Field data support of three-seconds power law andgu *σ−4-spectral form for growing wind waves

1977 ◽  
Vol 33 (3) ◽  
pp. 137-150 ◽  
Author(s):  
Sanshiro Kawai ◽  
Kozo Okada ◽  
Yoshiaki Toba
Keyword(s):  
Power Law ◽  
Field Data ◽  
Wind Waves ◽  
Spectral Form ◽  
Data Support

Geology and petrochemistry of lower Aphebian (2.4–2.0 Ga) alkaline plutonic and hypabyssal rocks in the East Arm of Great Slave Lake, Northwest Territories

1979 ◽  
Vol 16 (1) ◽  
pp. 60-72 ◽  
Author(s):  
J. P. N. Badham
Keyword(s):  
Northwest Territories ◽  
Field Data ◽  
Easter Island ◽  
Chemical Data ◽  
Lower Proterozoic ◽  
Great Slave Lake ◽  
Data Support ◽  
Igneous Complexes ◽  
Igneous Activity ◽  
History Of

Two alkaline igneous complexes and three lines of diatreme breccias were emplaced in the East Arm of Great Slave Lake during the lower Proterozoic. Field relationships suggest that those rocks are broadly cogenetic and were emplaced about 2.1 Ga ago.One of the intrusions, the Easter Island dyke, was rotated subsequent to emplacement such that both top and bottom are now exposed. Field and petrographic data are indicative of progressive differentiation along (i.e., up) the dyke and are substantiated by chemical data. The differentiation history of the early gabbros of the Blachford Lake complex is similar. Late differentiates of both complexes closely resemble the igneous matrices of the breccias and petrographic and chemical data support the proposal of cogenesis and contemporaneity.The field data show that there was a period of significant faulting and concomitant alkaline igneous activity in the East Arm area in the lower Proterozoic.

scholarly journals Experimental and Field Data Support Range Expansion in an Allopolyploid Arabidopsis Owing to Parental Legacy of Heavy Metal Hyperaccumulation

2020 ◽  
Vol 11 ◽  
Author(s):  
Timothy Paape ◽  
Reiko Akiyama ◽  
Teo Cereghetti ◽  
Yoshihiko Onda ◽  
Akira S. Hirao ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Range Expansion ◽  
Field Data ◽  
Metal Hyperaccumulation ◽  
Data Support

scholarly journals Wind Wave Growth at Short Fetch

2008 ◽  
Vol 38 (7) ◽  
pp. 1597-1606 ◽  
Author(s):  
T. Lamont-Smith ◽  
T. Waseda
Keyword(s):  
Wind Speed ◽  
Wave Height ◽  
Significant Wave Height ◽  
Field Data ◽  
Wind Wave ◽  
Wind Waves ◽  
Retention Rates ◽  
Horizontal Distance ◽  
Wave Tank ◽  
Significant Wave

Abstract Wave wire data from the large wind wave tank of the Ocean Engineering Laboratory at the University of California, Santa Barbara, are analyzed, and comparisons are made with published data collected in four other wave tanks. The behavior of wind waves at various fetches (7–80 m) is very similar to the behavior observed in the other tanks. When the nondimensional frequency F* or nondimensional significant wave height H* is plotted against nondimensional fetch x*, a large scatter in the data points is found. Multivariate regression to the dimensional parameters shows that significant wave height Hsig is a function of U2x and frequency F is a function of U1.25x, where U is the wind speed and x is the horizontal distance, with the result that in general for wind waves at a particular fetch in a wave tank, approximately speaking, the wave frequency is inversely proportional to the square root of the wind speed and the wavelength is proportional to the wind speed. Similarly, the wave height is proportional to U1.5 and the orbital velocity is proportional to U. Comparison with field data indicates a transition from this fetch law to the conventional one [the Joint North Sea Wave Project (JONSWAP)] for longer fetch. Despite differences in the fetch relationship for the wave tank and the field data, the wave height and wave period satisfy Toba’s 3/2 power law. This law imposes a strong constraint on the evolution of wind wave energy and frequency; consequently, the energy and momentum retention rate are not independent. Both retention rates grow with wind speed and fetch at the short fetches present in the wave tank. The observed retention rates are completely different from those typically observed in the field, but the same constraint (Toba’s 3/2 law) holds true.

Multidecadal Field Data Support Intimate Links between Phytoplankton Dynamics and PCB Concentrations in Marine Sediments and Biota

2015 ◽  
Vol 49 (14) ◽  
pp. 8704-8711 ◽  
Author(s):  
Gert Everaert ◽  
Frederik De Laender ◽  
Peter L. M. Goethals ◽  
Colin R. Janssen
Keyword(s):  
Marine Sediments ◽  
Field Data ◽  
Phytoplankton Dynamics ◽  
Data Support

scholarly journals Coastline evolution based on statistical analysis and modelling

2018 ◽  
Author(s):  
Elvira Armenio ◽  
Francesca De Serio ◽  
Michele Mossa ◽  
Antonio F. Petrillo
Keyword(s):  
Statistical Analysis ◽  
Numerical Modelling ◽  
Field Data ◽  
Wind Waves ◽  
Management Strategies ◽  
Coastal Zone Management ◽  
Sediment Supply ◽  
Aerial Photographs ◽  
Joint Analysis ◽  
Coastal System

