Global Ionospheric Maps
Data from over 100+ continuously operating GPS receivers in a global network are being used to produce global maps of the ionosphere's total electron content (TEC). These Global Ionosphere Maps (GIM) provide instantaneous "snapshots" of the global TEC distribution, by interpolating, in both space and time, the 6-8 simultaneous TEC measurements obtained from each GPS receiver every 30 seconds. The maps can be produced unattended in a real-time mode, with an update rate of 5-15 minutes.
Monitoring Global Ionospheric Weather
GIMs represent a new tool for monitoring global patterns of ionospheric weather, a key component of the space weather, which is driven by changes in solar ultra-violet radiation, the interplanetary particle stream known as the solar wind, and the underlying composition, wind patterns and electrodynamics of the thermosphere (the upper atmosphere at altitudes between 100 and 1000 km). GIMs are being used for global ionospheric delay calibrations, for scientific investigations of the upper atmosphere, and will be an important data source for the National Space Weather Program.