Wave-Induced Stokes Drift Measurement by High-Frequency Radars: Preliminary Results

Mean drift currents due to spatially periodic surface waves in a viscous rotating fluid are investigated theoretically. The analysis is based on the Lagrangian description of motion. The fluid is homogeneous, the depth is infinite, and there is no continuous energy input at the surface. Owing to viscosity the wave field and the associated mass transport will attenuate in time. For the non-rotating case the present approach yields the time-decaying Stokes drift in a slightly viscous ocean. The analysis shows that the drift velocities are finite everywhere. In a rotating fluid it is found that the effect of viscosity implies a non-zero net mass transport associated with the waves, as opposed to the result of no net transport obtained from inviscid theory (Ursell 1950).

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Preliminary results of a novel enhancement method for high-frequency hearing loss

Computer Methods and Programs in Biomedicine ◽

10.1016/j.cmpb.2010.05.004 ◽

2011 ◽

Vol 102 (3) ◽

pp. 277-287 ◽

Cited By ~ 6

Author(s):

Umut Arioz ◽

Kemal Arda ◽

Umit Tuncel

Keyword(s):

Hearing Loss ◽

High Frequency ◽

High Frequency Hearing Loss ◽

Preliminary Results ◽

Enhancement Method

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ADCP Bias and Stokes Drift in AUV-Based Velocity Measurements

Journal of Atmospheric and Oceanic Technology ◽

10.1175/jtech-d-16-0182.1 ◽

2017 ◽

Vol 34 (9) ◽

pp. 2029-2042 ◽

Cited By ~ 2

Author(s):

André Amador ◽

Sergio Jaramillo ◽

Geno Pawlak

Keyword(s):

Wave Field ◽

Field Experiments ◽

Autonomous Underwater Vehicle ◽

Stokes Drift ◽

Linear Wave ◽

Velocity Measurements ◽

Adcp Measurements ◽

Local Wave ◽

Induced Velocity ◽

Wave Induced

AbstractA theoretical model is developed to describe how autonomous underwater vehicle (AUV)-based current measurements are influenced by a surface wave field. The model quantifies a quasi-Lagrangian, wave-induced velocity bias as a function of the local wave conditions, and the vehicle’s depth and velocity using a first-order expansion of the linear wave solution. The theoretical bias is verified via field experiments carried out off the coast of Oahu, Hawaii. Spatially averaged along- and cross-track AUV velocity measurements are calculated over one effective wavelength and compared with time-averaged, fixed ADCP measurements in a range of wave and current conditions. The wave-induced bias is calculated using wave directional spectra derived from fixed ADCP data. Ensemble-averaged velocity differences confirm the presence of the wave-induced bias O(1–5) cm s−1 and reveal an additional bias in the direction of the vehicle motion O(1) cm s−1. The analysis considers velocity measurements made using a Remote Environmental Monitoring Units (REMUS) 100 AUV, but the content applies to any small AUV (vehicle size wavelength) immersed in a wave field.

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Improvement of Drift Calculation in Mothy Operational Oil Spill Prediction System

International Oil Spill Conference Proceedings ◽

10.7901/2169-3358-2003-1-1067 ◽

2003 ◽

Vol 2003 (1) ◽

pp. 1067-1072 ◽

Cited By ~ 13

Author(s):

Pierre Daniel ◽

Fabien Marty ◽

Patrick Josse ◽

Chafih Skandrani ◽

Rachid Benshila

Keyword(s):

Oil Spill ◽

Large Scale ◽

Stokes Drift ◽

Vertical Shear ◽

Transport Modelling ◽

Meteorological Model ◽

Drift Model ◽

Linear Waves ◽

Wave Induced ◽

The Impact

ABSTRACT MOTHY (Modèle Océanique de Transport d'Hydrocarbures) is a pollutant drift model, developed and operated by Météo-France. MOTHY includes hydrodynamic coastal ocean modelling and real time atmospheric forcing from a global meteorological model. Pollutants can be oil or floating objects. To improve forecasts on the Mediterranean Sea, several methods were tested to inject large scale currents (permanent part) into the MOTHY system. The best results were obtained with monthly means of currents at 5 meters (from Mercator system). The addition of altimetric corrections improved the results. In addition the impact of wave (or swell) current, which is usually neglected in such models, is investigated. The literature has surprisingly little to say on the topic of wave-driven surface oil slicks. Earlier review on oil spill transport modelling includes wave driven transport among potential advection mechanisms. The discussion of wave-induced advection (mass transport) adopts a Lagrangian framework, focusing on the analyses of Stokes and Longuet-Higgins for the vertical profile of the Lagrangian velocity beneath waves. In our work, the action of a vertical shear due to waves is accounted for by including the Stokes drift due to weakly non linear waves. We evaluate this term and compare with observations of Erika pollution incident.

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