Earth Planets Space, Vol. 61 (No. 4), pp. 455-462, 2009
H. Takahashi1, M. A. Abdu1, C. M. Wrasse2, J. Fechine1, I. S. Batista1, D. Pancheva3, L. M. Lima4, P. P. Batista1, B. R. Clemesha1, K. Shiokawa5, D. Gobbi1, M. G. Mlynczak6, and J. M. Russell7
1Instituto Nacional de Pesquisas Espaciais, INPE, São José dos Campos, SP, Brazil
2IP&D, Universidade do Vale do Paraíba, UNIVAP, São José dos Campos, SP, Brazil
3Department of Electronic & Electrical Engineering, University of Bath, Bath, BA2 7AY, UK
4Departamento de Fisica, Universidade Estadual de Paraíba, Campina Grande, PB, Brazil
5Solar Terrestrial Environmental Laboratory, STEL, Nagoya University, Toyokawa, Aichi, Japan
6Atmospheric Sciences Division, NASA, Langley Research Center, Hampton, VA, USA
7Center for Atmospheric Sciences, Hampton University, Hampton, VA, USA
(Received October 23, 2007; Revised May 12, 2008; Accepted May 30, 2008; Online published May 14, 2009)
Equatorial 3.5-day ultra-fast Kelvin wave was observed in the MLT zonal wind measured by meteor radar at Cariri (7.4°S, 36.5°W, geomag. 8°S) and in the stratosphere-mesosphere temperature structures from the TIMED/SABER data. The ionospheric F-layer bottom-side virtual height h'F and the critical frequency foF2 observed at Fortaleza (3.9°S, 38.4°W, geomag. 5°S) also showed similar oscillation structures, indicating an influence of the Kelvin wave in the F region height and modulation of E × B uplifting during the evening period. Consequently the ionospheric spread F onset time was also modulated in the same period, around 4 days.
Key words: Equatorial ionosphere, mesosphere, planetary waves, Kelvin wave.