Journal of the Atmospheric Sciences: Recent submissions
Now showing items 4721-4740 of 13215
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Forecast Skill of Targeted Observations: A Singular-Vector-Based Diagnostic
(American Meteorological Society, 2003)Targeted dropsonde data have been assimilated using the operational ECMWF four-dimensional variational data assimilation (4DVAR) system for 10 cases of the North Pacific Experiment (NORPEX) campaign, and their impact on ... -
Generation Mechanisms of Convectively Forced Internal Gravity Waves and Their Propagation to the Stratosphere
(American Meteorological Society, 2003)Characteristics of gravity waves induced by mesoscale convective storms and the gravity wave sources are investigated using a two-dimensional cloud-resolving numerical model. In a nonlinear moist (control) simulation, the ... -
The Nonlinear Interaction of Barotropic and Equatorial Baroclinic Rossby Waves
(American Meteorological Society, 2003)Simplified asymptotic equations are developed for the nonlinear interaction of long-wavelength equatorial Rossby waves and barotropic Rossby waves with a significant midlatitude projection in the presence of suitable ... -
Convective Impact on Temperatures Observed near the Tropical Tropopause
(American Meteorological Society, 2003)Observed temperature trends and interannual variations near the tropical tropopause suggest that temperatures up to the cold point are controlled by the troposphere, but some models indicate otherwise. Here, previous ... -
Vapor Pressure Measurement of Supercooled Water
(American Meteorological Society, 2003)A new dewpoint hygrometer was developed for subfreezing temperature application. Vapor pressure of supercooled water was determined by measuring temperatures at the dew-forming surface and the vapor source ice under the ... -
The Dynamics Associated with Equatorial Atmospheric Angular Momentum in an Aquaplanet GCM
(American Meteorological Society, 2003)The dynamical processes that drive intraseasonal equatorial atmospheric angular momentum (EAAM) fluctuations in a 4000-day aquaplanet GCM run are examined. The all-ocean lower boundary has a sea surface temperature field ... -
Monte Carlo Simulation of Solar Reflectances for Cloudy Atmospheres
(American Meteorological Society, 2003)Monte Carlo simulations of solar radiative transfer were performed for a well-resolved, large, three-dimensional (3D) domain of boundary layer cloud simulated by a cloud-resolving model. In order to represent 3D distributions ... -
A New Hypothesis for the Mechanism of Ice Nucleation on Wetted AgI and AgI·AgCl Particulate Aerosols
(American Meteorological Society, 2003)A potential molecular mechanism of ice nucleation on AgI and AgI?·?AgCl particulates involves rearrangement of ordered water molecule clusters associated with hydrated Ag+ ion patches. This nucleation mechanism is thought ... -
Large-Scale Flow Response to Short Gravity Waves Breaking in a Rotating Shear Flow
(American Meteorological Society, 2003)A two-dimensional rotating anelastic model is used to analyze the large-scale flow (LSF) response to the breaking of gravity waves (GWs) at critical levels. In the response the balanced part is separated from the inertial ... -
The Observed Structure of Convectively Coupled Kelvin Waves: Comparison with Simple Models of Coupled Wave Instability
(American Meteorological Society, 2003)Observations of the horizontal and vertical structure of convectively coupled Kelvin waves are presented and are compared with the predicted structures of moist Kelvin (or gravity) waves in three simple models of coupled ... -
Convection and Easterly Wave Structures Observed in the Eastern Pacific Warm Pool during EPIC-2001
(American Meteorological Society, 2003)During September?October 2001, the East Pacific Investigation of Climate Processes in the Coupled Ocean?Atmosphere System (EPIC-2001) intertropical convergence zone (ITCZ) field campaign focused on studies of deep convection ... -
Roundness and Aspect Ratio of Particles in Ice Clouds
(American Meteorological Society, 2003)The frequency of occurrence of the aspect ratio and roundness of particles in ice clouds from aircraft observations have been examined. Images of cloud particles were measured by a cloud particle imager (CPI) at 2.3-?m ... -
The Dynamical Relationship between Subtropical and Eddy-Driven Jets
(American Meteorological Society, 2003)This study examines the impact of a subtropical jet on the development of baroclinic waves and polar-front jets with an idealized multilevel primitive equation model. Linear stability analysis and initial-value approaches ... -
The k−3 and k−5/3 Energy Spectrum of Atmospheric Turbulence: Quasigeostrophic Two-Level Model Simulation
(American Meteorological Society, 2003)The Nastrom?Gage energy spectrum of atmospheric turbulence as a function of wavelength is simulated here with a two-level quasigeostrophic (QG) model. This simple model has no topography, no direct wave forcing, and no ... -
A Comparison of Breeding and Ensemble Transform Kalman Filter Ensemble Forecast Schemes
(American Meteorological Society, 2003)The ensemble transform Kalman filter (ETKF) ensemble forecast scheme is introduced and compared with both a simple and a masked breeding scheme. Instead of directly multiplying each forecast perturbation with a constant ... -
On the Seasonality of the Hadley Cell
(American Meteorological Society, 2003)The annual march of the climatological mean meridional circulations (MMCs) in the NCEP?NCAR reanalyses is dominated by two components of roughly comparable mean-squared amplitude: 1) a seasonally invariant pair of ?Hadley ... -
Effects of Moist Convection on Mesoscale Predictability
(American Meteorological Society, 2003)In a previous study by the authors, it was shown that the problematic numerical prediction of the 24?25 January 2000 snowstorm along the east coast of the United States was in some measure due to rapid error growth at ... -
A Similarity Hypothesis for Air–Sea Exchange at Extreme Wind Speeds
(American Meteorological Society, 2003)Hurricane intensity is sensitive to fluxes of enthalpy and momentum between the ocean and atmosphere in the high wind core of the storm. It has come to be recognized that much of this exchange is likely mediated by sea ... -
Resolved Scales and Nonlinear Interactions in Limited-Area Models
(American Meteorological Society, 2003)A procedure for identifying the resolved scales in nested limited-area models (LAMs) and for computing the nonlinear interactions between these scales is sketched in this paper. The spectral perspective is adopted and ... -
Parameterizing Ice Cloud Inhomogeneity and the Overlap of Inhomogeneities Using Cloud Radar Data
(American Meteorological Society, 2003)Cloud variability on scales smaller than the gridbox size of numerical forecast and climate models is believed to be important in determining the radiative effects of clouds, and increasingly attempts are being made to ...