Verification of GPS-TEC against South African Ionosonde data

Global vTEC map obtained with the NeQuick electron density model for a sunspot number of 150 at 13:00 UT in the month of April (grid resolution 2.5 degrees x 2.5 degrees). From

Project outline:
To produce Total Electron Content (TEC) maps such as that shown in the figure, over the South African region, using the GPS_TEC software, and GPS data from the Trignet network in South Africa.
To obtain concurrent TEC values from the 4 ionosondes in South Africa, and to compare the values of TEC at the ionosonde sites with values derived from the TEC-maps.
To statistically characterize the differences between the GPS TEC and the Ionosonde TEC.