Multi-year observations of gravity wave momentum fluxes at low and middle latitudes inferred by all-sky meteor radar

Autor(es)

Andrioli, V. F. ^[1] ; Batista, P. P. ^[1] ; Clemesha, B. R. ^[1] ; Schuch, N. J. ^[2] ; Buriti, R. A. ^[3]

Afiliação do(s) autor(es)

^[1] Inst Nacl Pesquisas Espaciais, BR-12201 Sao Jose Dos Campos, SP - Brazil

^[2] Ctr Reg Sul Pesquisas Espaciais, Santa Maria, RS - Brazil

^[3] Univ Fed Campina Grande, Campina Grande, PB - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Annales Geophysicae; v. 33, n. 9, p. 1183-1193, 2015.
• Citações Web of Science: 6

Resumo

We have applied a modified composite day analysis to the Hocking (2005) technique to study gravity wave (GW) momentum fluxes in the mesosphere and lower thermosphere (MLT). Wind measurements from almost continuous meteor radar observations during June 2004-December 2008 over Sao Joao do Cariri (Cariri; 7A degrees S, 36A degrees W), April 1999-November 2008 over Cachoeira Paulista (CP; 23A degrees S, 45A degrees W), and February 2005-December 2009 over Santa Maria (SM; 30A degrees S, 54A degrees W) were used to estimate the GW momentum fluxes and variances in the MLT region. Our analysis can provide monthly mean altitude profiles of vertical fluxes of horizontal momentum for short-period (less than 2-3 h) GWs. The averages for each month throughout the entire data series have shown different behavior for the momentum fluxes depending on latitude and component. The meridional component has almost the same behavior at the three sites, being positive (northward), for most part of the year. On the other hand, the zonal component shows different behavior at each location: it is positive for almost half the year at Cariri and SM but predominantly negative over CP. Annual variation in the GW momentum fluxes is present at all sites in the zonal component and also in SM at 89 km in the meridional component. The seasonal analysis has also shown a 4-month oscillation at 92.5 km over SM in the zonal component and over CP at the same altitudes but for the meridional component. (AU)

• Processo FAPESP: 12/08769-9 - Estudo das Ondas de Gravidade na Região da Mesosfera e Baixa Termosfera Utilizando Radar Meteórico, Radar de laser e Imageadores CCD All-Sky
• Beneficiário: Vânia Fátima Andrioli Novaes Silva
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado