Open AccessClimatology of gravity waves–induced electric fields in the equatorial E region
Author(s) -
Aveiro H. C.,
Denardini C. M.,
Abdu M. A.
Publication year - 2009
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2009ja014177
Subject(s) - equatorial electrojet , electric field , electrojet , geophysics , physics , ionosphere , gravity wave , earth's magnetic field , magnetic field , geomagnetic latitude , geodesy , radar , computational physics , gravitational wave , geology , astrophysics , telecommunications , quantum mechanics , computer science
Equatorial electrojet (EEJ) observations using VHF radars show backscattered echoes from two types of electron density irregularities explained by the modified two‐stream (Type I) and the gradient drift (Type II) instabilities. From the Type II irregularity velocities obtained by a radar installed at São Luiz Space Observatory (2.58°S, 44.23°W, magnetic latitude 0.23°S) we have inferred the vertical electric fields ( E z ). The E z inference was based on geomagnetic field and atmospheric models. A harmonic analysis of these electric fields shows the presence of gravity waves (GW) induced oscillations in the EEJ. We calculated the ratio between GW‐related electric fields and the total E z , which is an indicator of the efficiency in the production of an additional electric field due to a gravity wave neutral wind. In the present paper we describe the methodology of analysis and discuss some characteristics of the gravity waves that could modify the equatorial ionospheric electric fields.