The depth of the planetary boundary layer (PBL) is a climatologically important quantity that has received little attention on regional to global scales. Here a 10-yr climatology of PBL depth from the University of California, Los Angeles (UCLA) atmospheric GCM is analyzed using the PBL mass budget. Based on the dominant physical processes, several PBL regimes are identified. These regimes tend...

Effect of rotation on nonlinear solutal convection during protein cystallization is modelled and studied computationally under both normal and microgravity conditions. The axis of the externally imposed rotation, which is assumed to be either parallel or antiparallel to the gravity vector, is assumed to be inclined at an angle γ with respect to the axis of the crystal. In addition to the angle ...

Direct numerical simulations of the time evolution of homogeneous stably stratified shear flows have been performed for mean flow Richardson numbers in the range from 0.075 to 1.00 and for Prandtl numbers ranging from 0.1 to 2. The local or instantaneous results indicate that when the turbulent Froude number FrT = 1 the peak value of mixing efficiency is Rf ≈ 0.25, a result independent of the P...

Internal gravity waves excited by the turbulent motions in a bottom Ekman layer are examined using large-eddy simulation. The outer flow is steady and uniformly stratified while the density gradient is set to zero at the flat lower wall. After initializing with a linear density profile, a mixed layer forms near the wall separated from the ambient stratification by a pycnocline. Two types of int...

[1] Internal solitons generated at the Columbia River plume front during ebb tide are displayed on a synthetic aperture radar (SAR) image taken on 26 July 2004 at 14:24:22 UTC. Scale analyses suggest that these internal solitons belong to the finite-depth category. A theoretical model, relating the radar backscatter cross section to dynamic parameters of internal solitons in the continuous stra...

A unique approach to simulate mass transfer across the moving droplet where mass transport equations and governing equations of the levels set method are solved separately is proposed in this work. Mass transfer coefficients of the chemical species can be computed by equating the diffusive flux and the mass transfer flux at the interface, which are found to be of the same order of magnitude as ...

[1] The evolution of bubbles in a turbulent oceanic boundary layer is simulated using a multi-size multi-gas bubble model coupled with a Large Eddy Simulation model. Bubbles injected by breaking waves are brought into the boundary layer by episodic bubble plumes, and they form near-surface streaks in the convergence zone of Langmuir circulations. The equilibrium bubble distribution decays expon...

Abstract The magnitude of the entrainment buoyancy flux, and hence growth rate convective boundary layer, does not increase monotonically with wind shear. Explanations for this have previously been based on wind-shear effects turbulence kinetic energy. By distinguishing between turbulent non-turbulent regions, we provide an alternative explanation two competing effects: initial decrease in corr...