This paper presents data from low-elevation satellites on 20 November 2003 in the Ohio region, the area of the largest validated gradients seen to date. As viewed by multiple CORS stations in central and northeastern Ohio, SVN 26 came into view around 2030 UT on this day, rose to an elevation angle of about 15 degrees just after 2100 UT, and set between 2135 and 2200 UT. This observation window...

This work addresses some of the key topics of space physics research recommended in the National Research Council 2003 report “A Decadal Research Strategy in Solar and Space Physics”, namely, the thunderstorm-driven electrodynamic coupling between the troposphere, mesosphere, lower ionosphere, and magnetosphere. Lightning-induced electron precipitation encompasses all of these regions, from atm...

Waves identified as whistler-mode waves have been observed in the nightside ionosphere of Venus by the Pioneer Venus Orbiter. These waves are propagating in a collisional, weakly magnetized ionosphere, and it has been argued that as such they should be damped through collisions, and the wave should not retain the characteristics of the whistler-mode because of non-linear modifications to the di...

Intense HF radiation from a ground-based facility heats the D-region of the ionosphere. The heating modifies the electron energy distribution function, which is found by solving the kinetic equation at each spatial location. The solution selfconsistently takes into account attenuation of HF radiation due to modified HF conductivity. A modulation HF radiation at ELF/VLF frequencies creates corre...

This paper evaluates the real-time positioning performance of a single-frequency receiver using the 1Hz differential corrections as provided by NASA’s Global Differential GPS (GDGPS) System. While a dualfrequency user has the ability to eliminate the ionosphere error by taking a linear combination of observables, a single-frequency user must remove or calibrate this error by other means. To rem...

[1] We analyze 2 years of the FORMOSAT-3/COSMIC GPS radio occultation data to study the response of the Earth’s ionosphere to the solar rotation (27-day) induced solar flux variations. Here we report electron density variations in the ionosphere ( 100–500 km) associated with the 27-day solar cycle. The peak-to-peak variation in electron density at low latitudes in the F2 region is about 10–10 e...

[1] The long-duration positive ionospheric storm effect that occurred on 15 December 2006 is investigated using a combination of ground-based Global Positioning System (GPS) total electron content (TEC), TOPEX and Jason-1 TEC, and topside ionosphere/ plasmasphere TEC, GPS radio occultation, and tiny ionospheric photometer (TIP) observations from the Constellation Observing System for Meteorolog...

The 1957-58 International Geophysical Year (IGY) is regarded by many as the threshold of mankind’s entry into space exploration. Now 58 years later, we understand and can describe in detail the five complete solar cycles since then, and the differences between them. We know that the Earth’s magnetic field has changed, causing changes in our planet’s space weather shield. The Earth’s atmosphere ...

[1] Beside the GPS radio occultation measurements of the troposphere and ionosphere, the CHAMP satellite tracks presently up to 8 GPS satellites simultaneously for navigation. The received dual frequency GPS signals provide valuable information on the ionization state of the topside ionosphere and plasmasphere. This paper briefly describes a new developed model assisted technique to improve the...