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Articles 1 - 6 of 6
Full-Text Articles in Physical Sciences and Mathematics
Observations Of Reduced Turbulence And Wave Activity In The Arctic Middle Atmosphere Following The January 2015 Sudden Stratospheric Warming, Colin C. Triplett, Aroh Barjatya, Jintai Li, Richard L. Collins, Gerald A. Lehmacher, David C. Fritts, Boris Strelnikov, Franz-Josef Lübken, Brentha Thurairajah, V. Lynn Harvey, Donald L. Hampton, Roger H. Varney
Observations Of Reduced Turbulence And Wave Activity In The Arctic Middle Atmosphere Following The January 2015 Sudden Stratospheric Warming, Colin C. Triplett, Aroh Barjatya, Jintai Li, Richard L. Collins, Gerald A. Lehmacher, David C. Fritts, Boris Strelnikov, Franz-Josef Lübken, Brentha Thurairajah, V. Lynn Harvey, Donald L. Hampton, Roger H. Varney
Publications
Measurements of turbulence and waves were made as part of the Mesosphere-Lower Thermosphere Turbulence Experiment (MTeX) on the night of 25–26 January 2015 at Poker Flat Research Range, Chatanika, Alaska (65°N, 147°W). Rocket-borne ionization gauge measurements revealed turbulence in the 70- to 88-km altitude region with energy dissipation rates between 0.1 and 24 mW/kg with an average value of 2.6 mW/kg. The eddy diffusion coefficient varied between 0.3 and 134 m2/s with an average value of 10 m2/s. Turbulence was detected around mesospheric inversion layers (MILs) in both the topside and bottomside of the MILs. These …
Momentum Flux Spectra Of A Mountain Wave Event Over New Zealand, Katrina Bossert, David C. Fritts, Christopher J. Heale, Stephen D. Eckermann, John M. C. Plane, Jonathan B. Snively, Bifford P. Williams, Iain M. Reid, Damian J. Murphy, Andrew J. Spargo, Andrew D. Mackinnon
Momentum Flux Spectra Of A Mountain Wave Event Over New Zealand, Katrina Bossert, David C. Fritts, Christopher J. Heale, Stephen D. Eckermann, John M. C. Plane, Jonathan B. Snively, Bifford P. Williams, Iain M. Reid, Damian J. Murphy, Andrew J. Spargo, Andrew D. Mackinnon
Publications
During the Deep Propagating Gravity Wave Experiment (DEEPWAVE) 13 July 2014 research flight over the South Island of New Zealand, a multiscale spectrum of mountain waves (MWs) was observed. High-resolution measurements of sodium densities were available from ~70 to 100 km for the duration of this flight. A comprehensive technique is presented for obtaining temperature perturbations, T′, from sodium mixing ratios over a range of altitudes, and these T′ were used to calculate the momentum flux (MF) spectra with respect to horizontal wavelengths, λH, for each flight segment. Spectral analysis revealed MWs with spectral power centered at λH of ~80, …
Localization Effects On The Dissipation Of Gravity Wave Packets In The Upper Mesophere And Lower Thermosphere, C. J. Heale, R. L. Walterscheid, J. B. Snively
Localization Effects On The Dissipation Of Gravity Wave Packets In The Upper Mesophere And Lower Thermosphere, C. J. Heale, R. L. Walterscheid, J. B. Snively
Publications
Gravity waves not subject to breaking or filtering will dissipate due to viscosity and thermal conduction in the thermosphere. However, the evolutions of wave packets, and the altitudes they reach, are highly dependent upon the spectral content. In this paper, a 2‐D numerical model is used to investigate the effect of spatial localization (and thus spectral content) of a wave packet on its dissipation, dispersion, and spectral evolution. It is found that most wave packets launched below the thermosphere evolve to smaller central vertical wavelengths as the faster, longer vertical wavelength components reach the dissipative thermosphere and are removed first, …
A Comparison Of Small- And Medium-Scale Gravity Wave Interactions In The Linear And Nonlinear Limits, C. J. Heale, J. B. Snively
A Comparison Of Small- And Medium-Scale Gravity Wave Interactions In The Linear And Nonlinear Limits, C. J. Heale, J. B. Snively
Publications
A 2-D numerical model is used to compare interactions between small-scale (SS) (25 km horizontal wavelength, 10 min period) and medium-scale (MS, 250 km horizontal wavelength, 90 min period) gravity waves (GWs) in the Mesosphere and Lower Thermosphere within three different limits. First, the MS wave is specified as a static, horizontally homogeneous ambient atmospheric feature; second, a linear interaction is investigated between excited, time-dependent SS and MS waves, and third, a fully nonlinear interaction at finite amplitudes is considered. It is found that the finite-amplitude wave interactions can cause SS wave breaking aligned with the phase fronts of the …
First Search For Nontensorial Gravitational Waves From Known Pulsars, B. P. Abbott, K. Aultoneal, S. Gaudio, K. Gill, B. Hughey, J. W. W. Pratt, E. Schmidt, S. G. Schwalbe, M. J. Szczepańczyk, M. Zanolin, Et Al.
First Search For Nontensorial Gravitational Waves From Known Pulsars, B. P. Abbott, K. Aultoneal, S. Gaudio, K. Gill, B. Hughey, J. W. W. Pratt, E. Schmidt, S. G. Schwalbe, M. J. Szczepańczyk, M. Zanolin, Et Al.
Publications
We present results from the first directed search for nontensorial gravitational waves. While general relativity allows for tensorial (plus and cross) modes only, a generic metric theory may, in principle, predict waves with up to six different polarizations. This analysis is sensitive to continuous signals of scalar, vector, or tensor polarizations, and does not rely on any specific theory of gravity. After searching data from the first observation run of the advanced LIGO detectors for signals at twice the rotational frequency of 200 known pulsars, we find no evidence of gravitational waves of any polarization. We report the first upper …
Unexpected Occurrence Of Mesospheric Frontal Gravity Wave Events Over The South Pole (90 Degrees S), P.-D. Pautet, M. J. Taylor, J. B. Snively, C. Solorio
Unexpected Occurrence Of Mesospheric Frontal Gravity Wave Events Over The South Pole (90 Degrees S), P.-D. Pautet, M. J. Taylor, J. B. Snively, C. Solorio
Publications
Since 2010, Utah State University has operated an infrared Advanced Mesospheric Temperature Mapper at the Amundsen–Scott South Pole station to investigate the upper atmosphere dynamics and temperature deep within the vortex. A surprising number of “frontal” gravity wave events (86) were recorded in the mesospheric OH(3,1) band intensity and rotational temperature images (typical altitude of ~87 km) during four austral winters (2012–2015). These events are gravity waves (GWs) characterized by a sharp leading wave front followed by a quasi-monochromatic wave train that grows with time. A particular subset of frontal gravity wave events has been identified in the past (Dewan …