Journal of the Atmospheric Sciences: Recent submissions

Now showing items 3721-3740 of 13215

    • Impacts of Convective Lifetime on Moist Geostrophic Adjustment 

      Dias, Juliana; Pauluis, Olivier (American Meteorological Society, 2010)
      This paper presents a theoretical study of the effects of moist convection on geostrophic adjustment in an infinite channel. The governing equations correspond to a linearized shallow water system of equations for the ...

    • Contrails of Small and Very Large Optical Depth 

      Atlas, David; Wang, Zhien (American Meteorological Society, 2010)
      This work deals with two kinds of contrails. The first comprises a large number of optically thin contrails near the tropopause. They are mapped geographically using a lidar to obtain their height and a camera to obtain ...

    • Snow Studies. Part II: Average Relationship between Mass of Snowflakes and Their Terminal Fall Velocity 

      Szyrmer, Wanda; Zawadzki, Isztar (American Meteorological Society, 2010)
      This study uses a dataset of low-density snow aggregates measurements collected by a ground-based optical disdrometer that provides particle size and terminal fall speed for each size interval from which the velocity?size ...

    • Estimation of Dissipative Heating Using Low-Level In Situ Aircraft Observations in the Hurricane Boundary Layer 

      Zhang, Jun A. (American Meteorological Society, 2010)
      Data collected in the low-level atmospheric boundary layer in five hurricanes by NOAA research aircraft are analyzed to measure turbulence with scales small enough to retrieve the rate of dissipation. A total of 49 flux ...

    • Baroclinic Eddy Equilibration under Specified Seasonal Forcing 

      Zhang, Yang; Stone, Peter H. (American Meteorological Society, 2010)
      Baroclinic eddy equilibration under a Northern Hemisphere?like seasonal forcing is studied using a modified multilayer quasigeostrophic channel model to investigate the widely used ?quick baroclinic eddy equilibration? ...

    • MJO Signals in Latent Heating: Results from TRMM Retrievals 

      Zhang, Chidong; Ling, Jian; Hagos, Samson; Tao, Wei-Kuo; Lang, Steve; Takayabu, Yukari N.; Shige, Shoichi; Katsumata, Masaki; Olson, William S.; L’Ecuyer, Tristan (American Meteorological Society, 2010)
      Four Tropical Rainfall Measuring Mission (TRMM) datasets of latent heating were diagnosed for signals in the Madden?Julian oscillation (MJO). In all four datasets, vertical structures of latent heating are dominated by two ...

    • Attributing Tropical Cyclogenesis to Equatorial Waves in the Western North Pacific 

      Schreck, Carl J.; Molinari, John; Mohr, Karen I. (American Meteorological Society, 2010)
      Tropical cyclogenesis is attributed to an equatorial wave when the filtered rainfall anomaly exceeds a threshold value at the genesis location. It is argued that 0 mm day?1 (simply requiring a positive anomaly) is too small ...

    • Equatorial Mountain Torques and Cold Surge Preconditioning 

      Mailler, Sylvain; Lott, François (American Meteorological Society, 2010)
      The evolution of the two components of the equatorial mountain torque (EMT) applied by mountains on the atmosphere is analyzed in the NCEP reanalysis. A strong lagged relationship between the EMT component along the Greenwich ...

    • Observation and Theory of the Diurnal Continental Thermal Tide 

      Li, Yanping; Smith, Ronald B. (American Meteorological Society, 2010)
      Harmonic analysis of summer Automated Surface Observing System (ASOS) data over North America shows sun-following diurnal temperature and pressure oscillations with amplitudes increasing in the western United States (i.e., ...

    • Dynamical Feedbacks of the Southern Annular Mode in Winter and Summer 

      Barnes, Elizabeth A.; Hartmann, Dennis L. (American Meteorological Society, 2010)
      The persistence of the southern annular mode (SAM) is studied during austral winter (June?September) and summer (December?March) using observations of the three-dimensional vorticity budget. Analysis of the relative vorticity ...

