Surface Wave Effects on the Translation of Wind Stress across the Air–Sea Interface in a Fetch-Limited, Coastal Embayment

AbstractThe role of surface gravity waves in structuring the air–sea momentum flux is examined in the middle reaches of Chesapeake Bay. Observed wave spectra showed that wave direction in Chesapeake Bay is strongly correlated with basin geometry. Waves preferentially developed in the direction of maximum fetch, suggesting that dominant wave frequencies may be commonly and persistently misaligned with local wind forcing. Direct observations from an ultrasonic anemometer and vertical array of ADVs show that the magnitude and direction of stress changed across the air–sea interface, suggesting that a stress divergence occurred at or near the water surface. Using a numerical wave model in combination with direct flux measurements, the air–sea momentum flux was partitioned between the surface wave field and the mean flow. Results indicate that the surface wave field can store or release a significant fraction of the total momentum flux depending on the direction of the wind. When wind blew across dominant fetch axes, the generation of short gravity waves stored as much as 40% of the total wind stress. Accounting for the storage of momentum in the surface wave field closed the air–sea momentum budget. Agreement between the direction of Lagrangian shear and the direction of the stress vector in the mixed surface layer suggests that the observed directional difference was due to the combined effect of breaking waves producing downward sweeps of momentum in the direction of wave propagation and the straining of that vorticity field in a manner similar to Langmuir turbulence.

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Application of the IDEMIX Concept for Internal Gravity Waves in the Atmosphere

Journal of the Atmospheric Sciences ◽

10.1175/jas-d-20-0107.1 ◽

2020 ◽

Vol 77 (10) ◽

pp. 3601-3618

Author(s):

B. Quinn ◽

C. Eden ◽

D. Olbers

Keyword(s):

Energy Balance ◽

Wave Field ◽

Gravity Wave ◽

Gravity Waves ◽

Momentum Flux ◽

Middle Atmosphere ◽

Internal Gravity Waves ◽

Wave Drag ◽

Mean Flow ◽

The Mean

AbstractThe model Internal Wave Dissipation, Energy and Mixing (IDEMIX) presents a novel way of parameterizing internal gravity waves in the atmosphere. IDEMIX is based on the spectral energy balance of the wave field and has previously been successfully developed as a model for diapycnal diffusivity, induced by internal gravity wave breaking in oceans. Applied here for the first time to atmospheric gravity waves, integration of the energy balance equation for a continuous wave field of a given spectrum, results in prognostic equations for the energy density of eastward and westward gravity waves. It includes their interaction with the mean flow, allowing for an evolving and local description of momentum flux and gravity wave drag. A saturation mechanism maintains the wave field within convective stability limits, and a closure for critical-layer effects controls how much wave flux propagates from the troposphere into the middle atmosphere. Offline comparisons to a traditional parameterization reveal increases in the wave momentum flux in the middle atmosphere due to the mean-flow interaction, resulting in a greater gravity wave drag at lower altitudes. Preliminary validation against observational data show good agreement with momentum fluxes.

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Momentum Flux Budget across the Air–Sea Interface under Uniform and Tropical Cyclone Winds

Journal of Physical Oceanography ◽

10.1175/2010jpo4299.1 ◽

2010 ◽

Vol 40 (10) ◽

pp. 2221-2242 ◽

Cited By ~ 15

Author(s):

Yalin Fan ◽

Isaac Ginis ◽

Tetsu Hara

Keyword(s):

