Recently added articles from Journal of the Atmospheric Sciences:
Factors Determining the Impact of Aerosols on Surface Precipitation from Clouds: An Attempt at Classification
Jun 01, 2008; Khain, A P; BenMoshe, N; Pokrovsky, A ... ABSTRACT The simulation of the dynamics and the microphysics of clouds observed during the Large-Scale Biosphere-Atmosphere Experiment in Amazonia-Smoke, Aerosols, Clouds, Rainfall, and Climate (LBASMOCC) campaign, as well as extremely continental and extremely maritime clouds, is ...
The Geometry of Model Error
Jun 01, 2008; Judd, Kevin; Reynolds, Carolyn A; Rosmond, Thomas E; Smith, Leonard A ... ABSTRACT This paper investigates the nature of model error in complex deterministic nonlinear systems such as weather forecasting models. Forecasting systems incorporate two components, a forecast model and a data assimilation method. The latter projects a collection of observations of ...
Sensitivity of a Large Ensemble of Tropical Convective Systems to Changes in the Thermodynamic and Dynamic Forcings
Jun 01, 2008; Eitzen, Zachary A; Xu, Kuan-Man ... ABSTRACT A two-dimensional cloud-resolving model (CRM) is used to perform five sets of simulations of 68 deep convective cloud objects identified with Clouds and the Earth's Radiant Energy System (CERES) data to examine their sensitivity to changes in thermodynamic and dynamic forcings ....
A Warm Rain Microphysics Parameterization that Includes the Effect of Turbulence
Jun 01, 2008; Franklin, Charmaine N ... ABSTRACT A warm rain parameterization has been developed by solving the stochastic collection equation with the use of turbulent collision kernels. The resulting parameterizations for the processes of autoconversion, accretion, and self-collection are functions of the turbulent intensity ...
Vertically Propagating Kelvin Waves and Tropical Tropopause Variability
Jun 01, 2008; Ryu, Jung-Hee; Lee, Sukyoung; Son, Seok-Woo ... ABSTRACT The relationship between local convection, vertically propagating Kelvin waves, and tropical tropopause height variability is examined. This study utilizes both simulations of a global primitive-equation model and global observational datasets. Regression analysis with the data ...
Dynamical Relationship between the Phase of North Atlantic Oscillations and the Meridional Excursion of a Preexisting Jet: An Analytical Study
Jun 01, 2008; Luo, Dehai; Gong, Tingting; Zhong, Linhao ... ABSTRACT In this paper, it is shown from an analytical solution that in the presence of a preexisting jet the interaction between the zonal jet and the topography of the land-sea contrast (LSC) in the Northern Hemisphere (NH) tends to induce a dipole component that depends crucially upon ...
A Theoretical and Numerical Study of Urban Heat Island-Induced Circulation and Convection
Jun 01, 2008; Han, Ji-Young; Baik, Jong-Jin ... ABSTRACT Urban heat island-induced circulation and convection in three dimensions are investigated theoretically and numerically in the context of the response of a stably stratified uniform flow to specified low-level heating that represents an urban heat island. In a linear, ...
Abrupt Seasonal Migration of the ITCZ into the Summer Hemisphere
Jun 01, 2008; Xian, Peng; Miller, Ron L ... ABSTRACT Although the maximum of solar radiation at the top of the atmosphere moves gradually from one hemisphere to the other as part of the seasonal cycle, the intertropical convergence zone (ITCZ) moves abruptly into the summer hemisphere. An axisymmetric circulation model is ...
Nonlinear Generalization of Singular Vectors: Behavior in a Baroclinic Unstable Flow
Jun 01, 2008; Rivière, Olivier; Lapeyre, Guillaume; Talagrand, Olivier ... ABSTRACT Singular vector (SV) analysis has proved to be helpful in understanding the linear instability properties of various types of flows. SVs are the perturbations with the largest amplification rate over a given time interval when linearizing the equations of a model along a ...
Mountain Waves in Two-Layer Sheared Flows: Critical-Level Effects, Wave Reflection, and Drag Enhancement
Jun 01, 2008; Teixeira, Miguel A C; Miranda, Pedro M A; Argaín, José L ... ABSTRACT Internal gravity waves generated in two-layer stratified shear flows over mountains are investigated here using linear theory and numerical simulations. The impact on the gravity wave drag of wind profiles with constant unidirectional or directional shear up to a certain height ...
On Simultaneous Data-Based Dimension Reduction and Hidden Phase Identification
Jun 01, 2008; Horenko, Illia ... ABSTRACT A problem of simultaneous dimension reduction and identification of hidden attractive manifolds in multidimensional data with noise is considered. The problem is approached in two consecutive steps: (i) embedding the original data in a sufficiently high-dimensional extended ...
Statistics of an Unstable Barotropic Jet from a Cumulant Expansion
Jun 01, 2008; Marston, J B; Conover, E; Schneider, Tapio ... ABSTRACT Low-order equal-time statistics of a barotropic flow on a rotating sphere are investigated. The flow is driven by linear relaxation toward an unstable zonal jet. For relatively short relaxation times, the flow is dominated by critical-layer waves. For sufficiently long ...
Small-Scale Moist Turbulence in Numerically Generated Convective Clouds
Jun 01, 2008; Spyksma, K; Bartello, P ... ABSTRACT The authors present simulations of cloud-free and cloudy, nonprecipitating, convective turbulence at spatial resolutions down to Δx = 2.6 m for a domain size of (1 km)^sup 3^. The runs are analyzed with attention focused on the dynamical differences between resolutions and ...
Shortwave Radiative Impacts from Aerosol Effects on Marine Shallow Cumuli
Jun 01, 2008; Zuidema, Paquita; Xue, Huiwen; Feingold, Graham ... ABSTRACT The net shortwave radiative impact of aerosol on simulations of two shallow marine cloud cases is investigated using a Monte Carlo radiative transfer model. For a shallow cumulus case, increased aerosol concentrations are associated not only with smaller droplet sizes but also ...
Modeling of the Melting Layer. Part IV: Brightband Bulk Parameterization
Jun 01, 2008; Heyraud, Catherine; Szyrmer, Wanda; Laroche, Stéphane; Zawadzki, Isztar ... ABSTRACT In this paper a simplified UHF-band backscattering parameterization for individual melting snowflakes is proposed. This parameterization is a function of the density, shape, and melted fraction, and is used here in a brightband bulk modeling study. A 1D bulk model is developed ...
Horizontally Homogeneous Rotating Radiative-Convective Equilibria at GCM Resolution
Jun 01, 2008; Held, Isaac M; Zhao, Ming ... ABSTRACT 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 ...
Piecewise Potential Vorticity Inversion: Elementary Tests
Jun 01, 2008; Egger, Joseph ... ABSTRACT Piecewise potential vorticity inversion (PPVI) is widely accepted as a useful tool in atmospheric diagnostics. This method is thought to quantify the instantaneous interaction at a distance of anomalies of potential vorticity (PV) separated horizontally and/or vertically. Doubts ...
Symmetric Stability of Compressible Zonal Flows on a Generalized Equatorial [beta] Plane
Jun 01, 2008; Fruman, Mark D; Shepherd, Theodore G ... ABSTRACT Sufficient conditions are derived for the linear stability with respect to zonally symmetric perturbations of a steady zonal solution to the nonhydrostatic compressible Euler equations on an equatorial β plane, including a leading order representation of the Coriolis force ...