scholarly journals Secular variations of OI 5577 Å Airglow in the mesopause region induced by transient gravity wave packets

2001 ◽  
Vol 28 (4) ◽  
pp. 701-704 ◽  
Author(s):  
Michael P. Hickey ◽  
Richard L. Walterscheid
Keyword(s):  
Gravity Wave ◽  
Wave Packets ◽  
Mesopause Region ◽  
Secular Variations

scholarly journals Secular variations of atomic oxygen in the mesopause region induced by transient gravity wave packets

2000 ◽  
Vol 27 (21) ◽  
pp. 3599-3602 ◽  
Author(s):  
Michael P. Hickey ◽  
Richard L. Walterscheid ◽  
Philip G. Richards
Keyword(s):  
Gravity Wave ◽  
Atomic Oxygen ◽  
Wave Packets ◽  
Mesopause Region ◽  
Secular Variations

scholarly journals The nonlinear effects on the characteristics of gravity wave packets: dispersion and polarization relations

2000 ◽  
Vol 18 (10) ◽  
pp. 1316-1324 ◽  
Author(s):  
S.-D. Zhang ◽  
F. Yi ◽  
J.-F. Wang
Keyword(s):  
Gravity Wave ◽  
Gravity Waves ◽  
Middle Atmosphere ◽  
Wave Packets ◽  
Nonlinear Effects ◽  
Wave Theory ◽  
Nonlinear Propagation ◽  
Waves And Tides ◽  
Time Variations ◽  
Isothermal Atmosphere

Abstract. By analyzing the results of the numerical simulations of nonlinear propagation of three Gaussian gravity-wave packets in isothermal atmosphere individually, the nonlinear effects on the characteristics of gravity waves are studied quantitatively. The analyses show that during the nonlinear propagation of gravity wave packets the mean flows are accelerated and the vertical wavelengths show clear reduction due to nonlinearity. On the other hand, though nonlinear effects exist, the time variations of the frequencies of gravity wave packets are close to those derived from the dispersion relation and the amplitude and phase relations of wave-associated disturbance components are consistent with the predictions of the polarization relation of gravity waves. This indicates that the dispersion and polarization relations based on the linear gravity wave theory can be applied extensively in the nonlinear region.Key words: Meteorology and atmospheric dynamics (middle atmosphere dynamics; waves and tides)

scholarly journals Multi-instrument gravity-wave measurements over Tierra del Fuego and the Drake Passage – Part 1: Potential energies and vertical wavelengths from AIRS, COSMIC, HIRDLS, MLS-Aura, SAAMER, SABER and radiosondes

2016 ◽  
Vol 9 (3) ◽  
pp. 877-908 ◽  
Author(s):  
Corwin J. Wright ◽  
Neil P. Hindley ◽  
Andrew C. Moss ◽  
Nicholas J. Mitchell
Keyword(s):  
Gravity Wave ◽  
Wave Packets ◽  
Lower Thermosphere ◽  
Lower Troposphere ◽  
Drake Passage ◽  
Tierra Del Fuego ◽  
Data Sets ◽  
Meteor Radar ◽  
Diverse Range ◽  
Wide Range

Abstract. Gravity waves in the terrestrial atmosphere are a vital geophysical process, acting to transport energy and momentum on a wide range of scales and to couple the various atmospheric layers. Despite the importance of these waves, the many studies to date have often exhibited very dissimilar results, and it remains unclear whether these differences are primarily instrumental or methodological. Here, we address this problem by comparing observations made by a diverse range of the most widely used gravity-wave-resolving instruments in a common geographic region around the southern Andes and Drake Passage, an area known to exhibit strong wave activity. Specifically, we use data from three limb-sounding radiometers (Microwave Limb Sounder, MLS-Aura; HIgh Resolution Dynamics Limb Sounder, HIRDLS; Sounding of the Atmosphere using Broadband Emission Radiometry, SABER), the Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC) GPS-RO constellation, a ground-based meteor radar, the Advanced Infrared Sounder (AIRS) infrared nadir sounder and radiosondes to examine the gravity wave potential energy (GWPE) and vertical wavelengths (λz) of individual gravity-wave packets from the lower troposphere to the edge of the lower thermosphere ( ∼  100 km). Our results show important similarities and differences. Limb sounder measurements show high intercorrelation, typically  > 0.80 between any instrument pair. Meteor radar observations agree in form with the limb sounders, despite vast technical differences. AIRS and radiosonde observations tend to be uncorrelated or anticorrelated with the other data sets, suggesting very different behaviour of the wave field in the different spectral regimes accessed by each instrument. Evidence of wave dissipation is seen, and varies strongly with season. Observed GWPE for individual wave packets exhibits a log-normal distribution, with short-timescale intermittency dominating over a well-repeated monthly-median seasonal cycle. GWPE and λz exhibit strong correlations with the stratospheric winds, but not with local surface winds. Our results provide guidance for interpretation and intercomparison of such data sets in their full context.

