Abstract:
Vertical incidence ionospheric soundings with a C-3 ionosonde were performed at Kodaikanal (dip 3.5 deg N) at one minute intervals during October 1974-January 1975 with a view to monitoring the small scale fluctuations in the F-region critical frequency. The ionogram data showed the occurrence of blanketing sporadic-E layers during daytime conditions on five occasions. It is demonstrated that strong blanketing-layer type ionization irregularities can occasionally decay, in a span of about four minutes, at stations in the vicinity of the geomagnetic dip equator.
