[1] Modulated high frequency (HF, 3–10 MHz) heating of the ionosphere in the presence of the auroral electrojet currents is an effective method for generating extremely low frequency (ELF, 3–3000 Hz) and very low frequency (VLF, 3–30 kHz) radio waves. The amplitudes of ELF/VLF waves generated in this manner depend sensitively on the auroral electrojet current strength, which varies with time. I...

Combining analyses of spatial and temporal characteristics of the ionosphere is of great significance for scientific research and engineering applications. Tensor decomposition is performed to explore the temporal–longitudinal– latitudinal characteristics in the ionosphere. Three-dimensional tensors are established based on the time series of ionospheric vertical total electron content maps obt...

[1] This article reports the first high time resolution measurements of gigantic jets from the Imager of Sprites and Upper Atmospheric Lightning (ISUAL) experiment. The velocity of the upward propagating fully developed jet stage of the gigantic jets was 10 m s , which is similar to that observed for downward sprite streamers. Analysis of spectral ratios for the fully developed jet emissions gi...

The time evolution of field-aligned current-generated transient features in the high-latitude ionosphere is investigated. Ionospheric return currents generate signdicant downward heavy ion flows in the topside ionosphere with peak values well exceeding 10 scm'2s 'i. When the return current ceases the polar ionosphere rapidly returns to its previous equilibrium state. During the recovery phase o...

The distribution of electrons in the ionosphere is of interest to scientists and also to engineers working on applications such as earth–space communication systems, which must transmit through the ionosphere, and skywave systems, which make use of ionospheric refraction. Electron content is commonly examined using total electron content (TEC) mapping. This mapping finds use in other applicatio...

The ionosphere is the major contributor of errors in Global Positioning System (GPS), especially during the 11-year sunspot cycle. The incoming 11-year sunspot cycle is expected to peak in 2013. The ionosphere condition is distinctly severe during ionospheric disturbances caused by high solar activity, which raises the question of how will this affect the ionosphere in the equatorial region, es...

Atmospheric electricity has been detected in all gaseous giants of our solar system and is therefore likely present also in extrasolar planets. Building upon measurements from Saturn and Jupiter, we investigate how the electromagnetic pulse emitted by a lightning stroke affects upper layers of a gaseous giant. This effect is probably significantly stronger than that on Earth. We find that elect...

The radio holography methodology may be applied in the scientific programs for future small satellite that will use radio signals emitted by radio navigation, radio communication satellites for precise measuring effects of radio waves propagation at low elevation angles and for global monitoring of radio communication channels passed through the atmosphere and ionosphere. Another task consists ...

Extremely large ionospheric gradients can pose a potential integrity threat to the users of Local Area Augmentation System (LAAS), and thus the development of an ionospheric anomaly threat model is essential for system design and operation. This paper presents a methodology for long-term ionosphere monitoring which will be used to build an ionosphere threat model, evaluate its validity over the...

The advent of a second civil GPS frequency heralds a new phase of GPS performance. For single-frequency GPS users, the signal delay due to refraction through the ionosphere is the largest and most variable source of positioning error. Dual-frequency users take advantage of the dispersive nature of the ionosphere, combining the GPS observables to eliminate most of this error, on the order of met...