Time Series of Near‐Inertial Gravity Wave Energy Fluxes: The Effect of a Strong Wind Event

This paper addresses the sizing problem of an energy storage system (ESS) while considering statistical tolerance for a two-body wave energy converter (WEC), which is designed to support ocean sensing applications with sustained power for long-term functioning. The power is extracted by assuming ideal power take-off (PTO) based upon historical ocean data record (significant wave height and period of wave swell) from Martha’s Vineyard Coastal Observatory. A gamma distribution is applied to generate the extracted power distribution of each sample in the time-series using Bayesian methodology. The means and standard deviation of the extracted power distributions compose the statistical annual power time-series. Finally, the required capacities for the ESS sizing are estimated and discussed while considering both ground truth values and statistical values.

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A statistical study of gravity waves from radiosonde observations at Wuhan (30° N, 114° E) China

Annales Geophysicae ◽

10.5194/angeo-23-665-2005 ◽

2005 ◽

Vol 23 (3) ◽

pp. 665-673 ◽

Cited By ~ 37

Author(s):

S. D. Zhang ◽

F. Yi

Keyword(s):

Gravity Wave ◽

Gravity Waves ◽

Extreme Values ◽

Dynamical Instability ◽

Strong Wind ◽

Data Set ◽

Height Range ◽

Wave Parameters ◽

Thermal Structures ◽

Radiosonde Observation

Abstract. Several works concerning the dynamical and thermal structures and inertial gravity wave activities in the troposphere and lower stratosphere (TLS) from the radiosonde observation have been reported before, but these works were concentrated on either equatorial or polar regions. In this paper, background atmosphere and gravity wave activities in the TLS over Wuhan (30° N, 114° E) (a medium latitudinal region) were statistically studied by using the data from radiosonde observations on a twice daily basis at 08:00 and 20:00 LT in the period between 2000 and 2002. The monthly-averaged temperature and horizontal winds exhibit the essential dynamic and thermal structures of the background atmosphere. For avoiding the extreme values of background winds and temperature in the height range of 11-18km, we studied gravity waves, respectively, in two separate height regions, one is from ground surface to 10km (lower part), and the other is within 18-25km (upper part). In total, 791 and 1165 quasi-monochromatic inertial gravity waves were extracted from our data set for the lower and upper parts, respectively. The gravity wave parameters (intrinsic frequencies, amplitudes, wavelengths, intrinsic phase velocities and wave energies) are calculated and statistically studied. The statistical results revealed that in the lower part, there were 49.4% of gravity waves propagating upward, and the percentage was 76.4% in the upper part. Moreover, the average wave amplitudes and energies are less than those at the lower latitudinal regions, which indicates that the gravity wave parameters have a latitudinal dependence. The correlated temporal evolution of the monthly-averaged wave energies in the lower and upper parts and a subsequent quantitative analysis strongly suggested that at the observation site, dynamical instability (strong wind shear) induced by the tropospheric jet is the main excitation source of inertial gravity waves in the TLS.

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Short-term changes in the mesozooplankton community and copepod gut pigment in the Chukchi Sea in autumn: reflections of a strong wind event

Biogeosciences ◽

10.5194/bg-12-4005-2015 ◽

2015 ◽

Vol 12 (13) ◽

pp. 4005-4015 ◽

Cited By ~ 8

Author(s):

K. Matsuno ◽

A. Yamaguchi ◽

S. Nishino ◽

J. Inoue ◽

T. Kikuchi

Keyword(s):

