge from channels towards bar crests because of refraction by topography and currents, in a way that depends on the rip current intensity which is itself modulated by the horizontal mixing. At low resolution with the grid-spacing dependent horizontal mixing, the wave motion is the same for both coupling modes because the wave deviation by the currents is weak. In high resolution case, however, classical results are found with the stabilizing...
Tipo: Text Palavras-chave: Numerical modeling; Rip currents; Turbulence modeling; Wave-current interactions.
Ano: 2015 URL: https://archimer.ifremer.fr/doc/00601/71288/69695.pdf
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Observation of swell dissipation across oceans ArchiMer
Ardhuin, Fabrice; Chapron, Bertrand; Collard, Fabrice.
Global observations of ocean swell, from satellite Synthetic Aperture Radar data, are used to estimate the dissipation of swell energy for a number of storms. Swells can be very persistent with energy e-folding scales exceeding 20,000 km. For increasing swell steepness this scale shrinks systematically, down to 2800 km for the steepest observed swells, revealing a significant loss of swell energy. This value corresponds to a normalized energy decay in time beta = 4.2 x 10(-6) s(-1). Many processes may be responsible for this dissipation. The increase of dissipation rate in dissipation with swell steepness is interpreted as a laminar to turbulent transition of the boundary layer, with a threshold Reynolds number of the order of 100,000. These observations...
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Ano: 2009 URL: http://archimer.ifremer.fr/doc/2009/publication-6452.pdf
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Surface Roughness Imaging of Currents Shows Divergence and Strain in the Wind Direction ArchiMer
Rascle, Nicolas; Chapron, Bertrand; Ponte, Aurelien; Ardhuin, Fabrice; Klein, Patrice.
Images of sea surface roughness-for example, obtained by synthetic aperture radars (SAR) or by radiometers viewing areas in and around the sun glitter-at times provide clear observations of meso- and sub-mesoscale oceanic features. Interacting with the surface wind waves, particular deformation properties of surface currents are responsible for those manifestations. Ignoring other sources of surface roughness variations, the authors limit their discussion to the mean square slope (mss) variability. This study confirms that vortical currents and currents with shear in the wind direction shall not be expressed in surface roughness images. Only divergent currents or currents with no divergence but strained in the wind direction can exhibit surface roughness...
Tipo: Text Palavras-chave: Circulation/ Dynamics; Ageostrophic circulations; Atmosphere-ocean interaction; Mesoscale processes; Wind waves; Atm/Ocean Structure/ Phenomena; Boundary layer; Sea state.
Ano: 2014 URL: https://archimer.ifremer.fr/doc/00210/32170/30619.pdf
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Corrigenda of ’Explicit wave-averaged primitive equations using a Generalized Lagrangian Mean’ ArchiMer
Ardhuin, Fabrice; Rascle, Nicolas; Belibassakis, K. A..
Ardhuin et al. (2008) gave a second-order approximation in the wave slope of the exact Generalized Lagrangian Mean (GLM) equations derived by Andrews and McIntyre (1978), and also performed a coordinate transformation, going from a from GLM to a ’GLMz’ set of equations. That latter step removed the wandering of the GLM mean sea level away from the Eulerian-mean sea level, making the GLMz flow non-divergent. That step contained some inaccuarate statements about the coordinate transformation, while the rest of the paper contained an error on the surface dynamic boundary condition for viscous stresses. I am thankful to Mathias Delpey and Hidenori Aiki for pointing out these errors, which are corrected below.
Tipo: Text Palavras-chave: Wave-current; GLM; Air-sea.
Ano: 2017 URL: http://archimer.ifremer.fr/doc/00380/49165/49601.pdf
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The SARAL/AltiKa mission: A step forward to the future of altimetry ArchiMer
Verron, Jacques; Bonnefond, Pascal; Andersen, Ole; Ardhuin, Fabrice; Bergé-nguyen, Muriel; Bhowmick, Suchandra; Blumstein, Denis; Boy, François; Brodeau, Laurent; Crétaux, Jean-françois; Dabat, Mei Ling; Dibarboure, Gérald; Fleury, Sara; Garnier, Florent; Gourdeau, Lionel; Marks, Karen; Queruel, Nadège; Sandwell, David; Smith, Walter H.f.; Zaron, Ed.
