ANGEO - Abstract - Observations of equatorial mesospheric winds over Cariri (7.4° S) by a meteor radar and comparison with existing models

Ann. Geophys., 26, 485-497, 2008
www.ann-geophys.net/26/485/2008/
© European Geosciences Union 2008

Observations of equatorial mesospheric winds over Cariri (7.4° S) by a meteor radar and comparison with existing models

R. A. Buriti^1,*, W. K. Hocking², P. P. Batista³, A. F. Medeiros¹, and B. R. Clemesha³
¹Departamento de Fisica, Universidade Federal de Campina Grande, Campina Grande, PB, 58109-970, Brazil
²Department of Physics and Astronomy, University of Western Ontario, London, Ontario, Canada
³Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP, Brazil
^*now at: Department of Physics and Astronomy, UWO, London, Canada

Abstract. Mesospheric winds observed with a meteor radar at Cariri (7.4° S, 36.5° W), Brazil, during the period of July 2004 to June 2005, show a clear semiannual oscillation known as the Mesospheric Semiannual Oscillation (MSAO), which maximizes in the zonal mean wind mainly at 82 km, with amplitude decreasing with height. Maximum westward winds for the MSAO occurred in March and September. The meridional wind, on the other hand, presented a clear annual variation maximizing in December. On average, the amplitude of the meridional MSAO was smaller than the zonal MSAO component. Comparison with models shows on occasions that there are significant differences between the observed winds and the CIRA (Cospar International Reference Atmosphere) and HWM93 (Horizontal Wind Model) models. In addition, diurnal and semidiurnal parameters were calculated and compared to the GSWM model. Other results observed during one year of data are presented in this work.

Full Article in PDF (831 KB)