Response of Total Electron Content on the Low Latitude Vertical E x B Drift over Peruvian Sector

Abstract:

The equatorial region of the earth is a very appropriate place to study the seeding of the ionospheric irregularities because the magnetic field line is horizontal and thus perpendicular to gravity. Most ionospheric models use equatorial ExB drift velocities as an input parameter in order to predict the structures and dynamics of the ionosphere. Several studies have shown that the daytime vertical ExB drift can be inferred using ground based magnetometer observations. The dataset of horizontal component of the earth magnetic field obtained from a pair of magnetometers, one at the dip equator (Jicamarca) and another off the dip equator (Piura) by 6.8 degrees are analyzed and correlated with the ExB drift velocities measured by the Jicamarca Incoherent Scatter Radar(ISR). The impact of the pattern of equatorial ExB drift on Global Positioning System(GPS)-derived total electron content(TEC) has also been studied. Observational data from the recent solar minimum period (2008-09) for the day to day and seasonal variations of the drifts were examined. Linear regression and multilayer neural network approaches are used to analyze the data. Our study shows that the overall variation of daytime ExB drift during solar minimum can be inferred from ground based magnetometer observations. Observations show a noticeable connection between TEC value and the daytime ExB drift during low solar activity period. We compare the results from our investigation with Jicamarca ISR measurement and the Scherliess-Fejer empirical model on corresponding local time.