The CNES/ISRO altimetric satellite SARAL/AltiKa was launched in February 2013 and since then has provided useful data for various scientific and operational applications in oceanography, hydrology, cryospheric sciences and geodesy. However, a Reaction Wheel problem forced relaxation of the repeatability constraint on the satellite’s orbit, which has been drifting slowly since July 2016. Beyond the expected contributions of this mission and its very good integration into the objectives of the constellation of altimetric satellites, it has become more and more apparent that specific contributions and innovations related to the main specification of SARAL/AltiKa, that is to say the use of the Ka-band, have clearly emerged. The advantages of the Ka-band are in...
Tipo: Text Palavras-chave: Satellite; Altimetry; Ka-band.
Ano: 2020 URL: https://archimer.ifremer.fr/doc/00607/71878/70573.pdf
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A global wave parameter database for geophysical applications. Part 2: Model validation with improved source term parameterization ArchiMer
Rascle, Nicolas; Ardhuin, Fabrice.
A multi-scale global hindcast of ocean waves is presented that covers the years 1994-2012, based on recently published parameterizations for wind sea and swell dissipation [Ardhuin, F., Rogers, E., Babanin, A., Filipot, J.-F., Magne, R., Roland, A., van der Westhuysen, A., Queffeulou, P., Lefevre, J.-M., Aouf, L., Collard, F., 2010. Semi-empirical dissipation source functions for wind-wave models: Part I. Definition, calibration and validation. J. Phys. Oceanogr. 40 (9), 1917-1941]. Results from this hindcast include traditional wave parameters, like the significant wave height and mean periods, and we particularly consider the accuracy of the results for phenomenal sea states, with significant heights above 14 m. Using unbiased winds, there is no evidence...
Tipo: Text Palavras-chave: Waves; Hindcast; Air-sea fluxes; Stokes drift; Mean square slope; Seismic noise.
Ano: 2013 URL: http://archimer.ifremer.fr/doc/00155/26582/25477.pdf
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Atmospheric storm surge modeling methodology along the French (Atlantic and English Channel) coast ArchiMer
Muller, Heloise; Pineau-guillou, Lucia; Idier, Deborah; Ardhuin, Fabrice.
Storm surge modeling and forecast are the key issues for coastal risk early warning systems. As a general objective, this study aims at improving high-frequency storm surge variations modeling within the PREVIMER system (www.previmer.org), along the French Atlantic and English Channel coasts. The paper focuses on (1) sea surface drag parameterization and (2) uncertainties induced by the meteorological data quality. The modeling is based on the shallow-water version of the model for applications at regional scale (MARS), with a 2-km spatial resolution. The model computes together tide and surge, allowing properly taking into account tide-surge interactions. To select the most appropriate parameterization for the study area, a sensitivity analysis on sea...
Tipo: Text Palavras-chave: Storm surge; MARS; Sea surface drag; Meteorological forcing.
Ano: 2014 URL: http://archimer.ifremer.fr/doc/00219/32982/31404.pdf
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On the coupling of wave and three-dimensional circulation models: Choice of theoretical framework, practical implementation and adiabatic tests ArchiMer
Bennis, Anne-claire; Ardhuin, Fabrice; Dumas, Franck.
Many theoretical approaches and implementations have been proposed for the coupling of the three-dimensional ocean circulation with waves. The theoretical models are reviewed and it is shown that the formulation in terms of the quasi-Eulerian velocity circumvents the essential difficulty of alternative formulations for the Lagrangian mean velocity. Namely, models based on this Lagrangian velocity require an estimation of wave-induced motions to first order in the horizontal gradients of the wave field in order to estimate the vertical flux of wave pseudo-momentum. So far, only three-dimensional wave models have been able to provide these estimates, and all published theories based on the simpler Airy theory are not consistent at the leading order, because...
Tipo: Text Palavras-chave: Wave-current coupling; Radiation stresses; MARS3D; WAVEWATCH III.
