Studies of the traveling ionospheric disturbances of large and medium scale in the Brazilian sector during the period of ascension of the solar cycle 24.

Abstract

This post-doctoral proposal aims to study the traveling ionospheric disturbance (TID) in the equatorial and low latitudes in the Brazilian sector during the period of ascension of solar cycle 24 (2008-2013). The TIDs are irregularities in the ionospheric plasma spreading with speeds in the order of dozens to a few hundred meters per second. These disturbances have usually been observed moving for horizontal distances of thousands of kilometers in medium latitude regions. The TIDs can be divided into Large-Scale TIDs (LSTIDs) and Medium-Scale TIDs (MSTIDs). These scales of TIDs can favorably contribute to the generation, evolution, and dynamics of the equatorial spread F (ESF). This study will analyze the ionospheric observations obtained by Global Positioning System (GPS) receiving stations and by digital ionosonde stations located in the Brazilian sector during the period of ascension of the solar cycle 24. The GPS receiving stations, which belong to the Brazilian Network for Continuous GPS Monitoring (RBMC) and the network of the "Universidade do Vale do Paraíba (UNIVAP)", will be used to measure the total electron content (TEC). In addition, the observations of the digital ionosonde network operated by UNIVAP in São José dos Campos (SP), Palmas (TO), and Manaus (AM) will be analyzed. The proposed studies are extremely relevant to increase the understanding and comprehension of the dynamics and physical processes involved in large and medium scale traveling ionospheric disturbances and their relationship with ESFs observed in the Brazilian sector during geomagnetically quiet and disturbed periods.