Surface Wave ◽

Tropical Cyclone ◽

Wave Field ◽

Numerical Experiments ◽

Momentum Flux ◽

Translation Speed ◽

The Difference ◽

Surface Wave Field ◽

The Right ◽

Effect Of Surface

Abstract In coupled ocean–atmosphere models, it is usually assumed that the momentum flux into ocean currents is equal to the flux from air (wind stress). However, when the surface wave field grows (decays) in space or time, it gains (loses) momentum and reduces (increases) the momentum flux into subsurface currents compared to the flux from the wind. In particular, under tropical cyclone (TC) conditions the surface wave field is complex and fast varying in space and time and may significantly affect the momentum flux from wind into ocean. In this paper, numerical experiments are performed to investigate the momentum flux budget across the air–sea interface under both uniform and idealized TC winds. The wave fields are simulated using the WAVEWATCH III model. The difference between the momentum flux from wind and the flux into currents is estimated using an air–sea momentum flux budget model. In many of the experiments, the momentum flux into currents is significantly reduced relative to the flux from the wind. The percentage of this reduction depends on the choice of the drag coefficient parameterization and can be as large as 25%. For the TC cases, the reduction is mainly in the right-rear quadrant of the hurricane, and the percentage of the flux reduction is insensitive to the changes of the storm size and the asymmetry in the wind field but varies with the TC translation speed and the storm intensity. The results of this study suggest that it is important to explicitly resolve the effect of surface waves for accurate estimations of the momentum flux into currents under TCs.

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Numerical approach for analysis of surface wave field in the vicinity of caustics

2007 International Conference - Days on Diffraction ◽

10.1109/dd.2007.4531990 ◽

2007 ◽

Author(s):

M. A. Geyer ◽

T. B. Yanovskaya

Keyword(s):

Surface Wave ◽

Wave Field ◽

Numerical Approach ◽

Surface Wave Field

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Dynamic visual simulation of marine vector field based on LIC—a case study of surface wave field in typhoon condition

Journal of Oceanology and Limnology ◽

10.1007/s00343-019-8263-1 ◽

2019 ◽

Vol 37 (6) ◽

pp. 2025-2036 ◽

Cited By ~ 1

Author(s):

Zhendong Liu ◽

Haixing Liu ◽

Tianyun Su ◽

Zhen Jia ◽

Xinfang Li ◽

...

Keyword(s):

Vector Field ◽

Surface Wave ◽

Wave Field ◽

Visual Simulation ◽

Surface Wave Field

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Magnetostatic spin surface wave field visualization in YIG films

10.1117/12.364539 ◽

1999 ◽

Author(s):

Aleksei A. Klimov

Keyword(s):

Surface Wave ◽

Wave Field ◽

Surface Wave Field

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Monte-Carlo simulation studies of the nonlinear imaging of a two dimensional surface wave field by a synthetic aperture radar

International Journal of Remote Sensing ◽

10.1080/01431169008955125 ◽

1990 ◽

Vol 11 (10) ◽

pp. 1695-1727 ◽

Cited By ~ 87

Author(s):

CLAUS BRÜNING ◽

WERNER ALPERS ◽

KLAUS HASSELMANN

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Surface Wave ◽

Wave Field ◽

Synthetic Aperture ◽

Two Dimensional ◽

Simulation Studies ◽

Nonlinear Imaging ◽

Surface Wave Field ◽

Dimensional Surface

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Correlations between Ambient Noise and the Ocean Surface Wave Field

Journal of Physical Oceanography ◽

10.1175/1520-0485(1995)025<0513:cbanat>2.0.co;2 ◽

1995 ◽

Vol 25 (4) ◽

pp. 513-532 ◽

Cited By ~ 35

Author(s):

Francis C. Felizardo ◽

W. Kendall Melville

Keyword(s):

Surface Wave ◽

Wave Field ◽

Ambient Noise ◽

Ocean Surface ◽

Ocean Surface Wave ◽

Surface Wave Field

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Mesospheric gravity wave activity estimated via airglow imagery, multistatic meteor radar, and SABER data taken during the SIMONe–2018 campaign

10.5194/acp-2020-896 ◽

2020 ◽

Author(s):

Fabio Vargas ◽

Jorge L. Chau ◽

Harikrishnan Charuvil Asokan ◽

Michael Gerding

Keyword(s):

