VITAL, L. F. R.; http://lattes.cnpq.br/1747576741682740; VITAL, Luiz Fillip Rodrigues.
Resumo:
Atmospheric gravity waves are essential in to transport energy and momentum from the
middle to upper atmosphere. These waves are able to destabilize the hydrostatic balance
of the atmospheric fluid, in that the imbalance between the gravity and buoyancy acts
as the main restoring force. In this work, temperature data has been used, which were
collected by two Fabry-Perot interferometers (FPI), which measure emissions of the red
line of atomic oxygen - OI630.0 nm during the night, one located in São João do Cariri
(7,4 ◦ S; 36.5◦ W) and one in Cajazeiras (6.8 ◦ S; 38.5◦W) during 2013. Gravity wave
parameters were estimated, such as amplitude, period, horizontal wavelength and horizontal
phase propagation direction in the thermosphere-ionosphere region at altitude around
250 km. The Lomb-Scargle periodogram and wavelet analysis were used to determine
the parameters of the observed waves. To obtain amplitudes and phases, the data were
subjected to harmonic analysis using the least squares method. After analyzing 340 nights
for Cajazeiras and 346 for São João do Cariri, a total of 14 and 27 events were observed,
respectively, with wavelengths ranging from 18 to 938 km, with periods between 35.4 min
and 155.4 min, and mean amplitude ranging from 3.84 K to 130.6 K. It was also noted that
the observed waves propagated preferentially between the northeast and the southeast.