scholarly journals Lidar observations of persistent gravity waves with periods of 3–10 h in the Antarctic middle and upper atmosphere at McMurdo (77.83°S, 166.67°E)

2016 ◽  
Vol 121 (2) ◽  
pp. 1483-1502 ◽  
Author(s):  
Cao Chen ◽  
Xinzhao Chu ◽  
Jian Zhao ◽  
Brendan R. Roberts ◽  
Zhibin Yu ◽  
...  
Keyword(s):  
Gravity Waves ◽  
Upper Atmosphere ◽  
The Antarctic ◽  
Lidar Observations

Investigation of acoustic gravity waves in the upper atmosphere by the artificial periodic inhomogeneities method at Nizhny Novgorod

1996 ◽  
Vol 39 (3) ◽  
pp. 224-228
Author(s):  
N. V. Bakhmet'eva ◽  
V. V. Belikovich ◽  
E. A. Benediktov ◽  
V. N. Bubukina ◽  
N. P. Goncharov ◽  
...  
Keyword(s):  
Gravity Waves ◽  
Upper Atmosphere ◽  
Acoustic Gravity Waves ◽  
Periodic Inhomogeneities

scholarly journals Can gravity waves significantly impact PSC occurrence in the Antarctic?

2009 ◽  
Vol 9 (22) ◽  
pp. 8825-8840 ◽  
Author(s):  
A. J. McDonald ◽  
S. E. George ◽  
R. M. Woollands
Keyword(s):  
Antarctic Peninsula ◽  
Gravity Waves ◽  
Clustering Algorithm ◽  
Small Scale ◽  
Temperature Threshold ◽  
Aerosol Extinction ◽  
Polar Stratospheric Clouds ◽  
Mountain Wave ◽  
Stratospheric Clouds ◽  
The Antarctic

Abstract. A combination of POAM III aerosol extinction and CHAMP RO temperature measurements are used to examine the role of atmospheric gravity waves in the formation of Antarctic Polar Stratospheric Clouds (PSCs). POAM III aerosol extinction observations and quality flag information are used to identify Polar Stratospheric Clouds using an unsupervised clustering algorithm. A PSC proxy, derived by thresholding Met Office temperature analyses with the PSC Type Ia formation temperature (TNAT), shows general agreement with the results of the POAM III analysis. However, in June the POAM III observations of PSC are more abundant than expected from temperature threshold crossings in five out of the eight years examined. In addition, September and October PSC identified using temperature thresholding is often significantly higher than that derived from POAM III; this observation probably being due to dehydration and denitrification. Comparison of the Met Office temperature analyses with corresponding CHAMP observations also suggests a small warm bias in the Met Office data in June. However, this bias cannot fully explain the differences observed. Analysis of CHAMP data indicates that temperature perturbations associated with gravity waves may partially explain the enhanced PSC incidence observed in June (relative to the Met Office analyses). For this month, approximately 40% of the temperature threshold crossings observed using CHAMP RO data are associated with small-scale perturbations. Examination of the distribution of temperatures relative to TNAT shows a large proportion of June data to be close to this threshold, potentially enhancing the importance of gravity wave induced temperature perturbations. Inspection of the longitudinal structure of PSC occurrence in June 2005 also shows that regions of enhancement are geographically associated with the Antarctic Peninsula; a known mountain wave "hotspot". The latitudinal variation of POAM III observations means that we only observe this region in June–July, and thus the true pattern of enhanced PSC production may continue operating into later months. The analysis has shown that early in the Antarctic winter stratospheric background temperatures are close to the TNAT threshold (and PSC formation), and are thus sensitive to temperature perturbations associated with mountain wave activity near the Antarctic peninsula (40% of PSC formation). Later in the season, and at latitudes away from the peninsula, temperature perturbations associated with gravity waves contribute to about 15% of the observed PSC (a value which corresponds well to several previous studies). This lower value is likely to be due to colder background temperatures already achieving the TNAT threshold unaided. Additionally, there is a reduction in the magnitude of gravity waves perturbations observed as POAM III samples poleward of the peninsula.

scholarly journals Rayleigh/Raman lidar observations of gravity wave activity from 15 to 70 km altitude over Syowa (69°S, 40°E), the Antarctic

2017 ◽  
Vol 122 (15) ◽  
pp. 7869-7880 ◽  
Author(s):  
Masaru Kogure ◽  
Takuji Nakamura ◽  
Mitsumu K. Ejiri ◽  
Takanori Nishiyama ◽  
Yoshihiro Tomikawa ◽  
...  
Keyword(s):  
Gravity Wave ◽  
Wave Activity ◽  
Raman Lidar ◽  
The Antarctic ◽  
Lidar Observations

scholarly journals Gravity Waves Drive Global Changes in Earth's Upper Atmosphere

Eos ◽  
2015 ◽  
Vol 96 ◽  
Author(s):  
Eric Betz
Keyword(s):  
Gravity Waves ◽  
Upper Atmosphere ◽  
Global Changes