scholarly journals Tomographic reconstruction of atmospheric gravity wave parameters from airglow observations

2017 ◽  
Author(s):  
Rui Song ◽  
Martin Kaufmann ◽  
Jörn Ungermann ◽  
Manfred Ern ◽  
Guang Liu ◽  
...  
Keyword(s):  
Gravity Wave ◽  
Tomographic Reconstruction ◽  
Lower Thermosphere ◽  
Real Data ◽  
Atmospheric Gravity Wave ◽  
Mesopause Region ◽  
Angle Measurements ◽  
Target Mode ◽  
Observation Strategy ◽  
Atmospheric Gravity

Abstract. Gravity waves (GWs) play an important role in atmospheric dynamics. Especially in the mesosphere and lower thermosphere (MLT) dissipating GWs provide a major contribution to the driving of the global wind system. Therefore global observations of GWs in the MLT region are of particular interest. The small scales of GWs, however, pose a major problem for the observation of GWs from space. We propose a new observation strategy for GWs in the mesopause region by combining limb and sub-limb satellite-borne remote sensing measurements for improving the spatial resolution of temperatures that are retrieved from atmospheric soundings. In our study, we simulate satellite observations of the rotational structure of the O2 A-band nightglow. A key element of the new method is the ability of the instrument or the satellite to operate in so called target mode, i.e. to stare at a particular point in the atmosphere and collect radiances at different viewing angles. These multi-angle measurements of a selected region allow for tomographic reconstruction of a 2-dimensional atmospheric state, in particular of gravity wave structures. As no real data is available, the feasibility of this tomographic retrieval is carried out with simulation data in this work. It shows that one major advantage of this observation strategy is that much smaller scale GWs can be observed. We derive a GW sensitivity function, and it is shown that target mode observations are able to capture GWs with horizontal wavelengths as short as ~ 50 km for a large range of vertical wavelengths. This is far better than the horizontal wavelength limit of 100–200 km obtained for conventional limb sounding.

Infrasound scattering from stochastic gravity wave packets

2017 ◽  
Vol 141 (5) ◽  
pp. 3628-3628
Author(s):  
Christophe MILLET ◽  
Bruno RIBSTEIN ◽  
Francois LOTT
Keyword(s):  
Gravity Wave ◽  
Wave Packets ◽  
Stochastic Gravity

scholarly journals Long-term lidar observations of the gravity wave activity near the mesopause at Arecibo

2019 ◽  
Vol 19 (5) ◽  
pp. 3207-3221
Author(s):  
Xianchang Yue ◽  
Jonathan S. Friedman ◽  
Qihou Zhou ◽  
Xiongbin Wu ◽  
Jens Lautenbach
Keyword(s):  
Gravity Wave ◽  
Lower Thermosphere ◽  
Strong Support ◽  
Temporal Correlation ◽  
Temperature Inversion ◽  
Dynamical Instability ◽  
Temperature Structure ◽  
Mesopause Region ◽  
Mean Temperature ◽  
Lidar Observations

Abstract. Using 11-year-long K Doppler lidar observations of temperature profiles in the mesosphere and lower thermosphere (MLT) between 85 and 100 km, conducted at the Arecibo Observatory, Puerto Rico (18.35∘ N, 66.75∘ W), seasonal variations of mean temperature, the squared Brunt–Väisälä frequency, N2, and the gravity wave potential energy (GWPE) are estimated in a composite year. The following unique features are obtained. (1) The mean temperature structure shows similar characteristics to an earlier report based on a smaller dataset. (2) Temperature inversion layers (TILs) occur at 94–96 km in spring, at ∼92 km in summer, and at ∼91 km in early autumn. (3) The first complete range-resolved climatology of GWPE derived from temperature data in the tropical MLT exhibits an altitude-dependent combination of annual oscillation (AO) and semiannual oscillation (SAO). The maximum occurs in spring and the minimum in summer, and a second maximum is in autumn and a second minimum in winter. (4) The GWPE per unit volume reduces below ∼97 km altitude in all seasons. The reduction of GWPE is significant at and below the TILs but becomes faint above; this provides strong support for the mechanism that the formation of upper mesospheric TILs is mainly due to the reduction of GWPE. The climatology of GWPE shows an indeed pronounced altitudinal and temporal correlation with the wind field in the tropical mesopause region published in the literature. This suggests the GW activity in the tropical mesopause region should be manifested mainly by the filtering effect of the critical level of the local background wind and the energy conversion due to local dynamical instability.

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