Abstract. Wind, waves, tides, sediment supply, changes in relative sea level and human activities strongly affect shorelines, which constantly move in response to these processes, over a variety of time scales. Thus, the implementation of sound coastal zone management strategies needs reliable information on erosion and/or deposition processes. Suggesting a feasible way to provide such information is the main motivation of the present work. A chain approach is here proposed, tested on a vulnerable coastal site located along the southern Italy, and based on the joint analysis of field data, statistical tools and numerical modelling. Firstly, the coastline morphology has been examined through interannual field data, such as aerial photographs, plane-bathymetric surveys, seabed characterization. After this, rates of shoreline changes have been quantified with a specific GIS tool. Correlations among the historical shoreline positions have been detected by statistical analysis and have been satisfactorily confirmed by numerical modelling, in terms of recurrent erosion/accretion area and beach rotation trends. Finally, based on field topographic, sediment, wave and wind data, the response of the beach by the numerical simulation has been investigated in a forecasting perspective. The scope of this study is providing a feasible, general and replicable chain approach, which could help to thoroughly understand the dynamics of a coastal system, identifying typical and recurrent erosion/accretion processes, and predict possible future trends, useful for planning coastal activities.

How can blind tiger snakes (Notechis scutatus) forage successfully?

2005 ◽  
Vol 53 (5) ◽  
pp. 283
Author(s):  
Fabien Aubret ◽  
Xavier Bonnet ◽  
David Pearson ◽  
Richard Shine
Keyword(s):  
Western Australia ◽  
Fast Moving ◽  
Field Data ◽  
Great Difficulty ◽  
Small Island ◽  
Surprising Result ◽  
Laboratory Studies ◽  
Data Support ◽  
Alternative Hypotheses ◽  
Insular Ecosystem

On a small island off south-western Australia, tiger snakes (Notechis scutatus, Elapidae) continue to survive, feed, grow and reproduce successfully after being blinded by seagulls defending their chicks. We propose two alternative hypotheses to explain this surprising result: either vision is of trivial importance in tiger snake foraging, or the blinded snakes survive on a diet of abundant immobile prey that cannot escape their approach. Laboratory studies in which we blindfolded snakes falsified the first hypothesis: snakes that were unable to see had great difficulty in capturing mobile prey. Field data support the second hypothesis: blind snakes feed almost entirely on seagull chicks, whereas normal-sighted animals also took fast-moving prey (lizards and mice). Thus, the ability of tiger snakes on Carnac Island to survive without vision is attributable to the availability of abundant helpless prey (seagull chicks) in this insular ecosystem.

scholarly journals Spectral form and source term balance of short gravity wind waves

2014 ◽  
Vol 70 (2) ◽  
pp. I_111-I_115
Author(s):  
Hitoshi TAMURA ◽  
William M. DRENNAN ◽  
Erik SAHLEE ◽  
Hans C. GRABER
Keyword(s):  
Source Term ◽  
Wind Waves ◽  
Spectral Form

Capillary–gravity and capillary waves generated in a wind wave tank: observations and theories

1995 ◽  
Vol 289 ◽  
pp. 51-82 ◽  
Author(s):  
Xin Zhang
Keyword(s):  
Power Law ◽  
Gravity Waves ◽  
Water Surface ◽  
Wind Wave ◽  
Wind Waves ◽  
Capillary Waves ◽  
Fourth Power ◽  
Two Dimensional ◽  
Short Waves ◽  
Surface Gradient

Short water surface waves generated by wind in a water tunnel have been measured by an optical technique that provides a synoptic picture of the water surface gradient over an area of water surface (Zhang & Cox 1994). These images of the surface gradient can be integrated to recover the shape of the water surface and find the two-dimensional wavenumber spectrum. Waveforms and two-dimensional structures of short wind waves have many interesting features: short and steep waves featuring sharp troughs and flat crests are very commonly seen and most of the short waves are far less steep than the limiting wave forms; waveforms that resemble capillary–gravity solitons are observed with a close match to the form theoretically predicted for potential flows (Longuet-Higgins 1989); capillaries are mainly found as parasitics on the downwind faces of gravity waves, and the longest wavelengths of those parasitic capillaries found are less than 1 cm; the phenomenon of capillary blockage (Phillips 1981) on dispersive freely travelling short waves is also observed. The spectra of short waves generated by low winds show a characteristic dip at the transition wavenumber between the gravity and capillary regimes, and the dip becomes filled in as the wind increases. The spectral cut-off at high wavenumbers shows a power law behaviour with an exponent of about minus four. The wavenumber of the transition from the dip to the cut-off is not sensitive to the change of wind speed. The minus fourth power law of the extreme capillary wind wave spectrum can be explained through a model of energy balances. The concept of an equilibrium spectrum is still useful. It is shown that the dip in the spectrum of capillary–gravity waves is a result of blockage of both capillary–gravity wind waves and parasitic capillary waves.

scholarly journals Higher spin wormholes from modular bootstrap

2021 ◽  
Vol 2021 (10) ◽  
Author(s):  
Diptarka Das ◽  
Shouvik Datta
Keyword(s):  
Form Factor ◽  
Partition Function ◽  
Power Law ◽  
Spectral Form ◽  
Ensemble Averaging ◽  
Level Statistics ◽  
Higher Spin ◽  
Random Matrix Ensembles ◽  
Matrix Ensembles ◽  
Euclidean Wormhole

Abstract We investigate the connection between spacetime wormholes and ensemble averaging in the context of higher spin AdS3/CFT2. Using techniques from modular bootstrap combined with some holographic inputs, we evaluate the partition function of a Euclidean wormhole in AdS3 higher spin gravity. The fixed spin sectors of the dual CFT2 exhibit features that starkly go beyond conventional random matrix ensembles: power-law ramps in the spectral form factor and potentials with a double-well/crest underlying the level statistics.

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