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Collisional shear instability in the equatorial F region ionosphere
(American Geophysical Union, 2004-11-03)
A collisional shear instability in a magnetized plasma is described and evaluated. The instability is related to electrostatic Kelvin Helmholtz but operates in inhomogeneous plasmas in the collisional regime. Boundary value ...
The equatorial E-region and its plasma instabilities: a tutorial
(European Geosciences Union, 2009-04-02)
In this short tutorial we first briefly review the basic physics of the E-region of the equatorial ionosphere, with emphasis on the strong electrojet current system that drives plasma instabilities and generates strong ...
Possible ionospheric preconditioning by shear flow leading to equatorial spread F
(European Geosciences Union (EGU), 2005-10-14)
Vertical shear in the zonal plasma drift speed is apparent in incoherent and coherent scatter radar observations of the bottomside F region ionosphere made at Jicamarca from about 1600–2200 LT. The relative importance of ...
Bottom-type scattering layers and equatorial spread F
(European Geosciences Union (EGU), 2004-12)
Jicamarca radar observations of bottom-type coherent scattering layers in the post-sunset bottomside F-region ionosphere are presented and analyzed. The morphology of the primary waves seen in radar images of the layers ...
Equatorial spread-F initiation: Post-sunset vortex, thermospheric winds, gravity waves
(Elsevier, 2007-12)
We present experimental evidence and modeling results which indicate that eastward thermospheric wind is the primary controlling factor of equatorial spread-F initiation in the post-sunset ionosphere. Eastward wind-driven ...
On the plasma instability mechanisms responsible for Esq
(American Geophysical Union, 1976-03-01)
Evidence is presented showing that the gradient drift (type 2) irregularities are the most probable scatterers responsible for equatorial sporadic E (Esq) echoes observed on conventional equatorial ionograms and that the ...
Ion thermal effects on E-region instabilities: linear theory
(Elsevier, 2004-11)
Linear instabilities and turbulent processes in ionospheric electrojets lead to the formation of plasma density irregularities which create strong radar reflections. Studies of these irregularities have focused on the role ...
Imaging radar observations and nonlocal theory of large-scale plasma waves in the equatorial electrojet
(European Geosciences Union (EGU), 2002)
Large-scale (λ∼1 km) waves in the daytime and nighttime equatorial electrojet are studied using coherent scatter radar data from Jicamarca. Images of plasma irregularities within the main beam of the radar are formed using ...
Assimilative modeling of the equatorial ionosphere for scintillation forecasting: modeling with vertical drifts
(American Geophysical Union, 2005-11-19)
Knowledge of the vertical plasma drift velocity observed by the Jicamarca incoherent radar in seven events is assimilated into a theoretical model for the ambient F region plasma density. Comparisons of the calculated ...
Modeling the low-latitude ionospheric electron density and plasma turbulence in the November 2004 storm period
(Elsevier, 2010-03)
The storm period of 8–12 November 2004 offers an opportunity for insight into the phenomena of low-latitude ionospheric structure during geomagnetically disturbed times because of the strength of the disturbances, the ...