I^^K^ • We analyzed ionospheric observations made with digisondes in Jicamarca, Ramey, Wallops Island, Ascension Island, and Kwajalein Island during the major magnetic storm of November 9-10, 2004 that was associated with rapid interplanetary magnetic field (IMF) Bz changes. The strongest ionospheric responses to the southward IMF Bz turning were observed at the dip equator at Jicamarca where d...

Ionospheric slab thickness is defined as the ratio of TEC to maximum electron density of the F-region (NmF2), proportional to the square of the F2-layer critical frequency (foF2). It is an important parameter in that it is linearly correlated with scale height of the ionosphere, which is related to electron density profile. It also reflects variation of the neutral temperature. Therefore, ionos...

[1] We use the Global Ionosphere-Thermosphere Model (GITM) to simulate the ionospheric reaction to a simple step change of the high-latitude forcing terms during the first hour of electric field enhancement. In response to the enhanced convection electric field, both the convection velocity and Joule heating increase dramatically. The changes in NmF2 present that the tongue extends across the p...

For a long time, the equivalent ionospheric slab thickness ? has remained in shadow of main parameters: maximum density, NmF2 (or critical frequency, foF2), and total electron content. Empirical global models have been developed for these two parameters. Recently, several appeared concurrently. This paper compares Neustrelitz model (NSTM), with ?(IRI-Plas) IRI-Plas model, ?(Appr) approximation ...

A new theoretical model of the Earth’s lowand mid-latitude ionosphere and plasmasphere has been developed. The new model uses a new method in ionospheric and plasmaspheric simulations which is a combination of the Eulerian and Lagrangian approaches in model simulations. The electron and ion continuity and energy equations are solved in a Lagrangian frame of reference which moves with an individ...

We examine impacts of geomagnetic activity (GA) on CO2-driven trend in the ionosphere and thermosphere using Ground-to-topside Atmosphere Ionosphere model for Aeronomy whole atmosphere model. The reveals three salient features. (1) Geomagnetic activities usually weakens at a fixed altitude. Among IT parameters analyzed, mass density is most robust indicator CO2 cooling effect even with GA influ...

[1] The global ionospheric map (GIM) is used to observe variations in the total electron content (TEC) of the global positioning system (GPS) associated with 35 M 6.0 earthquakes that occurred in China during the 10-year period of 1 May 1998 to 30 April 2008. The statistical result indicates that the GPS TEC above the epicenter often pronouncedly decreases on day 3–5 before 17 M 6.3 earthquakes...