AbstractF-region vertical plasma drift velocities were deduced from the hourly hmF2 values acquired from ionogram data over a near dip equatorial station Ouagadougou (12.4°N, 358.5°E, dip angle 5.9°N) in Africa. Our results are compared against the global empirical model of Scherliess and Fejer (1999) incorporated in the IRI model (IRI-2007) for 1600 to 0800 LT from 1year of data during sunspot maximum year of 1989 (yearly average solar flux intensity, F10.7=192) corresponding to the peak phase of solar cycle 22, under magnetically quiet conditions. The drifts are entirely downward between 2000 and 0500 LT bin for both techniques and the root mean square error (RMSE) between the modeled and the ionosonde vertical plasma drifts during these periods is 3.80, 4.37, and 4.74m/s for June solstice, December solstice and equinox, respectively. Ouagadougou average vertical drifts show evening prereversal enhancement (PRE) velocity peaks (VZP) of about 16, 14, and 17m/s in June solstice, December solstice, and equinox, respectively, at 1900–2000 LT; whereas global empirical model average drifts indicate VZP of approximately 33m/s (June solstice), 29m/s (December solstice), and 50m/s (equinox) at 1800 LT. We find very weak and positive correlation (+0.10376) between modeled VZP versus F10.7, while ionosonde VZP against F10.7 gives worst and opposite correlation (−0.05799). The results also show that modeled VZP–Ap indicates good and positive correlation (+0.64289), but ionosonde VZP–Ap exhibits poor and negative correlation (−0.22477).
Equatorial vertical E×B drift velocities inferred from ionosonde measurements over Ouagadougou and the IRI-2007 vertical ion drift model
Advances in Space Research ; 46 , 5 ; 604-612
2010-04-01
9 pages
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch
Vertical drift velocity in the daytime F-region at lbadan estimated from ionosonde data
Online Contents | 2006
|