Journal of the Atmospheric Sciences: Recent submissions

Now showing items 4701-4720 of 13215

    • Unsteady Thermally Driven Flows on Gentle Slopes 

      Hunt, J. C. R.; Fernando, H. J. S.; Princevac, M. (American Meteorological Society, 2003)
      The theoretical and laboratory studies on mean velocity and temperature fields of an unsteady atmospheric boundary layer on sloping surfaces reported here were motivated by recent field observations on thermally driven ...

    • Barotropic Instability and Equatorial Superrotation 

      Williams, G. P. (American Meteorological Society, 2003)
      Baroclinically unstable zones in midlatitudes normally produce medium-scale planetary waves that propagate toward the equator where they generate easterlies while transferring westerly momentum poleward, so that the jet ...

    • Flow in the Lee of Idealized Mountains and Greenland 

      Petersen, GuĐún Nína; Ólafsson, Haraldur; Kristjánsson, Jón Egill (American Meteorological Society, 2003)
      A series of idealized simulations of flow impinging on large mountains is conducted to investigate the impact of the mountain on the flow far downstream and to shed some light on the effects that Greenland may have on ...

    • Sensitivity of Intraseasonal Perturbations in SST to the Structure of the MJO 

      Zhang, Chidong; Anderson, Steven P. (American Meteorological Society, 2003)
      This study demonstrates that intraseasonal perturbations in sea surface temperature (SST?) in the western Pacific warm pool is very sensitive to the structure, as well as other characteristics, of the Madden?Julian oscillation ...

    • Reply 

      Schär, Christoph (American Meteorological Society, 2003)

    • A Theory for the Indian Ocean Dipole–Zonal Mode 

      Li, Tim; Wang, Bin; Chang, C-P.; Zhang, Yongsheng (American Meteorological Society, 2003)
      Four fundamental differences of air?sea interactions between the tropical Pacific and Indian Oceans are identified based on observational analyses and physical reasoning. The first difference is represented by the strong ...

    • Convective Forcing in the Intertropical Convergence Zone of the Eastern Pacific 

      Raymond, David J.; Raga, G. B.; Bretherton, Christopher S.; Molinari, John; López-Carrillo, Carlos; Fuchs, Željka (American Meteorological Society, 2003)
      One of the goals of the East Pacific Investigation of Climate, year 2001 process study (EPIC2001), was to understand the mechanisms controlling the forcing of deep atmospheric convection over the tropical eastern Pacific. ...

    • Comments on “A Generalization of Bernoulli's Theorem” 

      Davies-Jones, Robert (American Meteorological Society, 2003)

    • “Renormalization” Approach for Subgrid-Scale Representations 

      Yano, Jun-Ichi; Bechtold, Peter; Redelsperger, Jean-Luc (American Meteorological Society, 2003)
      Physical processes in numerical modeling are currently handled by a dichotomy of either an explicit or a parameterization approach. Herein, an alternative approach is proposed, in which degrading explicit physics with ...

    • Generalized Stability of Nongeostrophic Baroclinic Shear Flow. Part I: Large Richardson Number Regime 

      Heifetz, Eyal; Farrell, Brian F. (American Meteorological Society, 2003)
      A generalized stability theory (GST) analysis of baroclinic shear flow is performed using primitive equations (PEs), and typical synoptic-scale midlatitudinal values of vertical shear and stratification. GST is a comprehensive ...

    • Structural Stability of Turbulent Jets 

      Farrell, Brian F.; Ioannou, Petros J. (American Meteorological Society, 2003)
      Turbulence in fluids is commonly observed to coexist with relatively large spatial and temporal scale coherent jets. These jets may be steady, vacillate with a definite period, or be irregular. A comprehensive theory for ...

    • Orographic Gravity Waves Close to the Nonhydrostatic Limit of Vertical Propagation 

      Zängl, Günther (American Meteorological Society, 2003)
      Orographic gravity waves excited by a narrow mountain ridge are investigated with the aid of numerical simulations. When the nondimensional mountain half-width Na/U is around 1?N, a, and U being the Brunt?Väisälä frequency, ...

    • A Method for Adjoint Variational Data Assimilation with Physical “On–Off” Processes 

      Mu, Mu; Wang, Jiafeng (American Meteorological Society, 2003)
      Since the accuracy of the tangent linear approximation of moist physics in a mesoscale model is case dependent, the problem related to the variational data assimilation with physical ?on?off? processes is studied further ...

    • Energetics of a Symmetric Circulation Including Momentum Constraints 

      Codoban, Sorin; Shepherd, Theodore G. (American Meteorological Society, 2003)
      A theory of available potential energy (APE) for symmetric circulations, which includes momentum constraints, is presented. The theory is a generalization of the classical theory of APE, which includes only thermal constraints ...

    • Angular Momentum Transports by Moving Spiral Waves 

      Chow, K. C.; Chan, Kwing L. (American Meteorological Society, 2003)
      Theoretical results based on the shallow water equations show that outgoing spiral waves generated by a nonaxisymmetric vortex can effectively remove angular momentum from the vortex, and the removal rate is sensitive to ...

    • Size Distributions and Dynamical Properties of Shallow Cumulus Clouds from Aircraft Observations and Satellite Data 

      Rodts, Stefaan M. A.; Duynkerke, Peter G.; Jonker, Harm J. J. (American Meteorological Society, 2003)
      In this paper aircraft observations of shallow cumulus over Florida during the Small Cumulus Microphysics Study (SCMS) are analyzed. Size distributions of cloud fraction, mass flux, and in-cloud buoyancy flux are derived. ...

    • Piecewise Tendency Diagnosis of Weather Regime Transitions 

      Evans, Katherine J.; Black, Robert X. (American Meteorological Society, 2003)
      Piecewise tendency diagnosis (PTD) is extended and employed to study the dynamics of weather regime transitions. Originally developed for adiabatic and inviscid quasigeostrophic flow on a beta plane, PTD partitions local ...

    • The Contribution of Shear to the Evolution of a Convective Boundary Layer 

      Pino, David; Vilà-Guerau de Arellano, Jordi; Duynkerke, Peter G. (American Meteorological Society, 2003)
      The role of shear in the development and maintenance of a convective boundary layer is studied by means of observations and large eddy simulations (LESs). Particular emphasis is given to the growth of the boundary layer ...

    • A Modeling Study and Scaling Analysis of Orographic Effects on Boundary Layer Shallow Convection 

      Tian, Wenshou; Parker, Douglas J. (American Meteorological Society, 2003)
      Effects of orography on boundary layer shallow convection under various background winds are studied using a two-dimensional model together with scaling analysis. Under a motionless background state the flow response over ...

    • A Two-Dimensional Numerical Study on Diurnal Cycle of Mountain Lee Precipitation 

      Sato, Tomonori; Kimura, Fujio (American Meteorological Society, 2003)
      Simple numerical experiments using a two-dimensional model were conducted to investigate the diurnal variation of water vapor in the lee of a mountain range, which strongly affects nighttime precipitation. In the daytime, ...