The interaction between waves and a turbulent current: waves propagating with the current

Kemp, Patrick H.; Simons, Richard R.

doi:10.1017/s0022112082000445

Cited by 317 publications

(183 citation statements)

References 9 publications

Supporting

Mentioning

164

Contrasting

Unclassified

Order By: Relevance

“…As the scatter of the data is significantly large, it is not possible to find any precise trend neither for the following or opposing waves and currents nor for the [1999] found that k s(w.c.) /k s(c.o.) increases with increasing U* 0 /u* f , it can be observed that an increasing trend is common only to the data of Kemp and Simons [1982], Kemp and Simons [1983], while the data of Mathisen and Madsen [1996] along with the present study show an Figure 14. Velocity profile in the current direction: current only over a flat bed (triangles); wave plus current over a flat bed (circles); current only over a rippled bed (stars); wave plus current over a rippled bed (pluses).…”

Section: Discussionsupporting

confidence: 46%

Waves plus currents at a right angle: The rippled bed case

2008

View full text Add to dashboard Cite

[1] The present paper deals with wave plus current flow over a fixed rippled bed. More precisely, modifications of the current profiles due to the superimposition of orthogonal cylindrical waves have been investigated experimentally. Since the experimental setup permitted only the wave dominated regime to be investigated (i.e., the regime where orbital velocity is larger than current velocity), also a numerical k-e turbulence closure model has been developed in order to study a wider range of parameters, thus including the current dominated regime (i.e., where current velocity is larger than wave orbital one). In both cases a different response with respect to the flat bed case has been found. Indeed, in the flat bed case laminar wave boundary layers in a wave dominated regime induce a decrease in bottom shear stresses, while the presence of a rippled bed behaves as a macroroughness, which causes the wave boundary layer to become turbulent and therefore the current velocity near the bottom to be smaller than the one in the case of current only, with a consequent increase in the current bottom roughness.

show abstract

Section: Discussionsupporting

confidence: 46%

Waves plus currents at a right angle: The rippled bed case

2008

View full text Add to dashboard Cite

show abstract

“…However, such corrections should be applied with caution here because part of the real vertical oxygen flux may be facilitated by wave motions and thus occur at the wave frequency. Wave motions over rough benthic surfaces can give rise to eddies or water parcel ejections at wave frequencies, which expand up into the bottom water, well above the wave boundary layer (Kemp and Simons, 1982;Sleath, 1987;Reidenbach et al, 2007).…”

Section: Discussionmentioning

confidence: 99%

Technical note: Time lag correction of aquatic eddy covariance data measured in the presence of waves

et al. 2015

View full text Add to dashboard Cite

Abstract. Extracting benthic oxygen fluxes from eddy covariance time series measured in the presence of surface gravity waves requires careful consideration of the temporal alignment of the vertical velocity and the oxygen concentration. Using a model based on linear wave theory and measured eddy covariance data, we show that a substantial error in flux can arise if these two variables are not aligned correctly in time. We refer to this error in flux as the time lag bias. In one example, produced with the wave model, we found that an offset of 0.25 s between the oxygen and the velocity data produced a 2-fold overestimation of the flux. In another example, relying on nighttime data measured over a seagrass meadow, a similar offset reversed the flux from an uptake of −50 mmol m −2 d −1 to a release of 40 mmol m −2 d −1 . The bias is most acute for data measured at shallow-water sites with short-period waves and low current velocities. At moderate or higher current velocities (> 5-10 cm s −1 ), the bias is usually insignificant. The widely used traditional time shift correction for data measured in unidirectional flows, where the maximum numerical flux is sought, should not be applied in the presence of waves because it tends to maximize the time lag bias or give unrealistic flux estimates. Based on wave model predictions and measured data, we propose a new time lag correction that minimizes the time lag bias. The correction requires that the time series of both vertical velocity and oxygen concentration contain a clear periodic wave signal. Because wave motions are often evident in eddy covariance data measured at shallow-water sites, we encourage more work on identifying new time lag corrections.

show abstract

“…Theories have been developed to explain how waves, through the action of radiation stresses (Longuet-Higgins and Stewart 1962), can drive along-shore currents on beaches. However, many laboratory experiments show other changes in mean flows when waves are superposed (see, e.g., Kemp and Simons 1982). Remarkably, Nepf (1992) found reductions in mean flow that nearly matched but were opposite in direction to the Stokes drift.…”

Section: Notesmentioning

confidence: 99%

A note on the potential transport of scalars and organisms by surface waves

Monismith

Fong

2004

Limnology & Oceanography

View full text Add to dashboard Cite

Wave‐induced transport that is not directly reflected in Eulerian current measurements, an effect known as Stokes drift, may play a significant role in the transport of organisms and solutes in the nearshore environment. Two sets of field observations are presented that illustrate the potential importance of wave‐induced transport. Velocities measured near Santa Barbara, California, are used to show that the theoretical Stokes drift can be stronger than measured Eulerian currents. Dye plume measurements made at Duck, North Carolina, in both wavy and nonwavy conditions indicate that wave‐induced scalar transport can be significant. To demonstrate the generality of these results, we present calculations of the Stokes drift for several depths and as functions of wave amplitude and period. Given that cross‐shore velocities typical of the nearshore coastal ocean are generally comparable to or smaller than these computed values of the Stokes drift, we conclude that observations and predictions of nearshore transport should include explicit consideration of wave‐induced transport.

show abstract

The interaction between waves and a turbulent current: waves propagating with the current

Cited by 317 publications

References 9 publications

Waves plus currents at a right angle: The rippled bed case

Waves plus currents at a right angle: The rippled bed case

Technical note: Time lag correction of aquatic eddy covariance data measured in the presence of waves

A note on the potential transport of scalars and organisms by surface waves

Contact Info

Product

Resources

About