Ocean tsunami wavelengths are sufficiently long to produce atmospheric internal gravity waves that propagate to the ionosphere, creating disturbances in ionospheric electron density that travel with the ocean waves below. These traveling ionospheric disturbances (TIDs) can be observed using measurements of integrated ionospheric electron density (also known as total electron content, or TEC) be...

Space based GPS measurements onboard Low Earth Orbiting (LEO) satellites provide a uniquepossibility for exploring the ionosphere on a global scale. Both the radio occultation measurements in thelimb sounding mode and the navigation measurements using a zenith viewing GPS antenna provide theTotal Electron Content (TEC) along numerous ray paths. TEC may effectively be used for re...

The International Reference Ionosphere model 2001 (IRI-2001) is one of the most comprehensive empirical models of the ionosphere and has been widely used to estimate the electron density profiles in the altitude ranging from about 60 to 2000 km and the total electron content (TEC) at any given location, time and date, which reflect smooth-average global ionospheric behaviors. However, whether i...

The ionosphere is about 60-1000 km above the earth’s surface, which is actually plasma of ionized gas of the upper atmosphere by solar radiation and high-energy particles from the Sun. The ionized electrons concentrations change with height above earth’s surface, location, time of the day, season, and amount of solar activity. The total electron content (TEC) and electron density profiles are t...

The GPS Real-Time Ionospheric Monitoring System (GRIMS) has been operational at the Millstone Hill radar in Massachusetts since 1991 and at the FPS-85 radar in Florida since 1994. GRIMS employs GPS derived estimates of the total electron content (TEC) to provide real-time ionospheric corrections to radar measurements, incorporating data from a single receiver to generate TEC estimates for the e...

Successful empirical modeling of the topside ionosphere relies on the availability of good quality measured data. The Alouette, ISIS and Intercosmos-19 satellite missions provided large amounts of topside sounder data, but with limited coverage of relevant geophysical conditions (e.g., geographic location, diurnal, seasonal and solar activity) by each individual mission. Recently, methods for i...

[1] The relationship between total electron content (TEC) and the solar soft X-ray irradiances is presented. Three bands (2–7 nm, 6–19 nm, and 17–20 nm) of solar soft X-ray measurements from the Student Nitric Oxide Explorer (SNOE) satellite are examined and all show a similar relationship with TEC. The TEC data are from a GPS receiver near Ancon, Peru ( 11.78 degrees latitude, 77.15 degrees lo...