Journal of the Atmospheric Sciences: Recent submissions
Now showing items 4781-4800 of 13215
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Regime Transitions and Heteroclinic Connections in a Barotropic Atmosphere
(American Meteorological Society, 2003)By interpreting transitions between atmospheric flow regimes as a deterministic rather than a stochastic phenomenon, new insight is gained into the phase-space characteristics of these transitions. The identification of ... -
A Nonlinear Theory for El Niño Bursting
(American Meteorological Society, 2003)A new mechanism is proposed that explains two key features of the observed El Niño?Southern Oscillation (ENSO) phenomenon?its irregularity and decadal amplitude changes. Using a low-order ENSO model, the authors show that ... -
Mesoscale Variations of Tropospheric Aerosols
(American Meteorological Society, 2003)Tropospheric aerosols are calculated to cause global-scale changes in the earth's heat balance, but these forcings are space/time integrals over highly variable quantities. Accurate quantification of these forcings will ... -
Instability of 2D Flows to Hydrostatic 3D Perturbations
(American Meteorological Society, 2003)Considered here is the evolution of three-dimensional perturbations to the hydrostatic equations linearized about a two-dimensional base state U. Motivated by an argument by T. Warn, this study begins with the nonrotating, ... -
Climatological Effects of Orography and Land–Sea Heating Contrasts on the Gravity Wave–Driven Circulation of the Mesosphere
(American Meteorological Society, 2003)On the basis of permanent January simulations performed with an idealized general circulation model for the troposphere and middle atmosphere, the sensibility of the general circulation to orographic and thermal forcing ... -
Mass-Flux Budgets of Shallow Cumulus Clouds
(American Meteorological Society, 2003)The vertical transport by shallow nonprecipitating cumulus clouds of conserved variables, such as the total specific humidity or the liquid water potential temperature, can be well modeled by the mass-flux approach, in ... -
Moist Component Potential Vorticity
(American Meteorological Society, 2003)The role that atmospheric water, in both its liquid and vapor phases, plays in cyclogenesis is difficult to determine because of the complex interactions between dynamic and thermodynamic forcings. From a potential vorticity ... -
A Shallow-Convection Parameterization for Mesoscale Models. Part I: Submodel Description and Preliminary Applications
(American Meteorological Society, 2003)A shallow-convection parameterization suitable for both marine and continental regimes is developed for use in mesoscale models. The scheme is closely associated with boundary layer turbulence processes and can transition ... -
Linear and Nonlinear Propagation of Supercell Storms
(American Meteorological Society, 2002)A nonlinear formula for updraft motion in supercell storms is derived from Petterssen's formula for the motion of systems and the vertical equation of motion, and tested on form-preserving disturbances. At each level, ... -
The Anatomy of a Continental Tropical Convective Storm
(American Meteorological Society, 2003)This study provides a very clear picture of the microphysics and flow field in a convective storm in the Rondonia region of Brazil through a synthesis of observations from two unique radars, measurements of the surface ... -
A Missing Solution to the Transport Equation and Its Effect on Estimation of Cloud Absorptive Properties
(American Meteorological Society, 2002)Most of the existing cloud radiation models treat liquid water drops of a variety of sizes as an ensemble of particles. The ensemble approach assumes that all drop sizes are well represented in an elementary volume, and ... -
A Shallow-Convection Parameterization for Mesoscale Models. Part II: Verification and Sensitivity Studies
(American Meteorological Society, 2003)Formulations describing a new shallow-convection parameterization intended for mesoscale models have been described in a companion paper, Part I. In the present paper the convection scheme is tested and evaluated against ... -
A PDF-Based Model for Boundary Layer Clouds. Part II: Model Results
(American Meteorological Society, 2002)A new single-column model for the cloudy boundary layer, described in a companion paper, is tested for a variety of regimes. To represent the subgrid-scale variability, the model uses a joint probability density function ... -
Shear-Flow Instability in the Stable Nocturnal Boundary Layer as Observed by Doppler Lidar during CASES-99
(American Meteorological Society, 2003)This study investigates a shear-flow instability observed in the stably stratified nighttime boundary layer on 6 October 1999 during the Cooperative Atmosphere?Surface Exchange Study (CASES-99) in south-central Kansas. A ... -
Observations and Parameterizations of Particle Size Distributions in Deep Tropical Cirrus and Stratiform Precipitating Clouds: Results from In Situ Observations in TRMM Field Campaigns
(American Meteorological Society, 2002)This study reports on the evolution of particle size distributions (PSDs) and habits as measured during slow, Lagrangian-type spiral descents through deep subtropical and tropical cloud layers in Florida, Brazil, and ... -
A Study of the Response of Deep Tropical Clouds to Large-Scale Thermodynamic Forcings. Part I: Modeling Strategies and Simulations of TOGA COARE Convective Systems
(American Meteorological Society, 2002)Interactions between deep tropical clouds over the western Pacific warm pool and the larger-scale environment are key to understanding climate change. Cloud models are an extremely useful tool in simulating and providing ... -
Variational Objective Analysis for Atmospheric Field Programs: A Model Assessment
(American Meteorological Society, 2002)The objective of this study is to examine the effectiveness of the variational objective analysis (VOA) for producing realistic diagnoses of atmospheric field program data. Simulations from the Naval Research Laboratory's ... -
A PDF-Based Model for Boundary Layer Clouds. Part I: Method and Model Description
(American Meteorological Society, 2002)A new cloudy boundary layer single-column model is presented. It is designed to be flexible enough to represent a variety of cloudiness regimes?such as cumulus, stratocumulus, and clear regimes?without the need for ... -
Microscopic Approach to Cloud Droplet Growth by Condensation. Part II: Turbulence, Clustering, and Condensational Growth
(American Meteorological Society, 2002)The goal of this work is to answer the question of whether nonuniformity in the spatial distribution of sizes and positions of cloud droplets and/or variable vertical velocity in a turbulent medium can contribute to the ... -
Small-Scale and Mesoscale Variability in Cloudy Boundary Layers: Joint Probability Density Functions
(American Meteorological Society, 2002)The joint probability density function (PDF) of vertical velocity and conserved scalars is important for at least two reasons. First, the shape of the joint PDF determines the buoyancy flux in partly cloudy layers. Second, ...