Wind-induced internal wave dynamics near the Adriatic shelf break

Leder, Nenad

doi:10.1016/s0278-4343(01)00077-2

Cited by 17 publications

(17 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In small interior seas, however, pycnoclines are commonly shallower and strongly influenced by riverine discharge, fetch of the basin, wind regimes and seasonal temperature changes, being sharper and shallower in summer time. In the Adriatic Sea, a small basin with riverine discharge, the halocline associated with the Po River has been documented to occur at around 10 m (Degobbis, 1989) and the thermocline at around 15 m (Leder, 2002) or between 7 m and 15 m (Herndl & Malacic, 1987). A pycnocline in the same area was identified by Malej et al.…”

Section: Discussionmentioning

confidence: 99%

Nummulitic banks in the upper Lutetian ‘Buil level’, Ainsa Basin, South Central Pyrenean Zone: the impact of internal waves

2011

View full text Add to dashboard Cite

Nummulites, a particularly abundant and diverse genus of larger benthonic foraminifera, formed huge accumulations (banks) during the Eocene, which are often good hydrocarbon reservoirs, especially in North Africa. Despite their economical interest, these accumulations are not well-understood and their origin is still under discussion. Reasons for this debate are the absence of living Nummulites accumulations and the high-variability of facies, including the size, shape and extension of the banks, which reflect the array of processes controlling sediment production and accumulation. The nummulitic banks near Santa María de Buil, in the Ainsa Basin (South Pyrenean Foreland Basin) are composed of recurrent facies associations within mappable bed units bounded by physical surfaces. The depositional processes that produced the Nummulites deshayesi accumulations are interpreted considering the shape of the banks, the type of bounding surfaces, the distribution of sedimentary textures, Nummulites test shapes and the associated skeletal components within the banks. This integrative analysis indicates that nummulitic banks accumulated from mass flows, with very poor sediment sorting. Textural and compositional differences among banks suggest that globose Nummulites thrived in the shallower part of the mesophotic zone with abundant nummulithoclasts, whereas flat nummulitic forms thrived in deeper mesophotic, clay-dominated settings. Interbedded with nummulitic banks, coral biostromes and coral mounds bearing Operculina, Discocyclina and Asterocyclina, represent in situ accumulation near the base of the photic zone. Internal waves (waves that propagate along the pycnocline) are thought to be the triggering mechanism for the density flows. Internal waves and induced bottom currents are sporadic but strong enough to bring sediments into suspension. In contrast to surface waves (both fair-weather and storm), whose impact is strongest near the sea surface and decreases with bathymetry, the impact of internal waves is usually strongest in the mid-shelf region and weaker in shallow water. This explains the compositional character of the nummulitic banks.

show abstract

Section: Discussionmentioning

confidence: 99%

Nummulitic banks in the upper Lutetian ‘Buil level’, Ainsa Basin, South Central Pyrenean Zone: the impact of internal waves

2011

View full text Add to dashboard Cite

show abstract

“…1), at the edge of the South Adriatic Pit (depths reaching more than 1200 m). In the shelf break area complex internal wave dynamics have been observed, not only at diurnal but at higher frequencies, as well (Leder, 2002). The topography between Lastovo and the South Adriatic Pit is characterized by a gradual slope between 100 and 200 m isobaths, and a more abrupt change further on.…”

Section: Methodsmentioning

confidence: 99%

“…However, U.S. Space Shuttle photographs of the southeastern Adriatic showed bright streaks due to tidal currents, as well as wave packets that could be surface expressions of internal tides . Diurnal temperature oscillations were noted in the analysis of short-term temperature and current measurements, which were carried out near the island of Lastovo in the summer of 1990 (Leder, 2002). Yet previously available time series were not long enough to enable a detailed study of the internal tides in the Adriatic.…”

Section: Sea Currents Recorded In Suruga Andmentioning

confidence: 99%

Diurnal internal tides detected in the Adriatic

2006

View full text Add to dashboard Cite

Abstract. Strong diurnal oscillations, documented by temperature data that were collected along a submarine cliff on the Lastovo Island (southern Adriatic), are studied and compared with sea level and wind measurements at Dubrovnik and Komiža (island of Vis). Three thermistors were deployed at the depths of 15, 22 and 36 m between March 2001 and March 2002. Pronounced diurnal temperature oscillations were detected at 15 and 22 m during the stratified season. The correlation between the sea surface and thermocline displacements was highest in June 2001, when diurnal wind changes were not significant, while diurnal sea level oscillations achieved annual maxima. Thermocline oscillations were in phase with sea level changes. The range of diurnal sea surface variability was close to 19 cm, while the range of corresponding thermocline variability was about 5.4 m. The findings summarize the outcome of the first dedicated study of internal tides in the Adriatic.

show abstract

“…Wunsch andWebb (1979), D'Asaro andPerkins (1984), Levine et al (1985) extended their work to some special sea areas where the GM or IWEX models do not fit well. Leder (2002) examined the spectra of internal wave currents and temperature near the Adriatic shelf break in response to a strong wind.…”

Section: Spectrum Characteristics and Typhoon Influencementioning

confidence: 99%

Response of internal waves to 2005 Typhoon Damrey over the northwestern shelf of the South China Sea

Wang

Hou

Dai³

et al. 2008

J. Ocean Univ. China

View full text Add to dashboard Cite

Continuous observation of sea water temperature and current was made at Wenchang Station (19˚35′N, 112˚E) in 2005. The data collected indicate vigorous internal waves of both short periods and tidal and near-inertial periods. The temperature and current time series during 18-30 September were examined to describe the upper ocean internal wave field response to Typhoon Damrey (0518). The strong wind associated with the typhoon, which passed over the sea area about 45 km south of Wenchang Station on 25 September, deepened the mixed layer depth remarkably. It decreased the mixed layer temperature while increasing the deep layer temperature, and intensified the near-inertial and high-frequency fluctuations of temperature and current. Power spectra of temperature and current time series indicate significant deviations from those obtained by using the deep ocean internal wave models characterized by a power law. The frequency spectra were dominated by three energetic bands: around the inertial frequency (7.75× 10 -6 Hz), tidal frequencies (1.0×10 -5 to 2.4×10 -5 Hz), and between 1.4×10 -4 and 8.3×10 -4 Hz. Dividing the field data into three phases (before, during and after the typhoon), we found that the typhoon enhanced the kinetic energy in nearly all the frequency bands, especially in the surface water. The passage of Damrey made a major contribution to the horizontal kinetic energy of the total surface current variances. The vertical energy density distribution, with its peak value at the surface, was an indication that the energy injected by the strong wind into the surface current could penetrate downward to the thermocline.

show abstract

Wind-induced internal wave dynamics near the Adriatic shelf break

Cited by 17 publications

References 27 publications

Nummulitic banks in the upper Lutetian ‘Buil level’, Ainsa Basin, South Central Pyrenean Zone: the impact of internal waves

Nummulitic banks in the upper Lutetian ‘Buil level’, Ainsa Basin, South Central Pyrenean Zone: the impact of internal waves

Diurnal internal tides detected in the Adriatic

Response of internal waves to 2005 Typhoon Damrey over the northwestern shelf of the South China Sea

Contact Info

Product

Resources

About