Atmospheric Turbulence ◽

Chukchi Sea ◽

Strong Wind ◽

Calanoid Copepods ◽

Mesozooplankton Community ◽

Chl A ◽

Wind Event ◽

Food Requirement ◽

Copepodid Stage ◽

Gut Pigment

Abstract. To evaluate the effect of atmospheric turbulence on a marine ecosystem, high-frequency samplings (two to four times per day) of a mesozooplankton community and the gut pigment of dominant copepods were performed at a fixed station in the Chukchi Sea from 10 to 25 September 2013. During the study period, a strong wind event (SWE) was observed on 18 September. After the SWE, the biomass of chlorophyll a (Chl a) increased, especially for micro-size (> 10 μm) fractions. The zooplankton abundance ranged from 23 610 to 56 809 ind. m−2 and exhibited no clear changes as a result of the SWE. In terms of abundance, calanoid copepods constituted the dominant taxa (mean: 57 %), followed by barnacle larvae (31 %). Within the calanoid copepods, small-sized Pseudocalanus spp. (65 %) and large-sized C. glacialis (30 %) dominated. In the population structure of C. glacialis, copepodid stage 5 (C5) dominated, and the mean copepodid stage did not vary with the SWE. The dominance of accumulated lipids in C5 and C6 females with immature gonads indicated that they were preparing for seasonal diapause. The gut pigment of C. glacialis C5 was higher at night and was correlated with ambient Chl a (Chl a, and a significant increase was observed after the SWE (2.6 vs. 4.5 ng pigment ind.−1). The grazing impact by C. glacialis C5 was estimated to be 4.14 mg C m−2 day−1, which corresponded to 0.5−4.6 % of the biomass of the micro-size phytoplankton. Compared with the metabolic food requirement, C. glacialis feeding on phytoplankton accounted for 12.6 % of their total food requirement. These facts suggest that C. glacialis could not maintain their population by feeding solely on phytoplankton and that other food sources (i.e., microzooplankton) must be important in autumn. As observed by the increase in gut pigment, the temporal phytoplankton bloom, which is enhanced by the atmospheric turbulence (SWE) in autumn, may have a positive effect on copepod nutrition.

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Seasonal variations in lower stratospheric gravity wave energy above the Falkland Islands

Journal of Geophysical Research Atmospheres ◽

10.1002/jgrd.50859 ◽

2013 ◽

Vol 118 (19) ◽

pp. 10,861-10,869 ◽

Cited By ~ 15

Author(s):

T. Moffat-Griffin ◽

M. J. Jarvis ◽

S. R. Colwell ◽

A. J. Kavanagh ◽

G. L. Manney ◽

...

Keyword(s):

Gravity Wave ◽

Wave Energy ◽

Seasonal Variations ◽

Falkland Islands

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Identification and Modeling Carbon and Energy Fluxes from Eddy Covariance Time Series Measurements in Rice and Rainfed Crops

Engineering Proceedings ◽

10.3390/engproc2021009009 ◽

2021 ◽

Vol 9 (1) ◽

pp. 9

Author(s):

Víctor Cicuéndez ◽

Javier Litago ◽

Víctor Sánchez-Girón ◽

Laura Recuero ◽

César Sáenz ◽

...

Keyword(s):

Time Series ◽

Time Series Analysis ◽

Primary Production ◽

Eddy Covariance ◽

Carbon Balance ◽

Gross Primary Production ◽

Meteorological Variables ◽

Water Fluxes ◽

Energy Fluxes ◽

Global Carbon

Gross primary production (GPP) represents the carbon (C) uptake of ecosystems through photosynthesis and it is the largest flux of the global carbon balance. Our overall objective in this research is to identify and model GPP dynamics and its relationship with meteorological variables and energy fluxes based on time series analysis of eddy covariance (EC) data in two different agroecosystems, a Mediterranean rice crop in Spain and a rainfed cropland in Germany. Crops exerted an important influence on the energy and water fluxes dynamics existing a clear feedback between GPP, meteorological variables and energy fluxes in both type of crops.

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Momentum and Energy Transport by Gravity Waves in Stochastically Driven Stratified Flows. Part I: Radiation of Gravity Waves from a Shear Layer

Journal of the Atmospheric Sciences ◽

10.1175/jas3905.1 ◽

2007 ◽

Vol 64 (5) ◽

pp. 1509-1529 ◽

Cited By ~ 10

Author(s):

Nikolaos A. Bakas ◽

Petros J. Ioannou

Keyword(s):

