Analysis and interpretation of airglow and radar observations of quasi-monochromatic gravity waves in the upper mesosphere and lower thermosphere over Adelaide, Australia (35°S, 138°E)

Walterscheid, R. L.; Hecht, J. H.; Vincent, R. A.; Reid, Iain M.; Woithe, J. M.; Hickey, Michael P.

doi:10.1016/s1364-6826(99)00002-4

Cited by 168 publications

(300 citation statements)

References 35 publications

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“…Other studies yielded direct evidence for local instabilities suggesting GW "breaking," dissipation, and energy and momentum deposition [e.g., Swenson and Mende, 1994;Hecht et al, 1997;Yamada et al, 2001;Xu et al, 2006;Li et al, 2005Li et al, , 2007. Evidence of GW ducting behavior in the MLT has also been obtained [e.g., Isler et al, 1997;Walterscheid et al, 1999;Simkhada et al, 2009], including large-amplitude events now recognized as mesospheric bores [Taylor et al, 1995a;Dewan et al, 1998;Dewan and Picard, 2001;Medeiros et al, 2001Medeiros et al, , 2005Smith et al, 2003Smith et al, , 2005Smith et al, , 2006She et al, 2004;Fechine et al, 2005;Nielsen et al, 2006;Stockwell et al, 2006Stockwell et al, , 2011Narayanan et al, 2009;Bageston et al, 2011aBageston et al, , 2011bLi et al, 2013].…”

Section: Introductionmentioning

confidence: 99%

Investigation of a mesospheric gravity wave ducting event using coordinated sodium lidar and Mesospheric Temperature Mapper measurements at ALOMAR, Norway (69°N)

et al. 2014

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New measurements at the ALOMAR observatory in northern Norway (69°N, 16°E) using the Weber sodium lidar and the Advanced Mesospheric Temperature Mapper (AMTM) allow for a comprehensive investigation of a gravity wave (GW) event on 22 and 23 January 2012 and the complex and varying propagation environment in which the GW was observed. These observational techniques provide insight into the altitude ranges over which a GW may be evanescent or propagating and enable a clear distinction in specific cases. Weber sodium lidar measurements provide estimates of background temperature, wind, and stability profiles at altitudes from~78 to 105 km. Detailed AMTM temperature maps of GWs in the OH emission layer together with lidar measurements quantify estimates of the observed and intrinsic GW parameters centered near 87 km. Lidar measurements of sodium densities also allow more precise identification of GW phase structures extending over a broad altitude range. We find for this particular event that the extent of evanescent regions versus regions allowing GW propagation can vary largely over a period of hours and significantly change the range of altitudes over which a GW can propagate.

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Section: Introductionmentioning

confidence: 99%

Investigation of a mesospheric gravity wave ducting event using coordinated sodium lidar and Mesospheric Temperature Mapper measurements at ALOMAR, Norway (69°N)

et al. 2014

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“…Nakamura et al, 1999;Walterscheid et al, 1999;Hecht et al, 2001), some with strong meridional anisotropy. Walterscheid et al (1999) suggested this could be due to wave ducting rather than wind filtering effects. Ducting can occur due to shears in the background winds in the MLT region (termed Doppler ducting) or to changes in the local temperature gradient (termed thermal or Brunt ducting).…”

Section: Gravity Wave Anisotropymentioning

confidence: 99%

Recent progress in mesospheric gravity wave studies using nigthglow imaging system

Taylor¹,

Pendleton²,

Pautet³

et al. 2007

Rev. Bras. Geof.

