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Current global TEC

USU GAIM_GM Realtime Global

Real-time global GAIM ionosphere data started on September 1, 2009. SWC began operations of the global Gauss-Markov GAIM system on its servers. Real-time ionosphere data of total electron content (TEC) and time-dependent electron density profiles are generated every 15 minutes.  

The motivation for developing GAIM is because government and commercial users have a critical need for reliable high-frequency (HF) communications and for accuracy knowledge in GPS-based navigation systems. To satisfy this need requires an accurate specification of the effect that the upper atmosphere/ionosphere has on operational communication links and navigation systems. Like the Earth’s lower atmosphere, the Earth’s upper atmosphere and ionosphere (ionized gas) display highly variable and turbulent densities, temperatures, and winds, and these features are manifestations of space weather. These disturbances can adversely affect systems and operations, including over-the-horizon radars, HF communications, Global Position System (GPS) navigation, and GPS aided geo-location. Ionospheric corrections are particularly important for accurate location knowledge and for obtaining usable communication frequencies between two geographic locations.

The Utah State University team at the Space Weather Center has developed a data assimilation model of the Earth’s upper atmosphere/ionosphere that is similar to the tropospheric weather models run by NOAA. This space weather model, which is called the Global Assimilation of Ionospheric Measurements (GAIM), provides real-time specifications and forecasts for global distributions of upper atmosphere/ionosphere densities, temperatures, and winds. The GAIM space weather model originally became an operational Air Force model at the AFWA in December 2006.

The commercially operational GAIM Gauss-Markov global ionosphere data began with 357 TEC stations (the IGS network) with up to 10,000 measurements ingested every 15 minutes. The real-time data is assimilated into the Ionosphere Forecast Model (IFM), a background physics-based ionosphere.