Gravity Waves ◽

Momentum Flux ◽

Large Scale ◽

Lower Thermosphere ◽

Small Scale ◽

Meteor Radar ◽

Mean Flow ◽

Horizontal Scale ◽

Momentum Fluxes ◽

Mesosphere And Lower Thermosphere

Abstract. We describe in this study the analysis of small and large horizontal scale gravity waves from datasets composed of images from multiple mesospheric nightglow emissions as well as multistatic specular meteor radar (MSMR) winds collected in early November 2018, during the SIMONe–2018 campaign. These ground-based measurements are supported by temperature and neutral density profiles from TIMED/SABER satellite in orbits near Kühlungsborn, northern Germany (54.1° N, 11.8° E). The scientific goals here include the characterization of gravity waves and their interaction with the mean flow in the mesosphere and lower thermosphere and their relationship to dynamical conditions in the lower and upper atmosphere. We obtain intrinsic parameters of small and large horizontal scale gravity waves and characterize their impact in the mesosphere region via momentum flux and flux divergence estimations. We have verified that a small percent of the detected wave events are responsible for most of the momentum flux measured during the campaign from oscillations seen in the airglow brightness and MSMR winds. From the analysis of small-scale gravity waves in airglow images, we have found wave momentum fluxes ranging from 0.38 to 24.74 m2/s2 (0.88 ± 0.73 m2/s2 on average), with a total of 586.96 m2/s2 (sum over all 362 detected waves). However, small horizontal scale waves with flux > 3 m2/s2 (11 % of the events) transport 50 % of the total measured flux. Likewise, wave events having flux > 10 m2/s2 (2 % of the events) transport 20 % of the total flux. The examination of two large-scale waves seen simultaneously in airglow keograms and MSMR winds revealed relative amplitudes > 35 %, which translates into momentum fluxes of 21.2–29.6 m/s. In terms of gravity wave–mean flow interactions, these high momentum flux waves could cause decelerations of 22–41 m/s/day (small-scale waves) and 38–43 m/s/day (large-scale waves) if breaking or dissipating within short distances in the mesosphere and lower thermosphere region. The dominant large-scale waves might be the result of secondary gravity excited from imbalanced flow in the stratosphere caused by primary wave breaking.

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Spectrally Resolved Energy Dissipation Rate and Momentum Flux of Breaking Waves

Journal of Physical Oceanography ◽

10.1175/2007jpo3762.1 ◽

2008 ◽

Vol 38 (6) ◽

pp. 1296-1312 ◽

Cited By ~ 77

Author(s):

Johannes R. Gemmrich ◽

Michael L. Banner ◽

Chris Garrett

Keyword(s):

Energy Dissipation ◽

Wave Field ◽

Wave Energy ◽

Dissipation Rate ◽

Momentum Flux ◽

Phase Speed ◽

Breaking Waves ◽

Energy Dissipation Rate ◽

Small Scale ◽

Breaking Wave

Abstract Video observations of the ocean surface taken from aboard the Research Platform FLIP reveal the distribution of the along-crest length and propagation velocity of breaking wave crests that generate visible whitecaps. The key quantity assessed is Λ(c)dc, the average length of breaking crests per unit area propagating with speeds in the range (c, c + dc). Independent of the wave field development, Λ(c) is found to peak at intermediate wave scales and to drop off sharply at larger and smaller scales. In developing seas breakers occur at a wide range of scales corresponding to phase speeds from about 0.1 cp to cp, where cp is the phase speed of the waves at the spectral peak. However, in developed seas, breaking is hardly observed at scales corresponding to phase speeds greater than 0.5 cp. The phase speed of the most frequent breakers shifts from 0.4 cp to 0.2 cp as the wave field develops. The occurrence of breakers at a particular scale as well as the rate of surface turnover are well correlated with the wave saturation. The fourth and fifth moments of Λ(c) are used to estimate breaking-wave-supported momentum fluxes, energy dissipation rate, and the fraction of momentum flux supported by air-entraining breaking waves. No indication of a Kolmogorov-type wave energy cascade was found; that is, there is no evidence that the wave energy dissipation is dominated by small-scale waves. The proportionality factor b linking breaking crest distributions to the energy dissipation rate is found to be (7 ± 3) × 10−5, much smaller than previous estimates.

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