Thermospheric meridional wind control of equatorial spread F and evening prereversal electric field

The role of the evening prereversal zonal electric field enhancement (PRE) as conducive to equatorial spread F (ESF)/plasma bubble development versus that of the magnetic meridional wind as a suppressing factor is examined using digital ionosonde data from an equatorial site, Sao Luis (SL), and a low latitude site, Cachoeira Paulista (CP) in Brazil. The evening vertical plasma drift (Vz) over SL is used, together with the F layer peak height (hmF2) over CP, to compute the magnetic meridional wind. The analysis performed for two epochs, that is, March‐April of 1999 and 2001, provide consistent evidence that the magnetic meridional wind can negatively influence the ESF development in two ways: (a) by reduced development of the PRE and. (b) by direct suppression of the bubble growth