Cyclone-anticyclone asymmetry and alignment statistics in homogeneous rotating turbulence

Anisotropy and cyclone-anticyclone asymmetry in decaying rotating turbulence

The effect of a background rotation on the decay of homogeneous turbulence produced by a grid is experimentally investigated. Experiments have been performed in a channel mounted in the large-scale ’Coriolis’ rotating platform, and measurements have been carried out in the planes normal and parallel to the rotation axis using particle image velocimetry. After a short period of about 0.4 tank ro...

Cyclone-anticyclone asymmetry of large-scale wakes in the laboratory

We performed an experimental study of large-scale wakes in a rotating shallow-water layer. Standard particle image velocimetry was used to measure the horizontal velocity field, while a laser-induced fluorescence technique was used to measure the geopotential deviation i.e., the interface deviation . According to these measurements, we were able to quantify the dynamics in a wide region of para...

The coherent structures of shallow-water turbulence: Deformation-radius effects, cyclone/anticyclone asymmetry and gravity-wave generation.

Over a large range of Rossby and Froude numbers, we investigate the dynamics of initially balanced decaying turbulence in a shallow rotating fluid layer. As in the case of incompressible two-dimensional decaying turbulence, coherent vortex structures spontaneously emerge from the initially random flow. However, owing to the presence of a free surface, a wealth of new phenomena appear in the sha...

The true asymmetry between synoptic cyclone and anticyclone amplitudes: Implications for filtering methods in Lagrangian feature tracking

Statistics of turbulence via polarimetry: alignment of grains and atoms

Most astrophysical fluids are turbulent and magnetized. Fluctuations of polarization provide a promising way to study astrophysical magnetic turbulence. We discuss polarization that arises from grains and atoms aligned in respect to magnetic field, describe the processes of alignment, explain when the alignment reflects the direction of magnetic field. We show that temporal fluctuations of inte...