Convective Downmixing of Plumes in a Coastal Environment

Transitions in convective turbulence: The role of thermal plumes.

Experiments on convective turbulence have revealed a number of unexpected changes in measured signals. Most notable are (i) the transition from "soft" to "hard" turbulence at Rayleigh number (Ra) of about 10, which is seen as a qualitative change in the statistics of temperature Auctuations; (ii) a transition at Ra of about 10",seen in the power spectra of temperature fluctuations measured at t...

Do undiluted convective plumes exist in the upper tropical troposphere?

Using a passive tracer, entrainment is studied in cloud-resolving simulations of oceanic deep convection in radiative-convective equilibrium. It is found that the convective flux of undiluted parcels decays with height exponentially, indicating a constant probability per vertical distance of mixing with environmental air. This probability per distance is sufficiently large that undiluted updraf...

Convective plumes and the scarcity of Titan’s clouds

[1] We show that simple thermodynamic models of convective plumes predict the area fraction of convective plumes (i.e., updrafts) in Titan’s atmosphere to be 12 smaller than on Earth. This result is in agreement with predictions by sophisticated dynamical models and with the relative tropospheric cloud cover, which is only 1% on Titan. Rainstorms on Titan, being so rare, may be violent. Citatio...

Eulerian mean flow from an instability of convective plumes.

The dynamical origin of large-scale flows in systems driven by concentrated Archimedean forces is considered. A two-dimensional model of plumes, such as those observed in thermal convection at large Rayleigh and Prandtl numbers, is introduced. From this model, we deduce the onset of mean flow as an instability of a convective state consisting of parallel vertical flow supported by buoyancy forc...

Deep mantle plumes and convective upwelling beneath the Pacific Ocean