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Oceanography and Atmospheric Sciences and Meteorology Commons™
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- Acoustic-gravity waves (2)
- Gravity wave (2)
- Incoherent scatter radar (2)
- Auroral electric fields (1)
- Beam‐plasma instability (1)
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- Convection (1)
- Diagnostics (1)
- Energy flux (1)
- Group velocity (1)
- Instruments and techniques (1)
- Ionosphere (1)
- Ionosphere/atmosphere interactions (1)
- Ionospheric composition (1)
- Ionospheric disturbances (1)
- Langmuir decay (1)
- Langmuir harmonics (1)
- NEIAL (1)
- Ocean/atmosphere interactions (1)
- Particle‐in‐cell simulation (1)
- Snowfall (1)
- TEC (1)
- TID (1)
- Thermosphere (1)
- Thermosphere: energy deposition (1)
- Thunderstorms (1)
- Total electron content (1)
- Tsunami (1)
- Tsunamis and storm surges (1)
- Wave dissipation (1)
- Winter/cool season (1)
Articles 1 - 6 of 6
Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology
Gravity Wave Heating And Cooling Of The Thermosphere: Sensible Heat Flux And Viscous Flux Of Kinetic Energy, Michael P. Hickey Ph.D., R. L. Walterscheid, G. Schubert
Gravity Wave Heating And Cooling Of The Thermosphere: Sensible Heat Flux And Viscous Flux Of Kinetic Energy, Michael P. Hickey Ph.D., R. L. Walterscheid, G. Schubert
Publications
Total wave heating is the sum of the convergence of the sensible heat flux and the divergence of the viscous flux of wave kinetic energy. Numerical simulations, using a full-wave model of the viscous damping of atmospheric gravity waves propagating in a nonisothermal atmosphere, are carried out to explore the relative contributions of these sources of wave heating as a function of wave properties and altitude. It is shown that the sensible heat flux always dominates in the lower thermosphere, giving a lower region of heating and an upper stronger region of cooling. The heating due to the divergence of …
Particle‐In‐Cell Simulation Of Incoherent Scatter Radar Spectral Distortions Related To Beam‐Plasma Interactions In The Auroral Ionosphere, M. A. Diaz, M. Oppenheim, J. L. Semeter, M. Zettergren
Particle‐In‐Cell Simulation Of Incoherent Scatter Radar Spectral Distortions Related To Beam‐Plasma Interactions In The Auroral Ionosphere, M. A. Diaz, M. Oppenheim, J. L. Semeter, M. Zettergren
Publications
An electrostatic parallel particle‐in‐cell (EPPIC) code that allows for particle beam injections and multiple boundary conditions is used to investigate the beam‐plasma interaction and its manifestations in the incoherent scatter (IS) spectrum. Specifically, the code is used to investigate anomalous enhancements in the ion acoustic line through the destabilization of the plasma by injection (or precipitation) of low‐energy electron beams. This enhancement of the ion acoustic line is a form of IS distortion commonly observed in the vicinity of auroral arcs called the naturally enhanced ion‐acoustic line (NEIAL). Simulations confirm the parametric decay of Langmuir waves as a plausible mechanism, …
The 2009 Samoa And 2010 Chile Tsunamis As Observed In The Ionosphere Using Gps Total Electron Content, David A. Galvan, Attila Komjathy, Michael P. Hickey Ph.D., Anthony J. Mannucci
The 2009 Samoa And 2010 Chile Tsunamis As Observed In The Ionosphere Using Gps Total Electron Content, David A. Galvan, Attila Komjathy, Michael P. Hickey Ph.D., Anthony J. Mannucci
Publications
Ground‐based Global Positioning System (GPS) measurements of ionospheric total electron content (TEC) show variations consistent with atmospheric internal gravity waves caused by ocean tsunamis following two recent seismic events: the Samoa earthquake of 29 September 2009 and the Chile earthquake of 27 February 2010. Both earthquakes produced ocean tsunamis that were destructive to coastal communities near the epicenters, and both were observed in tidal gauge and buoy measurements throughout the Pacific Ocean. We observe fluctuations in TEC correlated in time, space, and wave properties with these tsunamis using the Jet Propulsion Laboratory’s Global Ionospheric Mapping software. These TEC measurements were …
Group Velocity And Energy Flux In The Thermosphere: Limits On The Validity Of Group Velocity In A Viscous Atmosphere, R. L. Walterscheid, Michael P. Hickey Ph.D.
Group Velocity And Energy Flux In The Thermosphere: Limits On The Validity Of Group Velocity In A Viscous Atmosphere, R. L. Walterscheid, Michael P. Hickey Ph.D.
Publications
The response to wave forcing of finite duration comprises a transient forerunner and the steady state signal (or simply the signal). It is the latter that carries information on the spectral content of the forcing, and the signal velocity is the velocity at which wave energy flows. To the extent that group velocity is a good measure of the energy flow velocity, the ray‐tracing formalism is a valid description of signal propagation. We have examined vertical group velocities as a measure of vertical energy flow velocity for gravity and acoustic waves propagating into the dissipative lower thermosphere. We find that …
A Diagnostic Examination Of The Eastern Ontario And Western Quebec Wintertime Convection Event Of 28 January 2010, Shawn M. Milrad, John R. Gyakum, Eyad H. Atallah, Jennifer F. Smith
A Diagnostic Examination Of The Eastern Ontario And Western Quebec Wintertime Convection Event Of 28 January 2010, Shawn M. Milrad, John R. Gyakum, Eyad H. Atallah, Jennifer F. Smith
Publications
The priority of an operational forecast center is to issue watches, warnings, and advisories to notify the public about the inherent risks and dangers of a particular event. Occasionally, events occur that do not meet advisory or warning criteria, but still have a substantial impact on human life and property. Short-lived snow bursts are a prime example of such a phenomenon. While these events are typically characterized by small snow accumulations, they often cause very low visibilities and rapidly deteriorating road conditions, both of which are a major hazard to motorists. On the afternoon of 28 January 2010, two such …
Incoherent Scatter Radar Estimation Of F Region Ionospheric Composition During Frictional Heating Events, M. Zettergren, J. L. Semeter, C. Heinselman, M. Diaz
Incoherent Scatter Radar Estimation Of F Region Ionospheric Composition During Frictional Heating Events, M. Zettergren, J. L. Semeter, C. Heinselman, M. Diaz
Publications
A method is developed for estimating F region ion composition from incoherent scatter radar (ISR) measurements during times of frictional ion heating. The technique addresses ion temperature‐mass ambiguities in the IS spectra by self‐consistently modeling ion temperature profiles, including the effects of ion temperature anisotropies and altitude‐independent neutral winds. The modeled temperature profiles are used in a minimization procedure to estimate ion composition consistent with the recorded IS spectra. The proposed method is applicable to short‐integration (min) data sets from either single‐beam or multiple‐beam experiments. Application of the technique to Sondrestrom ISR measurements shows increases in F region molecular ions …