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A surface kinematics buoy (SKIB) for wave–current interaction studies ArchiMer
Veras Guimaraes, Pedro; Ardhuin, Fabrice; Sutherland, Peter; Accensi, Mickael; Hamon, Michel; Perignon, Yves; Thomson, Jim; Benetazzo, Alvise; Ferrant, Pierre.
Global navigation satellite systems (GNSSs) and modern motion-sensor packages allow the measurement of ocean surface waves with low-cost drifters. Drifting along or across current gradients provides unique measurements of wave–current interactions. In this study, we investigate the response of several combinations of GNSS receiver, motion-sensor package and hull design in order to define a prototype “surface kinematics buoy” (SKIB) that is particularly optimized for measuring wave–current interactions, including relatively short wave components that are important for air–sea interactions and remote-sensing applications. The comparison with existing Datawell Directional Waverider and Surface Wave Instrument Float with Tracking (SWIFT) buoys, as well as...
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Ano: 2018 URL: https://archimer.ifremer.fr/doc/00470/58136/60605.pdf
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Airborne remote sensing of ocean wave directional wavenumber spectra in the marginal ice zone ArchiMer
Sutherland, Peter; Gascard, Jean-claude.
Interactions between surface waves and sea ice are thought to be an important, but poorly understood, physical process in the atmosphere-ice-ocean system. In this work, airborne scanning lidar was used to observe ocean waves propagating into the marginal ice zone (MIZ). These represent the first direct spatial measurements of the surface wave field in the polar MIZ. Data were compared against two attenuation models, one based on viscous dissipation and one based on scattering. Both models were capable of reproducing the measured wave energy. The observed wavenumber dependence of attenuation was found to be consistent with viscous processes, while the spectral spreading of higher wavenumbers suggested a scattering mechanism. Both models reproduced a change...
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Ano: 2016 URL: http://archimer.ifremer.fr/doc/00333/44454/44125.pdf
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Airborne Remote Sensing of Wave Propagation in the Marginal Ice Zone ArchiMer
Sutherland, Peter; Brozena, John; Rogers, W. Erick; Doble, Martin; Wadhams, Peter.
Airborne scanning lidar was used to measure the evolution of the surface wave field in the marginal ice zone (MIZ) during two separate wave events in the Beaufort Sea in October 2015. The lidar data consisted of a 2‐D field of surface elevation with horizontal resolutions between 17 and 33 cm, over a swath approximately 150‐220 m wide, centred on the ground track of the aircraft. Those data were used to compute directional wavenumber spectra of the surface wave field. Comparison with nearly collocated buoy data found the lidar and buoy measurements to be generally consistent. During the first event, waves travelling from open water into the ice were attenuated by the ice. The low spectral spreading and k7/4 spectral dependence of the attenuation was...
Tipo: Text Palavras-chave: Surface waves; Marginal ice zone; Wave attenuation; Wave growth rate; Air-sea-ice; Airborne scanning lidar.
Ano: 2018 URL: https://archimer.ifremer.fr/doc/00439/55086/56526.pdf
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Laboratory Experiments on Internal Solitary Waves in Ice‐Covered Waters ArchiMer
Carr, Magda; Sutherland, Peter; Haase, Andrea; Evers, Karl‐ulrich; Fer, Ilker; Jensen, Atle; Kalisch, Henrik; Berntsen, Jarle; Părău, Emilian; Thiem, Øyvind; Davies, Peter.
Internal solitary waves (ISWs) propagating in a stably stratified two-layer fluid in which the upper boundary condition changes from open water to ice are studied for grease, level, and nilas ice. The ISW-induced current at the surface is capable of transporting the ice in the horizontal direction. In the level ice case, the transport speed of, relatively long ice floes, nondimensionalized by the wave speed is linearly dependent on the length of the ice floe nondimensionalized by the wave length. Measures of turbulent kinetic energy dissipation under the ice are comparable to those at the wave density interface. Moreover, in cases where the ice floe protrudes into the pycnocline, interaction with the ice edge can cause the ISW to break or even be destroyed...
Tipo: Text Palavras-chave: Internal solitary waves; Sea ice; Arctic Ocean.
Ano: 2019 URL: https://archimer.ifremer.fr/doc/00593/70532/68677.pdf
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Marginal ice zone thickness and extent due to wave radiation stress. ArchiMer
Sutherland, Peter; Dumont, Dany.
Ocean surface wave radiation stress represents the flux of momentum due to the waves. When waves are dissipated or reflected by sea ice, that momentum is absorbed or reflected, resulting in a horizontal forcing which frequently compresses the ice. In this work, wave radiation stress is used to estimate the compressive force applied by waves to the marginal ice zone (MIZ). It is balanced by an ice internal compressive stress based on Mohr-Coulomb granular materials theory. The ice internal stress can be related to ice thickness, allowing this force balance to be used as a model for the estimation of MIZ ice thickness. The model was validated and tested using data collected during two field campaigns in the St. Lawrence Estuary in 2016 and 2017. Modelled ice...
Tipo: Text Palavras-chave: Sea ice; Momentum; Waves; Oceanic; Ice thickness.
Ano: 2018 URL: https://archimer.ifremer.fr/doc/00448/55994/57486.pdf
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Observations of Near-Surface Current Shear Help Describe Oceanic Oil and Plastic Transport ArchiMer
Laxague, Nathan J. M.; Ozgokmen, Tamay M.; Haus, Brian K.; Novelli, Guillaume; Shcherbina, Andrey; Sutherland, Peter; Guigand, Cedric M.; Lund, Bjorn; Mehta, Sanchit; Alday, Matias; Molemaker, Jeroen.
