%0 Conference Proceedings
%4 sid.inpe.br/mtc-m21c/2021/03.24.11.32
%2 sid.inpe.br/mtc-m21c/2021/03.24.11.32.07
%T Concentric Gravity waves observed by OH airglow over São João do Cariri
%D 2021
%A Nyassor, Prosper Kwamla,
%A Wrasse, Cristiano Max,
%A Gobbi, Delano,
%A Takahashi, Hisao,
%A Bageston, José Valentin,
%A Kleber, P. N.,
%A Batista, Paulo Prado,
%A Barros, Diego Prado,
%A Figueiredo, Cosme Alexandre Oliveira Barros,
%A Buriti, R. A.,
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Universidade Federal de Campina Grande (UFCG)
%@electronicmailaddress pnyassor@gmail.com
%@electronicmailaddress cristiano.wrasse@inpe.br
%@electronicmailaddress delano.gobbi@uol.com.br
%@electronicmailaddress
%@electronicmailaddress jose.bageston@inpe.br
%@electronicmailaddress
%@electronicmailaddress paulopradobatista@yahoo.com
%@electronicmailaddress dprado114@gmail.com
%@electronicmailaddress anagetinga@hotmail.com
%B Simpósio Brasileiro de Geofísica Espacial e Aeronomia, 8 (SBGEA)
%C Online
%8 22-26 mar.
%X Observation of concentric/circular gravity waves (CGWs) in the OH airglow emission over the Brazilian equatorial region. An all-sky imager located at Sao Joao do Cariri [7.39◦S, 36.53◦W] was used in the acquisition of the images. Using 20 years of observational data (between 1998 and 2018), 1052 nights of airglow observations were taken. However, only 5 CGW(s) cases were found with small-scale wave characteristics. The CGW(s) events showed horizontal wavelengths between 25 and 31km, horizontal phase speed between 42 and 75m/s and periods ranging from 7 to 11 minutes. Most of the CGW structures were well defined with coherent wave patterns expanding concentrically with all observed cases having semi-circle or arc-like shapes. The occurrence of CGWs was found to coincide mostly with the seasons of strong tropospheric convective activity as well as low background winds. This suggested a low level of wave breaking or critical level absorption/filtering/reflection, allowing the CGWs to propagate up to the mesosphere and lower thermosphere (MLT) region.
%@language en