Caracterização dos parâmetros de ondas de gravidade detectadas por imagem de aeroluminescência sobre São João do Cariri (7º S, 36ºW).

Abstract

The goal of this work consist in determining physical parameters of short period gravity waves detected by an all-sky imager at S. J do Cariri, an equatorial site. The OH airglow data were collected from September 2000 to August 2001, except on March 2001 when the imager presented electronic problem. In order to obtain a picture about these waves detected at S. J do Cariri (7°S, 36°W), a comparison between this site and Cachoeira Paulista, SP (23.5°S, 45°W) (hereafter CP) was made. Physical parameters, such as: horizontal phase velocity and direction of propagation, observed period and horizontal wavelength, were determined through a sequence of imager. The waves detected at S. J do Cariri presented some differences in comparison with those ones detected at CP. The number of ripples detected at S. J do Cariri, e.g., was larger than that one observed at CP. On the other hand, the number of detected band at S. J do Cariri was smaller than that one observed at CP. At Cariri, on average, the direction of propagation presented a seasonal behavior and the phase velocity detected was bigger than at CP. The horizontal wavelength and observe period detected at S. J do Cariri ranged from 5 to 60 km and 5 to 60 minute, respectively.