A review of atmospheric gravity waves and travelling ionospheric disturbances: 1982-1995

Hocke, Klemens; Schlegel, K.

doi:10.1007/s00585-996-0917-6

Cited by 453 publications

(514 citation statements)

References 0 publications

Supporting

Mentioning

480

Contrasting

Unclassified

Order By: Relevance

“…These processes result in momentum and energy deposition in the thermosphere, which can result in a change in the background neutral wind and temperature (VF06; Becker and Fritts, 2006;Yigit et al, 2008Yigit et al, , 2009Fujiwara, 2008, 2009;Vadas andLiu, 2009, 2011;Yigit and Medvedev, 2010). Such GWs can also affect the ionosphere (e.g., Klostermeyer, 1972;Hocke and Schlegel, 1996;Hickey et al, 2009Hickey et al, , 2010.…”

Section: Liu Et Al: the Momentum Deposition Of Small Amplitude Grmentioning

confidence: 99%

Numerical modeling study of the momentum deposition of small amplitude gravity waves in the thermosphere

Liu

Yue

et al. 2013

Ann. Geophys.

View full text Add to dashboard Cite

Abstract. We study the momentum deposition in the thermosphere from the dissipation of small amplitude gravity waves (GWs) within a wave packet using a fully nonlinear two-dimensional compressible numerical model. The model solves the nonlinear propagation and dissipation of a GW packet from the stratosphere into the thermosphere with realistic molecular viscosity and thermal diffusivity for various Prandtl numbers. The numerical simulations are performed for GW packets with initial vertical wavelengths (λ z ) ranging from 5 to 50 km. We show that λ z decreases in time as a GW packet dissipates in the thermosphere, in agreement with the ray trace results of Vadas and Fritts (2005) (VF05). We also find good agreement for the peak height of the momentum flux (z diss ) between our simulations and VF05 for GWs with initial λ z ≤ 2πH in an isothermal, windless background, where H is the density scale height. We also confirm that z diss increases with increasing Prandtl number. We include eddy diffusion in the model, and find that the momentum deposition occurs at lower altitudes and has two separate peaks for GW packets with small initial λ z . We also simulate GW packets in a non-isothermal atmosphere. The net λ z profile is a competition between its decrease from viscosity and its increase from the increasing background temperature. We find that the wave packet disperses more in the non-isothermal atmosphere, and causes changes to the momentum flux and λ z spectra at both early and late times for GW packets with initial λ z ≥ 10 km. These effects are caused by the increase in T in the thermosphere, and the decrease in T near the mesopause.

show abstract

Section: Liu Et Al: the Momentum Deposition Of Small Amplitude Grmentioning

confidence: 99%

Numerical modeling study of the momentum deposition of small amplitude gravity waves in the thermosphere

Liu

Yue

et al. 2013

Ann. Geophys.

View full text Add to dashboard Cite

show abstract

“…This implies that the Corilolis force would be one of the main factors of controlling the propagation azimuths of LSTIDs during their propagation. The LSTIDs at high geomagnetic latitudes such as, the GPS array at geomagnetic latitude of 55.3 • N in North America and the GPS array at geomagnetic latitude of 52.6 • N in Europe, were near the auroral oval (source region), and were affected by the Coriolis force for a short time, so the southwestward deviations at these arrays were more likely to be related with the generation mechanisms such as the moving source (Hocke and Schlegel, 1996). However, it was obvious that the increased southwestward deviations of the LSTIDs during their propagation from high to middle geomagnetic latitudes were independent of the generation mechanisms which were more likely to be caused by the Coriolis force.…”

Section: Propagation Directions Of Lstidsmentioning

confidence: 99%

“…The LSTIDs have a horizontal scale of more than 1000 km and propagate equatorward at a velocity of 400∼1000 m s −1 (e.g. Hunsucker, 1982;Hocke and Schlegel, 1996).…”