Deep convective objects such as the plumes in thunderstorms can trigger gravity waves, which disturb the wind and temperatures hundreds of kilometers above Earth's surface.

scholarly journals Growth Rate of Gravity Wave Amplitudes Observed in Sodium Lidar Density Profiles and Nightglow Image Data

2019 ◽  
Author(s):  
Fabio Vargas ◽  
Guotao Yang ◽  
Paulo Batista ◽  
Delano Gobbi
Keyword(s):  
Growth Rate ◽  
Gravity Wave ◽  
Gravity Waves ◽  
Growth Rates ◽  
Image Data ◽  
Dynamic Parameters ◽  
Density Profiles ◽  
Wave Dynamic ◽  
Lidar Observations ◽  
Amplitude Growth

Amplitude growth rates of monochromatic gravity waves were estimated and compared from multiple instrument measurements carried out in Brazil. Wave dynamic parameters were obtained from sodium density profiles from lidar observations carried out in Sao Jose dos Campos (23°S, 46°W), while all-sky images of multiple airglow layers provided amplitudes and parameters of waves over Cachoeira Paulista (23°S, 45°W). Growth rates of gravity wave amplitudes from lidar and airglow imager data were consistent with dissipative wave behavior. Only a small amount of the observed wave events presented freely propagating behavior. Part of the observed waves presented saturated amplitude. The general saturated/damped behavior is consistent with diffusive filtering processes imposing limits to amplitude growth rates of the observed gravity waves.

Global circulation of Mars’ upper atmosphere

Science ◽  
2019 ◽  
Vol 366 (6471) ◽  
pp. 1363-1366 ◽  
Author(s):  
M. Benna ◽  
S. W. Bougher ◽  
Y. Lee ◽  
K. J. Roeten ◽  
E. Yiğit ◽  
...  
Keyword(s):  
Gravity Waves ◽  
Incident Energy ◽  
Upper Atmosphere ◽  
The Sun ◽  
Mars Atmosphere ◽  
Neutral Winds ◽  
Global Circulation ◽  
Structure And Dynamics ◽  
Circulation Patterns

The thermosphere of Mars is the interface through which the planet is continuously losing its reservoir of atmospheric volatiles to space. The structure and dynamics of the thermosphere is driven by a global circulation that redistributes the incident energy from the Sun. We report mapping of the global circulation in the thermosphere of Mars with the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft. The measured neutral winds reveal circulation patterns simpler than those of Earth that persist over changing seasons. The winds exhibit pronounced correlation with the underlying topography owing to orographic gravity waves.

Vertical Propagation of Acoustic-Gravity Waves from Atmospheric Fronts into the Upper Atmosphere

2019 ◽  
Vol 55 (4) ◽  
pp. 303-311
Author(s):  
Y. A. Kurdyaeva ◽  
S. N. Kulichkov ◽  
S. P. Kshevetskii ◽  
O. P. Borchevkina ◽  
E. V. Golikova
Keyword(s):  
Gravity Waves ◽  
Upper Atmosphere ◽  
Acoustic Gravity Waves ◽  
Atmospheric Fronts ◽  
Vertical Propagation

scholarly journals The Atmospheric Limitation on the Precision of Ground-Based Astrometry

1995 ◽  
Vol 166 ◽  
pp. 371-371
Author(s):  
I.S. Guseva
Keyword(s):  
Spectral Analysis ◽  
Gravity Waves ◽  
Systematic Errors ◽  
Upper Atmosphere ◽  
Random Errors ◽  
Critical Problem ◽  
Pulkovo Observatory ◽  
Long Period ◽  
Wide Range ◽  
Period Variations

Anomalous refraction remains to be the most critical problem in the meridian astrometry measuring large angles on the sky. I study slow quasi-periodical variations of refraction caused by the processes in the middle and upper atmosphere, such as gravity waves, etc., which can not be detected and calibrated out by use of any on-ground meteorological measurements. For this study, very old observations at large zenith distances of 80 to 90 degrees made by V. Fuss at Pulkovo Observatory in 1867-1869 [1] were used. The Deeming's method [2] of spectral analysis of data was applied to examine the characteristic variations of refraction in a wide range of periods. Very powerful quasi-periodical processes with periods of 7-8, 11-14, 18-22, 36-44 minutes and with amplitudes of 0.3 to 0.5 arcsec in the zenith were found when short sets of observations (1-5 days) were considered. They increase random errors of astrometric observations with meridian circles, transit instruments, astrolabes, etc. The periods of very slow variations — 152, 122, 93, 82.5, 73, 61 and 50 days, – are close to the well known periods discovered in other astronomical phenomena, for instance, in solar activity and in Earth rotation. I note also, that some of the long-period variations of refraction may cause quasi-systematic errors in astrometric measurements and catalogues.

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