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ABSTRACT.A variety of optical remote sensing techniques have now revealed a rich spectrum of wave activity in the upper atmosphere. Many of these perturbations, with periodicities ranging from ∼5 min to many hours and horizontal scales of a few tens of km to several thousands km, are due to freely propagating atmospheric gravity waves and forced tidal oscillations. Passive optical observations of the spatial and temporal characteristics of these waves in the mesosphere and lower thermosphere (MLT) region (∼80-100 km) are facilitated by several naturally occurring, vertically distinct nightglow layers. This paper describes the use of state-of-the-art groundbased CCD imaging techniques to detect these waves in intensity and temperature. All-sky (180 • ) image measurements are used to illustrate the characteristics of small-scale, short period (<1 hour) waves and to investigate their seasonal propagation and momentum impact on the MLT region. These results are then contrasted with measurements of mesospheric temperature made using a new temperature mapping imaging system capable of determining induced temperature amplitudes of a large range of wave motions and investigating night-to-night and seasonal variability in mesospheric temperature.Keywords: gravity waves, mesospheric dynamics, airglow imaging, seasonal variability. RESUMO.O espectro de ondas na alta atmosfera tem sido revelado por uma variedade de técnicas de sensoriamento remotoótico. Muitas destas perturbações apresentam períodos variando de 5 minutos a algumas horas e escalas horizontais que variam de dezenas a milhares de quilômetros e são devidas a livre propagação de ondas de gravidade e marés atmosféricas. Observaçõesóticas das características espacial e temporal destas ondas na região (∼80-100 km) da mesosfera e baixa termosfera (MLT) utilizam a variação da aeroluminescência atmosférica. Este trabalho descreve o estado da arte das técnicas que utilizam o imageamento via CCD para detectar estas ondas através das variações provocadas na intensidade e temperatura. Medidas de um imageador de céu todo (All-sky, 180 • ) são usadas parar determinar as características de ondas de pequena escala e curto período (<1 hora) e investigar a sazonalidade da direção propagação destas ondas, como também o depósito de momento na região da MLT. Estes resultados são comparados com medidas da temperatura atmosférica realizadas usando um novo sistema de imageamento de mapeamento da temperatura mesosférica capaz de determinar variações nas amplitudes da temperatura provocadas pelas ondas de gravidade através da investigação da variabilidade noturna da temperatura mesosférica.

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“…Clairemidi et al, 1985). These patterns have been attributed to freely propagating or ducted short-period gravity waves (Walterscheid et al, 1999;Isler et al, 1997;Taylor et al, 1987). On the other hand, ripples are short-lived (<45 min), small-scale wave patterns of restricted spatial extent (Peterson, 1979), and are thought to be generated in-situ by localized shear or convective-type instabilities in the background wind field (Taylor and Hapgood, 1990;Hecht et al, 1995;Hecht, 2004).…”

Section: Introductionmentioning

confidence: 99%

“…Hecht et al (2001) mentioned that most of the waves observed at Urbana (40 • N, 88 • W), during the summer solstice, originated from the south or southeast. Walterscheid et al (1999) concluded, from 9 months of airglow image observations at Adelaide (35 • S, 138 • E), that many waves were thermally ducted and for waves with horizontal wavelengths of a few tens of kilometers, the preferential propagation direction was poleward in summer and equatorward in winter. Medeiros et al (2003) reported that the propagation direction of the bands observed at Cachoeira Paulista (22.7 • S, 45.0 • W) also showed a seasonal variation.…”

Section: Introductionmentioning

confidence: 99%

MLT gravity wave climatology in the South America equatorial region observed by airglow imager

et al. 2007

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Abstract. An all-sky CCD imager for OH, O 2 and OI (557.7 nm) airglow emission measurements was operated at São João do Cariri (Cariri), Brazil (7 • S, 36 • W), from October 2000 to December 2004. A large amount of image data, more than 3000 h of observation and around 1000 wave events, makes it possible to classify the gravity wave characteristics, which are statistically significant. The observed waves show a typically short horizontal wavelength (5-45 km) and a short period (5-35 min), and horizontal phase speeds of 1 to 80 m/s. In most cases band-type waves (horizontal wavelength between 10 and 60 km) showed a clear preference for the horizontal propagation direction from the South American continent to the Atlantic Ocean. Ripples also have similar features but with different anisotropy. In this paper we focus our discussion on the wave characteristics of the bands and ripples and a comparison between them.

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Analysis and interpretation of airglow and radar observations of quasi-monochromatic gravity waves in the upper mesosphere and lower thermosphere over Adelaide, Australia (35°S, 138°E)

Cited by 168 publications

References 35 publications

Investigation of a mesospheric gravity wave ducting event using coordinated sodium lidar and Mesospheric Temperature Mapper measurements at ALOMAR, Norway (69°N)

Investigation of a mesospheric gravity wave ducting event using coordinated sodium lidar and Mesospheric Temperature Mapper measurements at ALOMAR, Norway (69°N)

Recent progress in mesospheric gravity wave studies using nigthglow imaging system

MLT gravity wave climatology in the South America equatorial region observed by airglow imager

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