Section: Introductionmentioning

confidence: 99%

Global propagation features of large-scale traveling ionospheric disturbances during the magnetic storm of 7~10 November 2004

et al. 2012

View full text Add to dashboard Cite

Abstract. Larger-scale traveling ionospheric disturbances (LSTIDs) were studied using the total electron content (TEC) data observed from global GPS network in the regions of North America, Europe, and East Asia during the magnetic storm of 7∼10 November 2004. 4 LSTID events were detected in North America, 4 in Europe, and 3 in East Asia. The parameters of the 11 LSTID events, such as the propagation azimuth (the angle with respect to north, taking clockwise as positive), horizontal phase velocity and damping rate were determined. Our results showed two new propagation features of the LSTIDs. One was the latitudinal dependence of the LSTIDs' propagation azimuths. The LSTIDs tended to deflect more to west from south as they propagated to lower latitudes, which indicated that the Coriolis force was one of the main causes of the LSTIDs' southwestward deviation. The other was the different mean horizontal phase velocities of LSTIDs among different regions. The mean horizontal phase velocity of LSTIDs was 422 ± 36 m s −1 in North America, 381 ± 69 m s −1 in Europe, and 527 ± 21 m s −1 in East Asia, respectively. The results also indicated that the amplitudes of LSTIDs decreased during their propagation for every event, and the daytime damping rates were more than 1 time larger than the nighttime ones due to different ion drag between daytime and nighttime. The source regions of the LSTIDs were likely to be located between geomagnetic latitudes of 68 • N and 62 • N in North America, and between 65 • N and 57 • N in Europe, according to the variation of magnetic H component observed in these two regions.

show abstract

“…Properties of the traveling ionospheric disturbances (TIDs) have been investigated extensively recently by means of observations and numerical simulation (as reviewed by Hocke and Schlegel, 1996, and references therein). It is now widely accepted that TIDs are the ionospheric manifestations of atmospheric gravity waves (AGW) since the landmark paper of Hines (1960).…”

Section: Introductionmentioning

confidence: 99%

Simultaneous observations of large-scale traveling ionospheric disturbances on the nightside and dayside middle latitude

Cai

Yin

et al. 2012

Ann. Geophys.

View full text Add to dashboard Cite

Abstract. In this paper, we present further observational evidence for the transpolar propagation of large-scale traveling ionospheric disturbances (LSTIDs) from their nightside source region to the dayside reported by Cai et al. (2011). Slant total electron content (STEC) observed by longitudinally aligned GPS receiver chains in North American and European sectors was analyzed to demonstrate presences of LSTIDs at both nightside and dayside mid-latitude. Signatures of TID were inferred from phase difference in time series of STEC perturbations (TECP) derived from measurements of ground-based GPS receivers, which are separated by hundreds of kilometers longitudinally. Periods of the daytime and nighttime ionospheric disturbances were estimated to be around 128 min, being in good agreement with that of the transpolar AGW (atmospheric gravity wave) recorded by EISCAT (European Incoherent Scatter Scientific Association)/ESR (EISCAT Svalbard Radar) radars. On the dayside, the LSTID moved equatorward with an average phase speed of ∼440 m s −1 . In North American sector, however, southward speed of the nighttime LSTID was much slower, being around 160 m s −1 . We suggest that the observed daytime and nighttime mid-latitude LSTIDs are likely to have the same source region, being located somewhere at nighttime auroral latitude. Having been launched on the nightside, the waves propagate simultaneously equatorward and poleward. The equatorward-moving waves are recorded by GPS receiver chain in North American sector. The polewardmoving waves, however, cross the polar cap from nightside to dayside and then are detected consecutively at high and midlatitudes by EISCAT/ESR radars and GPS receiver chains, respectively.

show abstract

A review of atmospheric gravity waves and travelling ionospheric disturbances: 1982-1995

Cited by 453 publications

References 0 publications

Numerical modeling study of the momentum deposition of small amplitude gravity waves in the thermosphere

Numerical modeling study of the momentum deposition of small amplitude gravity waves in the thermosphere

Global propagation features of large-scale traveling ionospheric disturbances during the magnetic storm of 7~10 November 2004

Simultaneous observations of large-scale traveling ionospheric disturbances on the nightside and dayside middle latitude

Contact Info

Product

Resources

About