Ano: 2011 URL: http://archimer.ifremer.fr/doc/00056/16705/14198.pdf
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Towards Comprehensive Observing and Modeling Systems for Monitoring and Predicting Regional to Coastal Sea Level ArchiMer
Ponte, Rui M.; Carson, Mark; Cirano, Mauro; Domingues, Catia M.; Jevrejeva, Svetlana; Marcos, Marta; Mitchum, Gary; Van De Wal, R. S. W.; Woodworth, Philip L.; Ablain, Michaël; Ardhuin, Fabrice; Ballu, Valérie; Becker, Mélanie; Benveniste, Jérôme; Birol, Florence; Bradshaw, Elizabeth; Cazenave, Anny; De Mey-frémaux, P.; Durand, Fabien; Ezer, Tal; Fu, Lee-lueng; Fukumori, Ichiro; Gordon, Kathy; Gravelle, Médéric; Griffies, Stephen M.; Han, Weiqing; Hibbert, Angela; Hughes, Chris W.; Idier, Déborah; Kourafalou, Villy H.; Little, Christopher M.; Matthews, Andrew; Melet, Angélique; Merrifield, Mark; Meyssignac, Benoit; Minobe, Shoshiro; Penduff, Thierry; Picot, Nicolas; Piecuch, Christopher; Ray, Richard D.; Rickards, Lesley; Santamaría-gómez, Alvaro; Stammer, Detlef; Staneva, Joanna; Testut, Laurent; Thompson, Keith; Thompson, Philip; Vignudelli, Stefano; Williams, Joanne; Williams, Simon D. P.; Wöppelmann, Guy; Zanna, Laure; Zhang, Xuebin.
A major challenge for managing impacts and implementing effective mitigation measures and adaptation strategies for coastal zones affected by future sea level (SL) rise is our limited capacity to predict SL change at the coast on relevant spatial and temporal scales. Predicting coastal SL requires the ability to monitor and simulate a multitude of physical processes affecting SL, from local effects of wind waves and river runoff to remote influences of the large-scale ocean circulation on the coast. Here we assess our current understanding of the causes of coastal SL variability on monthly to multi-decadal timescales, including geodetic, oceanographic and atmospheric aspects of the problem, and review available observing systems informing on coastal SL. We...
Tipo: Text Palavras-chave: Coastal sea level; Sea-level trends; Coastal ocean modeling; Coastal impacts; Coastal adaptation; Observational gaps; Integrated observing system.
Ano: 2019 URL: https://archimer.ifremer.fr/doc/00508/61958/66049.pdf
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SKIM, a Candidate Satellite Mission Exploring Global Ocean Currents and Waves ArchiMer
Ardhuin, Fabrice; Brandt, Peter; Gaultier, Lucile; Donlon, Craig; Battaglia, Alessandro; Boy, François; Casal, Tania; Chapron, Bertrand; Collard, Fabrice; Cravatte, Sophie; Delouis, Jean Marc; De Witte, Erik; Dibarboure, Gerald; Engen, Geir; Johnsen, Harald; Lique, Camille; Lopez-dekker, Paco; Maes, Christophe; Martin, Adrien; Marié, Louis; Menemenlis, Dimitris; Nouguier, Frederic; Peureux, Charles; Rampal, Pierre; Ressler, Gerhard; Rio, Marie-helene; Rommen, Bjorn; Shutler, Jamie D.; Suess, Martin; Tsamados, Michel; Ubelmann, Clement; Van Sebille, Erik; Van Den Oever, Martin; Stammer, Detlef.
The Sea surface KInematics Multiscale monitoring (SKIM) satellite mission is designed to explore ocean surface current and waves. This includes tropical currents, notably the poorly known patterns of divergence and their impact on the ocean heat budget, and monitoring of the emerging Arctic up to 82.5°N. SKIM will also make unprecedented direct measurements of strong currents, from boundary currents to the Antarctic circumpolar current, and their interaction with ocean waves with expected impacts on air-sea fluxes and extreme waves. For the first time, SKIM will directly measure the ocean surface current vector from space. The main instrument on SKIM is a Ka-band conically scanning, multi-beam Doppler radar altimeter/wave scatterometer that includes a...
