Vertical winds and 3-4 day momentum flux in the MLT inferred from meteor radar measurements

PreviousNext No Access14th International Congress of the Brazilian Geophysical Society & EXPOGEF, Rio de Janeiro, Brazil, 3-6 August 2015Vertical winds and 3-4 day momentum flux in the MLT inferred from meteor radar measurementsAuthors: Fábio EgitoPaulo P. BatistaBarclay R. ClemeshaRicardo A. BuritiFábio EgitoUniversidade Federal do Oeste da Bahia-UFOBSearch for more papers by this author, Paulo P. BatistaInstituto Nacional de Pesquisas EspaciaisSearch for more papers by this author, Barclay R. ClemeshaInstituto Nacional de Pesquisas EspaciaisSearch for more papers by this author, and Ricardo A. BuritiUniversidade Federal da Campina Grande-UFCGSearch for more papers by this authorhttps://doi.org/10.1190/sbgf2015-289 SectionsAboutPDF/ePub ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InRedditEmail Abstract Planetary scale waves in equatorial region transport a significant amount of energy and momentum through atmosphere. Quantifying the momentum transported by these waves and its effects toward the mean flow is rather important. Direct estimative of the momentum flux transported by these waves requires horizontal and vertical wind measurements. Ground-based meteor radars have provided continuous and reliable measurements of the horizontal wind components in the MLT region. On the other hand, vertical wind component does not present the same reliability. However, an approach presented by Babu et al. (2012), made possible to calculate tridimensional daily winds by using only near zenith echoes detected around their maximum counting rate, i.e., during early morning hours. From daily tridimensional winds, momentum fluxes due to planetary scale waves can be estimated. Following this approach, we have used measurements performed by a meteor radar installed at São João do Cariri (7.4ºS; 36.5ºW) in order to measure vertical winds and after determine the momentum flux transported by these waves. Vertical wind presents magnitudes of a few meters per second and occasionally reaches magnitudes higher than 10 m/s. Below 92 km vertical wind is upward during the whole year and above exhibits a semi-annual oscillation with downward phase during the equinoxes. Variations associated to planetary scale waves in the vertical wind are also observed and some of them appear simultaneously in the zonal and meridional wind. Vertical transport of zonal momentum fluxes of 3-4 day component is found to be maximum near autumn equinox, when its value reaches almost 20 m2s-2, while minimum momentum fluxes were observed before winter solstice. Keywords: winds, flux, South AmericaPermalink: https://doi.org/10.1190/sbgf2015-289FiguresReferencesRelatedDetails 14th International Congress of the Brazilian Geophysical Society & EXPOGEF, Rio de Janeiro, Brazil, 3-6 August 2015ISSN (online):2159-6832Copyright: 2015 Pages: 1553 publication data© 2015 Published in electronic format with permission by the Brazilian Geophysical SocietyPublisher:Society of Exploration Geophysicists HistoryPublished Online: 06 Aug 2015 CITATION INFORMATION Fábio Egito, Paulo P. Batista, Barclay R. Clemesha, and Ricardo A. Buriti, (2015), "Vertical winds and 3-4 day momentum flux in the MLT inferred from meteor radar measurements," SEG Global Meeting Abstracts : 1450-1454. https://doi.org/10.1190/sbgf2015-289 Plain-Language Summary KeywordswindsfluxSouth AmericaPDF DownloadLoading ...