Post-Sunset Uplifting of the Equatorial F Layer of the Ionosphere and Vertical Plasma Drift Velocities

The paper describes the comparison of individual measurements of the vertical plasma drift velocities in the F region of the ionosphere, VzF, computed from the doppler shift of 50MHz backscatter echoes at Jicamarca, Peru during the post-sunset hours with the corresponding values of the vertical velocity of the F layer computed from the rate of change of the minimum virtual height of the F layer, ∂h′minF/∂t, at Huancayo, Peru.It is found that there is a remarkable coincidence in the time of the reversal of vertical drift velocities of plasma measured by VHF incoherent radar and the F region vertical drift computed from the HF ionosonde. Statistically, the F layer vertical drift from ionogram data is about two-third of the incoherent scatter radar plasma drift velocities.Such a calibration would be greatly useful to study electric fields during sunset hours in the equatorial ionosphere at different longitudes where long series of ionospheric data are available.

[1]  B. V. Murthy.  Equatorial spread-F , 1993 .

[2]  R. G. Rastogi,et al.  On the occurrence of equatorial spread-F in the evening hours , 1986 .

[3]  M. A. Abdu,et al.  Equatorial F region vertical plasma drifts: Seasonal and longitudinal asymmetries in the American sector , 1986 .

[4]  I. Batista,et al.  Equatorial F-region irregularity latitudinal extension and dynamo electric field , 1985 .

[5]  M. A. Abdu,et al.  Magnetic declination control of the equatorial F region dynamo electric field development and spread F , 1981 .

[6]  H. Rishbeth.  The F-region dynamo , 1981 .

[7]  J. Bittencourt,et al.  IONIZATION DRIFT VELOCITIES IN THE EQUATORIAL F REGION , 1981 .

[8]  B. Fejer,et al.  Correction [to “Ionospheric irregularities”] , 1981 .

[9]  I. Batista,et al.  Some characteristics of spread F at the magnetic equatorial station Fortaleza , 1980 .

[10]  R. Rastogi.  On the equatorial spreadF , 1978, Proceedings / Indian Academy of Sciences.

[11]  H. Chandra,et al.  Electron density distribution over the magnetic equator , 1973 .

[12]  Henry Rishbeth,et al.  Polarization fields produced by winds in the equatorial F-region , 1971 .

[13]  Ronald F. Woodman,et al.  Equatorial spread F: Implications of VHF radar observations , 1970 .

[14]  Ronald F. Woodman,et al.  Vertical drift velocities and east‐west electric fields at the magnetic equator , 1970 .

[15]  I. Batista,et al.  Vertical ionization drift velocities and range type spread F in the evening equatorial ionosphere , 1983 .