The sources of atmospheric gravity waves

Nagpal, O. P.

doi:10.1080/00107517908210928

Cited by 12 publications

(10 citation statements)

References 42 publications

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“…IGWs are generated by flows surging up mountains (Gossard and Hook, 1975;Lindzen, 1984), atmospheric fronts and jet streams (Ley and Peltier, 1982;Nagpal, 1979;Barat, 1984;Lindzen, 1984), convective layers (Townsend, 1966), cumulus clouds and thunderstorms (Grachev et al, 1984;Taylor and Hapgood, 1988;Kazimirovski, 1983), volcanoes (Roberts et al, 1982), typhoons (Hung et al, 1985), oscillations of sea surface (Golitcin et al, 1976), by earthquakes (Kolcov et al, 1986;Samardziev and Pashova, 1982), ground level explosions (Hunt et al, 1960;Abramov et al, 1984;Harkrider, 1964), shear flows (Townsend, 1968;Lindzen, 1984), moving things (Grigoriev and Savina, 1983) burning down satellites (Kulikov et al, 1982), big fires, etc.…”

Section: Introductionmentioning

confidence: 99%

Vertical propagation, breaking and effects of nonlinear gravity waves in the atmosphere

Кшевецкий

Гаврилов²

2005

Journal of Atmospheric and Solar-Terrestrial Physics

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Section: Introductionmentioning

confidence: 99%

Vertical propagation, breaking and effects of nonlinear gravity waves in the atmosphere

Кшевецкий

Гаврилов²

2005

Journal of Atmospheric and Solar-Terrestrial Physics

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“…The small-scale GW with wavelengths of a few kilometers and periods near 10 min are generated in the planetary boundary layer (Nagpal 1979). The medium-scale GW with horizontal wavelengths of about 100-1,000 km, vertical wavelengths of 1-10 km, and periods of 10 min to 1 h, are mainly produced owing to the weather activities (fronts, cyclones, cumulonimbus convection, thunderstorms) and wind flows over irregular topography (mountain waves).…”

Section: Introductionmentioning

confidence: 99%

“…The gravity waves (GW) in the atmosphere have been observed and modeled for many years (Nagpal 1979). The small-scale GW with wavelengths of a few kilometers and periods near 10 min are generated in the planetary boundary layer (Nagpal 1979).…”

Section: Introductionmentioning

confidence: 99%

Response of GPS occultation signals to atmospheric gravity waves and retrieval of gravity wave parameters

et al. 2004

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We show that the amplitude of the Global Positioning System (GPS) signals in the radio occultation (RO) experiments is an indicator of the activity of the gravity waves (GW) in the atmosphere. The amplitude of the GPS RO signals is more sensitive to the atmospheric wave structures than is the phase. Early investigations used only the phase of the GPS occultation signals for statistical investigation of the GW activity in the height interval 10-40 km on a global scale. In this study, we use the polarization equations and Hilbert transform to find the 1-D GW radio image in the atmosphere by analyzing the amplitude of the RO signal. The radio image, also called the GW portrait, consists of the phase and amplitude of the GW as functions of height. We demonstrate the potential of this method using the amplitude data from GPS/Meteorology (GPS/MET) and satellite mission Challenge Minisatellite Payload (CHAMP) RO events. The GW activity is nonuniformly distributed with the main contribution associated with the tropopause and the secondary maximums related to the GW breaking regions. Using our method we find the vertical profiles of the horizontal wind perturbations and its vertical gradient associated with the GW influence. The estimated values of the horizontal wind perturbations are in fairly good agreement with radiosonde data. The horizontal wind perturbations v(h) are ±1 to ±5 m s with vertical gradients dv/dh ±0.5 to ±15 m s km at height 10-40 km. The height dependence of the GW vertical wavelength was inferred through the differentiation of the GW phase. Analysis of this dependence using the dispersion relationship for the GW gives the estimation of the projection of the horizontal background wind velocity on the direction of the GW propagation. For the event considered, the magnitude of this projection changes between 1.5 and 10 m s at heights of 10-40 km. We conclude that the amplitude of the GPS occultation signals contain important information about the wave processes in the atmosphere on a global scale.

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“…The gravity waves (GW) in the atmosphere have been observed and modeled for many years (Nagpal, 1979). The GW with horizontal wavelengths $100-1000 km, vertical wavelengths $1-10 km, and periods $10 min-1 h are mainly produced owing to the weather activities (fronts, cyclones, cumulonimbus convection, thunderstorms) and wind flows over irregular topography (mountain waves), and play a decisive role in transporting energy and momentum, in contributing turbulence and mixing, and in affecting the atmospheric circulation and temperature regime (Fritts and Alexander, 2003).…”

Section: Introductionmentioning

confidence: 99%