Shear Flow ◽

Shear Layer ◽

Gravity Wave ◽

Gravity Waves ◽

Wave Energy ◽

Energy Transport ◽

Wave Spectrum ◽

Internal Gravity Waves ◽

Wave Interference ◽

Wide Range

Abstract In this paper, the emission of internal gravity waves from a local westerly shear layer is studied. Thermal and/or vorticity forcing of the shear layer with a wide range of frequencies and scales can lead to strong emission of gravity waves in the region exterior to the shear layer. The shear flow not only passively filters and refracts the emitted wave spectrum, but also actively participates in the gravity wave emission in conjunction with the distributed forcing. This interaction leads to enhanced radiated momentum fluxes but more importantly to enhanced gravity wave energy fluxes. This enhanced emission power can be traced to the nonnormal growth of the perturbations in the shear region, that is, to the transfer of the kinetic energy of the mean shear flow to the emitted gravity waves. The emitted wave energy flux increases with shear and can become as large as 30 times greater than the corresponding flux emitted in the absence of a localized shear region. Waves that have horizontal wavelengths larger than the depth of the shear layer radiate easterly momentum away, whereas the shorter waves are trapped in the shear region and deposit their momentum at their critical levels. The observed spectrum, as well as the physical mechanisms influencing the spectrum such as wave interference and Doppler shifting effects, is discussed. While for large Richardson numbers there is equipartition of momentum among a wide range of frequencies, most of the energy is found to be carried by waves having vertical wavelengths in a narrow band around the value of twice the depth of the region. It is shown that the waves that are emitted from the shear region have vertical wavelengths of the size of the shear region.

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A numerical simulation of a strong wind event in January 2013 at King Sejong station, Antarctica

Quarterly Journal of the Royal Meteorological Society ◽

10.1002/qj.3496 ◽

2019 ◽

Vol 145 (720) ◽

pp. 1267-1280

Author(s):

Hataek Kwon ◽

Sang‐Jong Park ◽

Solji Lee ◽

Baek‐Min Kim ◽

Taejin Choi ◽

...

Keyword(s):

Numerical Simulation ◽

Strong Wind ◽

Wind Event

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Case Study of a Barrier Wind Corner Jet off the Coast of the Prince Olav Mountains, Antarctica

Monthly Weather Review ◽

10.1175/mwr-d-11-00261.1 ◽

2012 ◽

Vol 140 (7) ◽

pp. 2044-2063 ◽

Cited By ~ 25

Author(s):

Melissa A. Nigro ◽

John J. Cassano ◽

Matthew A. Lazzara ◽

Linda M. Keller

Keyword(s):

Strong Wind ◽

Ice Shelf ◽

Maximum Wind ◽

Ross Ice Shelf ◽

Wind Speeds ◽

Wind Event ◽

Transantarctic Mountains ◽

Upper Level ◽

Forcing Mechanisms

Abstract The Ross Ice Shelf airstream (RAS) is a barrier parallel flow along the base of the Transantarctic Mountains. Previous research has hypothesized that a combination of katabatic flow, barrier winds, and mesoscale and synoptic-scale cyclones drive the RAS. Within the RAS, an area of maximum wind speed is located to the northwest of the protruding Prince Olav Mountains. In this region, the Sabrina automatic weather station (AWS) observed a September 2009 high wind event with wind speeds in excess of 20 m s−1 for nearly 35 h. The following case study uses in situ AWS observations and output from the Antarctic Mesoscale Prediction System to demonstrate that the strong wind speeds during this event were caused by a combination of various forcing mechanisms, including katabatic winds, barrier winds, a surface mesocyclone over the Ross Ice Shelf, an upper-level ridge over the southern tip of the Ross Ice Shelf, and topographic influences from the Prince Olav Mountains. These forcing mechanisms induced a barrier wind corner jet to the northwest of the Prince Olav Mountains, explaining the maximum wind speeds observed in this region. The RAS wind speeds were strong enough to induce two additional barrier wind corner jets to the northwest of the Prince Olav Mountains, resulting in a triple barrier wind corner jet along the base of the Transantarctic Mountains.

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Sband Doppler radar measurements of bathymetry, wave energy fluxes, and dissipation across an offshore bar

Journal of Geophysical Research Atmospheres ◽

10.1029/98jc00447 ◽

1998 ◽

Vol 103 (C9) ◽

pp. 18779-18789 ◽

Cited By ~ 21

Author(s):

John A. McGregor ◽

E. Murray Poulter ◽

Murray J. Smith

Keyword(s):

Wave Energy ◽

Doppler Radar ◽

Energy Fluxes ◽

Radar Measurements

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