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Showing 1 to 12 of 12 for “"Planetary Wave"”.
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Planetary Wave Activity Observed in Polar Mesospheric Clouds
… Cloud (PMC) dataset was investigated for planetary wave activity following the earlier study by <em>Merkel </em>[2002]. To counter the sparse nature of the data, four separate methods of analysis are used in determining if planetary waves are present and how they effect PMC formation. The …
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Role of Planetary Wave-Tide-Gravity Wave Interactions In Whole Atmosphere Coupling
… sites and compared to a co-located sodium lidar. Wave-wave interactions in the mesosphere and lower thermosphere (MLT) that may be responsible for the penetration of six-day periodicities into the Earth's ionosphere during the 2019 Southern Hemispheric (SH) SSW are first investigated. This study …
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Estimation of planetary wave parameters from the data of the 1981 ocean acoustic tomography experiment
… and minimization techniques, quasi-geostrophic wave solutions were fitted to the observations of the 1981 Ocean Acoustic Tomography Experiment. The experiment occupied a 300 km square area centered at 26°N, 70°W, and had a duration of ~80 days. The data set consisted of acoustic travel-time …
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The Steady-State Planetary Wave Response to Wave-Coupled Orographic Lower Boundary Forcing and Diabatic Heating in The Northern Hemisphere
A planetary wave model which is symmetric about the equator has been developed using the linear balance set of equations. The model is formulated on a sphere and spectrally truncated to 4 zonal and 7 meridional modes. There are 11 levels in the vertical with the highest computational level at 5 mb. …
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On the maintenance of weak meridional temperature gradients during warm climates
… maintain a weak temperature gradient. I examine planetary wave generation, the energetics of the general circulation, and vertical wave propagation in a general circulation model with a resolved stratosphere forced with a weak surface temperature gradient. Compared to the present climate, …
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The relationship between precipitation and electromagnetic signals in the Schumann resonances
… as well as the existence of an apparent planetary wave with approximate 5-day periodicity. Schumann resonance analyses have detected this wave in several regions of the world, suggesting that the physical origin of the wave is global. Regional analyses show a significant correlation …
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Analysis of Ionospheric Data Sets to Identify Periodic Signatures Matching Atmospheric Planetary Waves
Atmospheric planetary waves play a role in introducing variability to the low-latitude ionosphere. To better understand this coupling, this study investigates times when oscillations seen in both atmospheric planetary waves and ionospheric data-sets have similar periodicity. The planetary wave …
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A two-mode numerical model with applications to coastal upwelling
… with the South East Atlantic ocean; the planetary waves in the Agulhas return current over and east of the Agulhas plateau. Volume flux calculations (reference 1100m.) show that the two supplies to the Agulhas current could be estimated at 15 sverdrups each. The main part of the current …
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Middle latitude forcing of a model tropical atmosphere with horizontally nonuniform basic states
… state responses of the model atmosphere to planetary wave modes, each with a prescribed azimuthal wavenumber, meridional wavenumber, equivalent depth, and period at a middle latitude boundary are determined. The quasi-linear interactions between a forcing mode and the longitudinally varying …
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The role of wavenumber one and two in the development of sudden stratospheric warmings
In this thesis, we investigate the effects of planetary waves one and two on the polar stratosphere during boreal winter. We use MERRA reanalysis data and the FMS shallow-water model to compare and contrast their propagation into the stratosphere, their interactions within the stratosphere, and …
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A study on the sea level variations and the 'Milghuba' phenomenon in the coastal waters of the Maltese Islands
… the occurrence of mesoscale atmospheric gravity waves travelling in the lower troposphere. The associated open sea waves excite the water bodies of the various inlets, bays and harbours into resonant oscillations which reach a range of up to lmin Mellieha Bay. Numerical experiments based on the …
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Untersuchungen zur dynamischen Kopplung der Troposphäre und der Stratosphäre
Im Rahmen dieser Arbeit wurde ein besseres Verständnis der Kopplung der Troposphäre und der Stratosphäre in den mittleren und polaren Breiten der Nordhemisphäre (NH) auf Monatszeitskalen erzielt, die auf die Ausbreitung von quasi-stationären Wellen zurückzuführen ist. Der Schwerpunkt lag dabei auf …