Ionospheric data monitoring and managing system and improvement of total electron content and ionospheric scintillation over the brazilian territory

Abstract

Earth's ionosphere in the tropical region (Brazil) had not a well behavior as a medium latitudes. It shows latitudinal gradients of electronic density and Total Electron Content (TEC) due the the Equatorial Ionospheric Anomaly (EIA) presence and the ionospheric plasma irregularities (bubbles). TEC causes a delay in the magnetic signal that crosses the ionosphere. Ionospheric irregularities are generated after the sunset in the magnetic Equator due the plasma instabilities (Rayleigh-Taylor RT) and when they go up, they evolve along magnetic field lines and reach about 200 Equator North and South magnetic latitude. These irregularities of ionospheric plasma causes the amplitude and phase scintillation in the electromagnetic signals that crosses the ionosphere. The scintillation amplitude of the signal is larger in regions with larger CET, for example, in AIE peaks. The Global Positioning System (GPS) that broadcast in the frequencies L1 (1.575 GHz) and L2 (1.227 GHz) provide new techniques to study ionospheric irregularities. In the INPE the ionosphric irregularities study using GPS, began in 1997 with Cornell University collaboration and FAPESP support under the process &.Still FAPESP support, in 2007, process 2006/06585-7, it was implemented a monitoring and mapping system of TEC and ionospheric scintillation in real time, available in the site: www.inpe.br/scintec. The proposed goals main were reached, however we aim the necessity to do some customizing for the system to become more efficient and robust.We describe these customizing like the development of one methodology for S4 index calculation which should be applied to different models of GPS receivers; the establisment of one automatized data backup system, to create a metadata to control the receiving of files from different GPS receivers and to develop the data qualification and the sscripts to for the data extraction to be automatized in agreement with the RINEX and RINEX2 formats, to migrate the the databank from MySQL to POSTGRESS, to model the relational data and to study the magnetic effect over the TEC. Yet to improve the ionospheric scintillation prediction and TEC through data mining.Once the robust and affordable scintillation and TEC real time system is established over Brazil, it will become easy to reach the objectives to provide services to the community like the TEC and scintillation data maps in real time, and to provide these data through assimilation for a low latitude ionospheric model. It will be possible to use the TEC gradients to help the Space Weather Project that was recently established and also to reach the scientific objectives like the ionospheric behavior during magnetic storms, solar cycle effects, season, local time and geomagnetic position over the TEC and scintillations. (AU)