Abstract:
The daytime vertical E x B drift velocity plays a significant role on equatorial iono
sphere processes such as formation of equatorial ionization anomaly.
The equatorial
regi~n ionosphere, which exhibits very dynamic processes, has been less studied due
to lack of enough ionospheric monitoring instruments. Studies have been done on de
veloping climatological models
to represent the global equatorial region plasma drift
velocity using ground
and/or space based observations. The climatological empirical
ExB drift velocity model has been developed using limited Radar and Magnetometer
measurements taken in Peruvian sector. This model has not yet been validated in
detail using recently installed magnetometers
data taken in East-African region. In
addition, it is well known that such empirical model can only mimic the long time
trend of the data but not the physics behind. Therefore, in this thesis new technique
that can be used to estimate the ExB drift velocity and E region E-field using physics
based model derived from Ampere's
and Ohm's Law has been described. The differ
ence of
the daytime horizontal components of the geomagnetic field obtained (on quiet
days) from two magnetometers installed near
0° latitude and 6° latitude off the mag
netic equator in East-African sector has been used as
input to the physics based and
empirical models to reproduce drift velocity observed by C/NOFS (Communication
/ Navigation
Outage Forecast System) satellite while it passes over the East-African
region. In addition
the performances of the other E x B drift velocity (IRI) and E
'" region E-field empirical models have been examined by running the models at the
time and the position where we have measurements taken in the East-African sector.
We have found out that the drift velocity estimated using physics based model shows
