Abstract: A series of 5-day forecasts for both winter and summer initial conditions have been performed using a fairly high resolution version (0.9375° latitude?longitude grid with 28 vertical levels) of a gridpoint semi-Lagrangian ...

Abstract: Two vertically discrete systems, one based on the ?Charney-Phillips grid? and the other on the ?Lorenz grid,? are compared in view of the quasi-geostrophic potential vorticity equation and baroclinic instability. It is ...

Abstract: We have investigated baroclinic instability with cumulus heating using a vertically discrete, linearized, quasi-geostrophic model on a ?-plane. Two formulations of cumulus heating were used. The first formulation (?-model) ...

Abstract: A simple implementation of the Arakawa and Schubert (1974) cumulus parameterization is presented. The major simplification made is to ?relax?the state toward equilibrium each time the parameterization is invoked, rather ...

Abstract: An efficient, direct, second-order solver for the discrete solution of a class of two-dimensional separable elliptic equations on the sphere (which generally arise in implicit and semi-implicit atmospheric models) is ...

Abstract: This study describes and demonstrates a new method for identifying deficiencies in how cloud processes are represented in large-scale models. Kilometer-scale-resolving cloud radar observations and cloud-resolving model ...

Abstract: General circulation model (GCM) simulations of low-frequency variability with time scales of 20 to 70 days are analyzed for the Pacific sector during boreal winter. The GCM's leading mode in the upper-tropospheric zonal ...

Abstract: The atmospheric response to a sea surface temperature anomaly over the equatorial eastern Pacific Ocean (SSTA) is investigated using the UCLA General Circulation Model. The SSTA used is an idealization of that compiled by ...

Abstract: This study evaluates the performance of the National Centers for Environmental Prediction Global Forecast System (GFS) against observations made by the U.S. Department of Energy Atmospheric Radiation Measurement (ARM) ...