@Article{VadasTPSFLSRBT:2009:LiSoMe,
author = "Vadas, S. L. and Taylor, M. J. and Pautet, P. D. and Stamus, P. A.
and Fritss, D. C. and Liu, H. L. and Sabbas, Fernanda Tavares
S{\~a}o and Rampinelli, V. T. and Batista, Paulo Prado and
Takahashi, Hisao",
affiliation = "{} and {} and {} and {} and {} and {} and {Instituto Nacional de
Pesquisas Espaciais (INPE)} and {} and {Instituto Nacional de
Pesquisas Espaciais (INPE)} and {Instituto Nacional de Pesquisas
Espaciais (INPE)}",
title = "Convection: the likely source of the medium-scale gravity waves
observed in the OH airglow layer near Brasilia, Brazil, during the
SpreadFEx campaign",
journal = "Annales Geophysicae",
year = "2009",
volume = "27",
number = "1",
pages = "231--259",
keywords = "Atmospheric composition and structure, Airglow and aurora, General
or miscellaneous.",
abstract = "Six medium-scale gravity waves (GWs) with horizontal wavelengths
of lambda(H) = 60-160 km were detected on four nights by Taylor et
al. (2009) in the OH airglow layer near Brasilia, at 15 degrees S,
47 degrees W, during the Spread F Experiment (SpreadFEx) in Brazil
in 2005. We reverse and forward ray trace these GWs to the
tropopause and into the thermosphere using a ray trace model which
includes thermospheric dissipation. We identify the convective
plumes, convective clusters, and convective regions which may have
generated these GWs. We find that deep convection is the highly
likely source of four of these GWs. We pinpoint the specific deep
convective plumes which likely excited two of these GWs on the
nights of 30 September and 1 October. On these nights, the source
location/time uncertainties were small and deep convection was
sporadic near the modeled source locations. We locate the regions
containing deep convective plumes and clusters which likely
excited the other two GWs. The last 2 GWs were probably also
excited from deep convection; however, they must have been ducted
similar to 500-700 km if so. Two of the GWs were likely
downwards-propagating initially (after which they reflected
upwards from the Earth's surface), while one of the GWs was likely
upwards-propagating initially from the convective plume/cluster.
We also estimate the amplitudes and vertical scales of these waves
at the tropopause, and compare their scales with those from a
simple, linear convection model. Finally, we calculate each GW's
dissipation altitude, location, and amplitude. We find that the
dissipation altitude depends sensitively on the winds at and above
the OH layer. We also find that several of these GWs may have
penetrated to high enough altitudes to potentially seed equatorial
spread F (ESF) if located somewhat farther from the magnetic
equator.",
issn = "0992-7689",
language = "en",
targetfile = "Convection the likely source of the medium-scale gravity
waves.htm",
urlaccessdate = "01 maio 2024"
}