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Full-Text Articles in Physical Sciences and Mathematics
Ionospheric Gravity Waves Driven By Oceanic Gravity Waves In Resonance: A Modeling Study In Search Of Their Spectra, Michael P. Hickey, Yonghui Yu
Ionospheric Gravity Waves Driven By Oceanic Gravity Waves In Resonance: A Modeling Study In Search Of Their Spectra, Michael P. Hickey, Yonghui Yu
Publications
Ionospheric observations associated with the 2011 Tohoku tsunami have revealed gravity waves having spectral characteristics that depend on their proximity to the epicenter. There is a preponderance of medium-scale waves in the vicinity of the epicenter, a significant bifurcation into short- and long-period waves over the Hawaiian archipelago, and a narrow and rich spectrum of waves over the West Coast and inland of the United States (U.S.). Guided by these previous observations, we consider wave sources as triads of nonlinearly interacting oceanic gravity waves, whose wave parameters satisfy resonant conditions. These waves are simulated using a 2-D nonlinear model describing …
Ionospheric Signatures Of Gravity Waves Produced By The 2004 Sumatra And 2011 Tohoku Tsunamis: A Modeling Study, Michael P. Hickey, Yonghui Yu, Wenqing Wang
Ionospheric Signatures Of Gravity Waves Produced By The 2004 Sumatra And 2011 Tohoku Tsunamis: A Modeling Study, Michael P. Hickey, Yonghui Yu, Wenqing Wang
Publications
Ionospheric fluctuations inferred from observations of total electron content have previously been attributed to tsunamis and have confirmed the strong coupling between Earth’s ocean and ionosphere via atmospheric gravity waves (AGWs). To further advance our understanding of this wave coupling process we employ a linear full-wave model and a nonlinear time-dependent model to examine the ionospheric response to the AGW perturbations induced by the 2004 Sumatra and the 2011 Tohoku tsunamis. In the 2004 case, our modeling analyses reveal that one component of the propagating AGWs becomes dynamically unstable in the E-region ionosphere at a range exceeding 2000 km in …
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 …
Atmospheric Airglow Fluctuations Due To A Tsunami‐Driven Gravity Wave Disturbance, Michael P. Hickey Ph.D., G. Schubert, R. L. Walterscheid
Atmospheric Airglow Fluctuations Due To A Tsunami‐Driven Gravity Wave Disturbance, Michael P. Hickey Ph.D., G. Schubert, R. L. Walterscheid
Publications
A spectral full‐wave model is used to study the upward propagation of a gravity wave disturbance and its effect on atmospheric nightglow emissions. Gravity waves are generated by a surface displacement that mimics a tsunami having a maximum amplitude of 0.5 m, a characteristic horizontal wavelength of 400 km, and a horizontal phase speed of 200 m/s. The gravity wave disturbance can reach F region altitudes before significant viscous dissipation occurs. The response of the OH Meinel nightglow in the mesopause region (∼87 km altitude) produces relative brightness fluctuations, which are ∼1% of the mean for overhead viewing. The wave …
Propagation Of Tsunami-Driven Gravity Waves Into The Thermosphere And Ionosphere, Michael P. Hickey, G. Schubert, R. L. Walterscheid
Propagation Of Tsunami-Driven Gravity Waves Into The Thermosphere And Ionosphere, Michael P. Hickey, G. Schubert, R. L. Walterscheid
Publications
Recent observations have revealed large F-region electron density perturbations (~100%) and total electron content (TEC) perturbations (~30%) that appear to be correlated with tsunamis. The characteristic speed and horizontal wavelength of the disturbances are ~200 m/s and ~400 km. We describe numerical simulations using our spectral full-wave model (SFWM) of the upward propagation of a spectrum of gravity waves forced by a tsunami, and the interaction of these waves with the F-region ionosphere. The SFWM describes the propagation of linear, steady-state acoustic-gravity waves in a nonisothermal atmosphere with the inclusion of eddy and molecular diffusion of heat and momentum, ion …