Measurements of turbulent fluctuations of horizontal and vertical components of velocity, salinity and suspended particulate matter are presented. Turbulent Prandtl numbers are found to increase with stratification and to become larger than 1. Consequently, the vertical turbulent mass transport is suppressed by buoyancy forces, before the turbulent kinetic energy (TKE) and vertical turbulent mo...

Transient laminar mixed convection in an asymmetrically and differentially heated vertical channel of finite length subject to an opposing buoyancy is investigated by solving the unsteady two-dimensional Navier–Stokes and energy equations. Results illustrate the effects of buoyancy strength or Richardson number Ri 1⁄4 Gr=Re and Reynolds number Re on the overall flow structure and the nondimensi...

The available data, mainly topography, geoid, and heat flow, describing hotspots worldwide are examined to constrain the mechanisms for swell uplift and to obtain fluxes and excess temperatures of mantle plumes. Swell uplift is caused mainly by excess temperatures that move with the lithosphere plate and to a lesser extent hot asthenosphere near the hotspot. The volume, heat, and buoyancy fluxe...

1463-5003/$ see front matter 2009 Elsevier Ltd. A doi:10.1016/j.ocemod.2009.06.014 * Corresponding author. Address: Climate and National Center for Atmospheric Research, Boulder, C 303 497 17 21. E-mail address: [email protected] (S.G. Yeager). The sensitivity of the North Atlantic gyre circulation to high latitude buoyancy forcing is explored in a global, non-eddy resolving ocean general circula...

A series of dye releases in the Hudson River estuary elucidated diapycnal mixing rates and temporal variability over tidal and fortnightly time scales. Dye was injected in the bottom boundary layer for each of four releases during different phases of the tide and of the spring–neap cycle. Diapycnal mixing occurs primarily through entrainment that is driven by shear production in the bottom boun...

We derive an analytic model for nonlinear “photon bubble” wave trains driven by buoyancy forces in magnetized, radiation pressure-dominated atmospheres. Continuous, periodic wave solutions exist when radiative diffusion is slow compared to the dynamical timescale of the atmosphere. We identify these waves with the saturation of a linear instability discovered by Arons — therefore, these wave tr...

Mixed-layer budgets of boundary layer mass, moisture, and liquid water static energy are estimated from 6 days of data collected at 20°S, 85°W (a region of persistent stratocumulus) during the East Pacific Investigation of Climate (EPIC) stratocumulus cruise in 2001. These budgets are used to estimate a mean diurnal cycle of entrainment and, by diagnosing the fluxes of humidity and liquid water...

Satellite altimetric observations of the ocean reveal surface pressure patterns in the core of the Antarctic Circumpolar Current (ACC) that propagate downstream (eastward) but slower than the mean surface current by about 25%. We argue that these observations are suggestive of baroclinically unstable waves that have a steering level at a depth of about 1 km. Detailed linear stability calculatio...

Direct numerical simulations of an Ekman layer are performed to study flow evolution during the response of an initially neutral boundary layer to stable stratification. The Obukhov length, L , is varied among cases by imposing a range of stable buoyancy fluxes at the surface to mimic ground cooling. The imposition of constant surface buoyancy flux , i.e. constant-flux stability, leads to a buo...

The interaction of thermal radiation with conduction and laminar natural convection in a vertical circular pin, situated at participating gas, is numerically investigated. An absorbing and emitting gas is considered, and treated to be a gray participating media. Under the idealizing of gray gas, the Rosselan4 approximation is employed to describe the radiative heat flux in the energy equation. ...