Apparent interactions between ducted gravity waves and pre-existing mesocyclones are investigated. Preliminary analyses of WSR-88D radar observations from several cases reveal that the intersection of fine lines, whose propagation speed is consistent with that of gravity waves, and existing mesocyclones leads to an increase in rotational velocity of the mesocyclone. Utilizing simplified ducted ...

In the present work we approximate an ultrarelativistic jet by a homogeneous beam of null matter with finite width. Then, we study the influence of this beam over the spacetime metric in the framework of higher-derivative gravity. We find an exact shock wave solution of the quadratic gravity field equations and compare it with the solution to Einstein’s gravity. We show that the effect of highe...

We report a laboratory investigation of weak turbulence of water surface waves in the gravity-capillary crossover. By using time-space-resolved profilometry and a bicoherence analysis, we observe that the nonlinear processes involve three-wave resonant interactions. By studying the solutions of the resonance conditions, we show that the nonlinear interaction is dominantly one dimensional and in...

A polar stratospheric ice cloud (PSC type II) was observed by airborne lidar above Greenland on 14 January 2000. It was the unique observation of an ice cloud over Greenland during the SOLVE/THESEO 2000 campaign. Mesoscale simulations with the hydrostatic HRM model are presented which, in contrast to global analyses, are capable to produce a vertically propagating gravity wave that induces the ...

We study the atmospheric structure in response to the propagation of gravity waves under nonisothermal (nonzero vertical temperature gradient), wind-shear (nonzero vertical zonal/meridional wind speed gradients), and dissipative (nonzero molecular viscosity and thermal conduction) conditions. As an alternative to the “complex wave-frequency” model proposed by Vadas and Fritts, we employ the tra...

A companion paper by Andreassen et M. (this issue) introduced and used a nonlinear, compressible, spectral collocation code to address the relative evolutions of two-dimensionM motions obtained in twoand three-dimensionM simulations of gravity wave breaking. That study illustrated the effects of instability on the wave field and mean flow evolution and suggested that two-dimensionM models are u...

We present an experimental study on gravity capillary wave turbulence in water. By using space-time resolved Fourier transform profilometry, the behavior of the wave energy density |η(k,ω)|(2) in the 3D (k,ω) space is inspected for various forcing frequency bandwidths and forcing amplitudes. Depending on the bandwidth, the gravity spectral slope is found to be either forcing dependent, as class...

We report the observation of changes in the wave turbulence properties of gravitycapillary surface waves due to a finite depth effect. When the fluid depth is decreased, a hump is observed on the wave spectrum in the capillary regime at a scale that depends on the depth. The possible origin of this hump is discussed. In the gravity regime, the wave spectrum still shows a power law but with an e...

Gravitational waves, although generally associated with extremely microscopic effects, can displace by hundreds of kilometers the pulsar interstellar scintillation patterns that bathe the Earth. The combination of the pulsar and the interstellar medium acts as a kiloparsec-long, nature-provided gravity wave amplifier. We show how an effective scheme for the detection of periodic gravity waves c...