Possible Tid Generated In The Polar Region And Observed On Equatorial Stations And Low Latitudes

During our research we detected and characterized LSTID (Large Scale Ionospheric Disturbances), in low latitudes, during intense geomagnetic storms and also the way they propagated. It was used ionospheric records obtained from digisondes of CADI type (Canadian Advanced Digital lonosonde) located in the city of Natal and DSP type (Digisonde Portable Souder) located in the cities of Cachoeira Paulista, Ramey and Eglin. The survey data from Ramey and Eglin were provided by Global Ionosphere Radio Observatory (GIRO). To observe the effects of storms on the polar ionosphere, auroral images of the North pole, obtained by the POLAR satellite, were used, which showed the intensification of auroral electrojet by the injection of particles in the cusps. The analyzed period included the days 6th and 7th, April 2000, and the indices used to characterize the magnetic activity in this period were Dst, Kp, and AE, in addition to the Bz component of the interplanetary magnetic field. The storm on April 6th had a Dstmin = -288 nT. geomagnetic storm are capable of affecting the behavior of all ionospheric plasma, thus affecting the operation of signal transmission stations in the telecommunications band and the altitude of satellites in that region. Anomalous behavior of the ionosphere was verified on the four cities, characterizing the propagation as being of type LSTID's, generated by the expansion of the auroral oval at the poles.