Turbulent convection is often present in liquids with a kinematic viscosity much smaller than the diffusivity of the temperature. Here we reveal why these convection flows obey a much stronger level of fluid turbulence than those in which kinematic viscosity and thermal diffusivity are the same; i.e., the Prandtl number Pr is unity. We compare turbulent convection in air at Pr=0.7 and in liquid...

The hemispheric dichotomy on Mars is largely an expression of varying crustal thickness [1]. Although there is some disagreement as to the timing of its formation, the dichotomy is very old, forming during or before the early Noachian [2]. Several formation mechanisms, including both exogenic (giant impacts) [3] and endogenic processes including mantle convection [4], plate tectonics [5], and o...

LOWTO MODERATE-PRANDTL NUMBER FLUIDS Guy Metcalfe Division of Building, Construction and Engineering CSIRO Highett, Victoria AUSTRALIA R.P. Behringer Dept. of Physics and Center for Nonlinear and Complex Systems Duke University Durham, North Carolina USA to be given at the 12th Australasian Fluid Mechanics Conference, Sydney Australia December 10{15 1995 ABSTRACT Super uid mixtures have Prandtl...

A well-represented description of convection in weather and climate models is essential since convective clouds strongly influence the climate system. Convective processes interact with radiation, redistribute sensible and latent heat and momentum, and impact hydrological processes through precipitation. Depending on the models’ horizontal resolution, the representation of convection may look v...

[1] We seek to determine whether the adiabatic plasma transport and energization resulting from electric and magnetic drift can quantitatively account for the plasma sheet under weak and enhanced convection observed by Geotail presented in the companion paper [Wang et al., 2004]. We use a modified Magnetospheric Specification Model to simulate the dynamics and distributions of protons originati...

[1] The initial oceanic crust along volcanic passive margins is a factor of 3 greater than that of typical oceanic crust (20 versus 6–7 km). Convection driven by the edge of the continental lithosphere may cause mantle material to circulate through the shallow zone of significant melting beneath the nascent ocean basin and cause the volume of melted mantle to exceed that required to replace the...

We examine the large-scale ultraviolet aurora and convection responses to a series of flux transfer events that immediately followed a sharp and isolated southward turning of the IMF. During the interval of interest, SuperDARN was monitoring the plasma convection in the dayside northern ionosphere, while the VIS Earth Camera and the Far Ultraviolet Imager (UVI) were monitoring the northern hemi...

The floating zone (FZ) method is one of the growth techniques used to grow single crystal materials. FZ growth is achieved in a containerless environment (without a crucible) by the movement of a molten zone of a solid rod, which forms a free-standing liquid bridge between two solid sections. However, the surface tension along the free surface of the molten zone varies due to temperature and co...

Theoretical studies usually attribute convections to the developments of instabilities such as the static or symmetric instabilities of the basic flows. However, the following three facts make the validities of these basic theories unconvincing. First, it seems that in most cases the basic flow with balance property cannot exist as the exact solution, so one cannot formulate appropriate problem...

[1] Global high-resolution (3-hourly, 0.1 0.1 longitude-latitude) water vapor (6.7 mm) and window (11 mm) radiances from multiple geostationary satellites are used to document the diurnal cycle of upper tropospheric relative humidity (UTH) and its relationship to deep convection and high clouds in the whole tropics and to evaluate the ability of the new Geophysical Fluid Dynamics Laboratory (GF...