    • Large-Eddy Observation of Post-Cold-Frontal Continental Stratocumulus 

      Mechem, David B.; Kogan, Yefim L.; Schultz, David M. (American Meteorological Society, 2010)
      More studies on the dynamics of marine stratus and stratocumulus clouds have been performed than comparable studies on continental stratocumulus. Therefore, to increase the number of observations of continental stratocumulus ...

    • Sensitivity of Tropical Cyclone Inner-Core Size and Intensity to the Radial Distribution of Surface Entropy Flux 

      Xu, Jing; Wang, Yuqing (American Meteorological Society, 2010)
      The surface energy (entropy) flux is critical to the development and maintenance of a tropical cyclone (TC). However, it is unclear how sensitive the inner-core size and intensity of a TC could be to the radial distribution ...

    • Advances in the Estimation of Ice Particle Fall Speeds Using Laboratory and Field Measurements 

      Heymsfield, A. J.; Westbrook, C. D. (American Meteorological Society, 2010)
      Accurate estimates for the fall speed of natural hydrometeors are vital if their evolution in clouds is to be understood quantitatively. In this study, laboratory measurements of the terminal velocity ?t for a variety of ...

    • Multiscale Models for Cumulus Cloud Dynamics 

      Stechmann, Samuel N.; Stevens, Bjorn (American Meteorological Society, 2010)
      Cumulus clouds involve processes on a vast range of scales?including cloud droplets, turbulent mixing, and updrafts and downdrafts?and it is often difficult to determine how processes on different scales interact with each ...

    • Momentum Fluxes of Gravity Waves Generated by Variable Froude Number Flow over Three-Dimensional Obstacles 

      Eckermann, Stephen D.; Lindeman, John; Broutman, Dave; Ma, Jun; Boybeyi, Zafer (American Meteorological Society, 2010)
      Fully nonlinear mesoscale model simulations are used to investigate the momentum fluxes of gravity waves that emerge at a ?far-field? height of 6 km from steady unsheared flow over both an axisymmetric and elliptical ...

    • Stratospheric Gravity Waves Generated by Typhoon Saomai (2006): Numerical Modeling in a Moving Frame Following the Typhoon 

      Kim, So-Young; Chun, Hye-Yeong (American Meteorological Society, 2010)
      Stratospheric gravity waves generated by Typhoon Saomai (2006) were simulated using a mesoscale model in a moving frame of reference following the typhoon. Waves with large amplitudes appear near the domain center because ...

    • Two- and Four-Stream Combination Approximations for Computation of Diffuse Actinic Fluxes 

      Zhang, Hua; Zhang, Feng; Fu, Qiang; Shen, Zhongping; Lu, Peng (American Meteorological Society, 2010)
      The δ-two- and four-stream combination approximations, which use a source function from the two-stream approximations and evaluate intensities in the four-stream directions, are formulated for the calculation of diffuse ...

    • Numerical Simulations of Low-CAPE Flows over a Mountain Ridge 

      Miglietta, Mario Marcello; Rotunno, Richard (American Meteorological Society, 2010)
      In a recent study, the authors performed numerical simulations of conditionally unstable flows past a mesoscale mountain ridge in order to investigate the statistically stationary features of the solution precipitation ...

    • A Direct Measure of Entrainment 

      Romps, David M. (American Meteorological Society, 2010)
      A method is introduced for directly measuring convective entrainment and detrainment in a cloud-resolving simulation. This technique is used to quantify the errors in the entrainment and detrainment estimates obtained using ...

    • Cellular Statistical Models of Broken Cloud Fields. Part II: Comparison with a Dynamical Model and Statistics of Diverse Ensembles 

      Alexandrov, Mikhail D.; Ackerman, Andrew S.; Marshak, Alexander (American Meteorological Society, 2010)
      Cellular statistical models are designed to provide a simple two-parameter characterization of the structure of broken cloud fields described through distributions of cloud fraction and of chord lengths for clouds and clear ...