HIGH-RESOLUTION TEC MONITORING METHOD USING PERMANENT GROUND GPS RECEIVERS

In this paper we propose a new and simple method for obtaining the ion ospheric Total. Electron Content (TEC) variations from GPS permanent s tation data, in avery precise manner and with high temporal and spatia l resolution. The key idea is to use of the resonant period of 1 sider eal day between the Earth's rotation and the GPS satellite orbit perio ds, in order to obtain one TEC variation estimate directly from each i onospheric observation. This new strategy can be applied on both globa l and local scales, for instance to one single station. Its capabiliti es are shown in the application performed with the data gathered on 17 , 18 and 19 October 1995 from 95 GPS permanent stations and 9 and 10 J anuary 1997 (180 stations), coinciding with two major geomagnetic stor ms.