On equatorial geophysics studies : a review on the IGRGEA results during the last decade

摘要: Abstract During the years 1993–1994, a continuous campaign of measurements has been held in frame International Equatorial Electrojet Year (IEEY) with network 10 magneto-telluric stations and three ionosondes. Other instruments have participated during shorter periods, HF radar optical Fabry-Perot 630 nm interferometer. After IEEY campaigns, Group Research Geophysics Europe Africa (IGRGEA created January 1995), organized research geophysics. This paper report main results IGRGEA last decade at local, regional planetary scales. At local scale, data highlighted complex structure echoes equatorial zone allowed to explain “necklace” as due oblique propagation into type I instability levels. observed atmospheric storm electric field discharges Es layer for daytime Spread F night-time. A series original concern Doppler spectra change on plasma drifts across ionosphere, gravity waves effects well ESF multi-process sources. magnetic were used parametrize (EEJ). Ionospheric data, UARS satellite brought together input parameters Richmond's EEJ model reproduce variations associated EEJ. The comparisons between computed from physical parametrization are all good agreement. Ionosonde included IRI. revealed aligned f 0 2 crests ionization mid morning early afternoon hours. Measurements night-time wind variations, obtained first time over African interferometer, shown strong variability winds. was done using magnetometers chain involved longitude sectors. Finally, we present electrodynamic coupling high low latitudes overshielding or shielding events.