Advection of Passive Tracers in the Atmosphere: Batchelor Scaling

Dynamics of passive tracers in the atmosphere: laboratory experiments and numerical tests with reanalysis wind fields.

Laboratory and numerical experiments are reported on dye advection processes in geostrophic turbulence. The experimental setup is the classical rotating annulus with differential heating which mimics the most essential features of midlatitude atmospheric flow. The main control parameter is the temperature contrast. Fluorescent dye is used as passive tracer, and dispersion is evaluated by digita...

Anomalous scaling for a passive scalar near the Batchelor limit

A class of phenomenological Hopf equations describing mixing of a passive scalar by random flow close to the Batchelor limit ~i.e., advection by random strain and vorticity! is analyzed. In the Batchelor limit multipoint correlators of the scalar are constructed explicitly by exploiting the SL (N ,R) symmetry of the Hopf operator. Hopf equations close to this ‘‘integrable’’ limit are solved via...

Local and nonlocal advection of a passive scalar

Passive and active scalar mixing is examined in a simple one-parameter family of two-dimensional flows based on quasi-geostrophic dynamics, in which the active scalar, the quasi-geostrophic potential vorticity, is confined to a single horizontal surface so-called surface quasi-geostrophic dynamics and in which a passive scalar field is also advected by the horizontal, two-dimensional velocity f...

The Analysis of Monthly moisture advection changes in Iran’s atmosphere over the recent half-century

Chaotic advection and relative dispersion in an experimental convective flow

Lagrangian motion in a quasi-two-dimensional, time-dependent, convective flow is studied at different Rayleigh numbers. The particle tracking velocimetry technique is used to reconstruct Lagrangian trajectories of passive tracers. Dispersion properties are investigated by means of the recently introduced finite size Lyapunov exponent analysis. Lagrangian motion is found to be chaotic with a Lya...