Tipo: Text Palavras-chave: Ocean current; Tropics; Arctic; Doppler; Altimetry; Sea state; Remote sensing; Ocean waves.
Ano: 2019 URL: https://archimer.ifremer.fr/doc/00498/60964/64372.pdf
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Phenomenal sea states and swell from a North Atlantic Storm in February 2011: a comprehensive analysis ArchiMer
Hanafin, Jennifer; Quilfen, Yves; Ardhuin, Fabrice; Sienkiewicz, Joseph; Queffeulou, Pierre; Obrebski, Mathias; Chapron, Bertrand; Reul, Nicolas; Collard, Fabrice; Corman, David; De Azevedo, Eduardo B.; Vandemark, Doug; Stutzmann, Eleonore.
Tipo: Text
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00094/20538/18197.pdf
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On the Extraction of Microseismic Ground Motion from Analog Seismograms for the Validation of Ocean-Climate Models ArchiMer
Lecocq, Thomas; Ardhuin, Fabrice; Collin, Fabienne; Camelbeeck, Thierry.
We report on a pilot demonstration of the usefulness of analog seismograms to improve the database of ocean storms before the 1980s by providing additional data for the quantitative validation of ocean wave modeling, in particular for extreme events. We present a method for automatic digitization of paper seismograms to extract microseismic ground‐motion periods and amplitudes. Each minute of the original paper records is scanned and vectorized. The amplitudes are calibrated based on the original metadata taken from official bulletins. The digitized time series is processed to extract power spectral densities, which are compared with modeled microseisms levels computed using a numerical ocean wave model. As a case study, we focus on one month of data...
Tipo: Text
Ano: 2020 URL: https://archimer.ifremer.fr/doc/00620/73196/72555.pdf
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Polarized Earth's ambient microseismic noise ArchiMer
Schimmel, M.; Stutzmann, E.; Ardhuin, Fabrice; Gallart, J..
We quantify, analyze, and characterize the frequency-dependent microseismic noise recorded by worldwide distributed seismic stations. Microseismic noise is generated through the interaction of ocean waves. It is the strongest ambient noise, and it is observed everywhere on Earth. We introduce a new approach which permits us to detect polarized signals in the time-frequency domain and which we use to characterize the microseismic noise. We analyze 7 years of continuous seismograms from the global GEOSCOPE network. Microseisms are dominated by Rayleigh waves, and we therefore focus on elliptically polarized signals. The polarized signals are detected in the time-frequency domain through a degree of polarization measure. We design polarization spectra and...
Tipo: Text Palavras-chave: Microseismic noise; Polarization; Primary and secondary microseisms; Seismology.
Ano: 2011 URL: http://archimer.ifremer.fr/doc/00041/15219/12713.pdf
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Modelling long-term seismic noise in various environments ArchiMer
Stutzmann, E.; Ardhuin, Fabrice; Schimmel, M.; Mangeney, A.; Patau, G..
The strongest seismic noise, called secondary microseisms, is generated by ocean wave interactions and we model this noise using the theory of Longuet-Higgins generalized to random ocean gravity waves. Noise sources are computed with an ocean wave model that takes into account coastal reflections. Variations of the source locations are consistent with seasonal variations of seismic noise spectra. Noise spectra are modelled over many years for stations representative of various environments such as continent, island and polar area to constrain, for each environment, the parameters involved in the modelling. For each station, we quantify the trade-off between ocean wave coastal reflection and seismic wave attenuation that both affect the amplitude of the...
Tipo: Text Palavras-chave: Surface waves and free oscillations; Theoretical seismology; Wave propagation.
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00107/21839/19436.pdf
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Sensitivity to wind stress formulation in a coupled wave-atmosphere model ArchiMer
Pineau-guillou, Lucia; Ardhuin, Fabrice; Bouin, Marie-noëlle; Redelsperger, Jean-luc; Chapron, Bertrand; Bidlot, Jean.
Tipo: Text
Ano: 2016 URL: http://archimer.ifremer.fr/doc/00350/46095/45768.pdf
Registros recuperados: 129
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