Solar flares and their effect on the Earth's magnetosphere as deduced from GPS network data

Possibilities of the navigation satellite GPS system for detecting solar flare effect on the Earth's ionosphere as well as geomagnetic disturbances in October-November 2003 caused by them are considered. As is shown signals of satellite navigation systems can be used both for registering the direct effect of solar flares and ionospheric storms originating at the same time and for detailed research into sudden ionospheric disturbances depending on Sun's zenith angle, ionizing radiation type and station geographical location.