Characterization of medium-scale traveling ionospheric disturbances in the brazilian low latitude sector - Statistical Analysis of All-Sky Images of oi 630 nm airglow emission

Danielle Cristina de Morais Amorim, Alexandre Alvares Pimenta, Aline Amorim de Almeida

Abstract


In order to characterize the phenomenon known as Medium-Scale Traveling Ionospheric Disturbances (MSTIDs), we present in this paper the results
obtained from the statistical analysis of 10.5 years all-sky images of OI 630 nm airglow emission over the Brazilian low latitude sector. The images, which were obtained
by an all-sky imager installed at Cachoeira Paulista (22.7â—¦S, 45â—¦W), show dark band structures propagating from southeast to northwest with velocities of 50-200 m/s.
Our results show the greatest occurrence of MSTIDs during solar minimum and a minor occurrence rate during descending and ascending solar activity periods. During
solar maximum activity we have not detected MSTIDs signatures on all-sky images. In relation to seasonality, the greatest frequency of occurrence is during local winter.
All detected events have occurred during geomagnetically quiet conditions (Kp<3). Possible mechanisms of generation of this phenomenon are discussed.

Full Text:

PDF


DOI: http://dx.doi.org/10.22564/rbgf.v30i2.86







Brazilian Journal of Geophysics - BrJG (online version): ISSN 2764-8044
a partir do v.30n.1 (2012) até o presente

Revista Brasileira de Geofísica - RBGf (online version): ISSN 1809-4511
v.15n.1 (1997) até v.29n.4 (2011)

Revista Brasileira de Geofísica - RBGf (printed version): ISSN 0102-261X
v.1n.1 (1982) até v.33n.1 (2015)

 

Brazilian Journal of Geophysics - BrJG
Sociedade Brasileira de Geofísica - SBGf
Av. Rio Branco 156 sala 2509
Rio de Janeiro, RJ, Brazil
Phone/Fax: +55 21 2533-0064
E-mail: editor@sbgf.org.br