Many numerical models for weather prediction and climate studies are run at resolutions that are too coarse to resolve convection explicitly, but too fine to justify the local equilibrium assumed by conventional convective parametrizations. The Plant–Craig (PC) stochastic convective parametrization scheme, developed in this paper, solves this problem by removing the assumption that a given grid...

Using satellite cloud data from the Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) and collocated precipitation rates from the Advanced Microwave Scanning Radiometer (AMSR), it is shown that rain rate is closely related to the amount of very thick high cloud, which is a better proxy for precipitation than outgoing longwave radiation (OLR). It is also shown that thin high cloud, whic...

This paper investigates the impacts of horizontal resolution on the statistical behavior of convection. An idealized radiative–convective equilibrium is simulated for model resolutions ranging between 2 and 50 km. The simulations are compared based upon the analysis of the mean state, the energy and water vapor transport, and the probability distribution functions for various quantities. It is ...

Rotating radiative–convective equilibrium, using the column physics and resolution of GCMs, is proposed as a useful framework for studying the tropical storm–like vortices produced by global models. These equilibria are illustrated using the column physics and dynamics of a version of the GFDL Atmospheric Model 2 (AM2) at resolutions of 220, 110, and 55 km in a large 2 10 km square horizontally...

AB S TRACT Large-scale magnetic ®elds are believed to play an important role in the radiative zone of the Sun, in particular in the dynamical processes in the transition region between the convective and radiative zones (the tachocline). Also, they are probably responsible for the observed uniform rotation of the radiative zone. In that respect, since it has been suggested that the solar dynamo...

The simulation of nonlinear ultrasound propagation through tissue realistic media has a wide range of practical applications. However, this is a computationally difficult problem due to the large size of the computational domain compared to the acoustic wavelength. Here, the k-space pseudospectral method is used to reduce the number of grid points required per wavelength for accurate simulation...

With the help of new recent stellar models, we have studied the distribution in the HR diagram of 2170 stars from the Hipparcos database, subdivided into diierent groups according to their total velocities with respect to the local Keplerian reference frame and into diierent groups of metallicity. We discuss the morphology of the main sequence at the boundary between radiative and convective st...

Whereas penumbral models during the last 15 years have been successful in explaining Evershed flows and magnetic field inclination variations in terms of flux tubes, the lack of contact between these models and a convective process needed to explain the penumbral radiative heat flux has been disturbing. We report on recent observational and theoretical evidence that challenge flux tube interpre...