Plastics and spilled oil pose a critical threat to marine life and human health. As a result of wind forcing and wave motions, theoretical and laboratory studies predict very strong velocity variation with depth over the upper few centimeters of the water column, an observational blind spot in the real ocean. Here we present the first-ever ocean measurements of the current vector profile defined to within 1 cm of the free surface. In our illustrative example, the current magnitude averaged over the upper 1 cm of the ocean is shown to be nearly four times the average over the upper 10 m, even for mild forcing. Our findings indicate that this shear will rapidly separate pieces of marine debris which vary in size or buoyancy, making consideration of these...
Tipo: Text Palavras-chave: Ocean current shear; Near-surface currents; Marine plastics; Spilled oil; Lagrangian transport.
Ano: 2018 URL: http://archimer.ifremer.fr/doc/00425/53614/54443.pdf
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Ocean waves across the Arctic: attenuation due to dissipation dominates over scattering for periods longer than 19 s ArchiMer
Ardhuin, Fabrice; Sutherland, Peter; Doble, Martin; Wadhams, Peter.
The poorly understood attenuation of surface waves in sea ice is generally attributed to the combination of scattering and dissipation. Scattering and dissipation have very different effects on the directional and temporal distribution of wave energy, making it possible to better understand their relative importance by analysis of swell directional spreading and arrival times. Here we compare results of a spectral wave model – using adjustable scattering and dissipation attenuation formulations – with wave measurements far inside the ice pack. In this case, scattering plays a negligible role in the attenuation of long swells. Specifically, scattering-dominated attenuation would produce directional wave spectra much broader than the ones recorded, and swell...
Tipo: Text Palavras-chave: Ocean waves; Sea ice; Tara; DAMOCLES.
Ano: 2016 URL: http://archimer.ifremer.fr/doc/00333/44455/44127.pdf
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Overview of the Arctic Sea State and Boundary Layer Physics Program ArchiMer
Thomson, Jim; Ackley, Stephen; Girard-ardhuin, Fanny; Ardhuin, Fabrice; Babanin, Alex; Boutin, Guillaume; Brozena, John; Cheng, Sukun; Collins, Clarence; Doble, Martin; Fairall, Chris; Guest, Peter; Gebhardt, Claus; Gemmrich, Johannes; Graber, Hans C.; Holt, Benjamin; Lehner, Susanne; Lund, Bjorn; Meylan, Michael H.; Maksym, Ted; Montiel, Fabien; Perrie, Will; Persson, Ola; Rainville, Luc; Rogers, W. Erick; Shen, Hui; Shen, Hayley; Squire, Vernon; Stammerjohn, Sharon; Stopa, Justin; Smith, Madison M.; Sutherland, Peter; Wadhams, Peter.
A large collaborative program has studied the coupled air‐ice‐ocean‐wave processes occurring in the Arctic during the autumn ice advance. The program included a field campaign in the western Arctic during the autumn of 2015, with in situ data collection and both aerial and satellite remote sensing. Many of the analyses have focused on using and improving forecast models. Summarizing and synthesizing the results from a series of separate papers, the overall view is of an Arctic shifting to a more seasonal system. The dramatic increase in open water extent and duration in the autumn means that large surface waves and significant surface heat fluxes are now common. When refreezing finally does occur, it is a highly variable process in space and time. Wind and...
Tipo: Text Palavras-chave: Arctic; Waves; Autumn; Sea ice; Beaufort; Flux.
Ano: 2018 URL: https://archimer.ifremer.fr/doc/00437/54837/56313.pdf
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Stereo imaging and X-band radar wave data fusion: An assessment ArchiMer
Benetazzo, Alvise; Serafino, Francesco; Bergamasco, Filippo; Ludeno, Giovanni; Ardhuin, Fabrice; Sutherland, Peter; Sclavo, Mauro; Barbariol, Francesco.
The use of spatial and spatio-temporal data is rapidly changing the paradigm of wind wave observations, which have been traditionally restricted to time series from single-point measurements (e.g. from buoys, wave gauges). Active and passive 2D remote sensors mounted on platforms, ships, airplanes and satellites are now becoming standards in the oceanographic community and industry. Given the covered area ranging from centimeters to kilometers, such sensors are now a valuable tool for ocean and coastal observations. In this paper, we intercompare spatio-temporal wind wave data acquired with two state-of-the-art techniques, namely the stereo wave imaging and the X-band marine radar. The comparison was performed by operating the two instruments on an...
Tipo: Text Palavras-chave: Directional wave observations; Stereo wave imaging; X-band marine radar; Modulation Transfer Function (MTF); Sea technology.
Ano: 2018 URL: https://archimer.ifremer.fr/doc/00428/53934/55108.pdf
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Strong and highly variable push of ocean waves on Southern Ocean sea ice ArchiMer
Stopa, Justin; Sutherland, Peter; Ardhuin, Fabrice.
Sea ice in the Southern Ocean has expanded over most of the past 20 y, but the decline in sea ice since 2016 has taken experts by surprise. This recent evolution highlights the poor performance of numerical models for predicting extent and thickness, which is due to our poor understanding of ice dynamics. Ocean waves are known to play an important role in ice break-up and formation. In addition, as ocean waves decay, they cause a stress that pushes the ice in the direction of wave propagation. This wave stress could not previously be quantified due to insufficient observations at large scales. Sentinel-1 synthetic aperture radars (SARs) provide high-resolution imagery from which wave height is measured year round encompassing Antarctica since 2014. Our...
Tipo: Text Palavras-chave: Wave-ice interaction; Southern Ocean marginal ice zone; Wave radiation stress; Sentinel-1 SAR; Synthetic aperture radar.
Ano: 2018 URL: https://archimer.ifremer.fr/doc/00444/55609/57255.pdf
Registros recuperados: 10
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