TITLE

Parameterization of PBL Processes in an Atmospheric General Circulation Model: Description and Preliminary Assessment

AUTHOR(S)
Konor, Celal S.; Cazes Boezio, Gabriel; Mechoso, Carlos R.; Arakawa, Akio
PUB. DATE
March 2009
SOURCE
Monthly Weather Review;Mar2009, Vol. 137 Issue 3, p1061
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
This paper presents the basic features of a newly developed planetary boundary layer (PBL) parameterization, and the performance assessment of a version of the University of California, Los Angeles (UCLA), Atmospheric General Circulation Model (AGCM) to which the parameterization is incorporated. The UCLA AGCM traditionally uses a framework in which a sigma-type vertical coordinate for the PBL shares a coordinate surface with the free atmosphere at the PBL top. This framework facilitates an explicit representation of processes concentrated near the PBL top, which is crucially important especially for predicting PBL clouds. In the new framework, multiple layers are introduced between the PBL top and earth's surface, allowing for predictions of the vertical profiles of potential temperature, total water mixing ratio, and horizontal winds within the PBL. The vertically integrated “bulk” turbulent kinetic energy (TKE) is also predicted for the PBL. The PBL-top mass entrainment is determined through an equation including the effects of TKE and the radiative and evaporative cooling processes concentrated near the PBL top. The surface fluxes are determined from an aerodynamic formula in which the velocity scale depends both on the square root of TKE and the grid-scale PBL velocity at the lowermost model layer. The turbulent fluxes within the PBL are determined through an approach that includes the effects of both large convective and small diffusive eddies. AGCM simulations with the new formulation of PBL are analyzed with a focus on the seasonal and diurnal variations. The simulated seasonal cycle of stratocumulus over the eastern oceans is realistic, as are the diurnal cycles of the PBL depth and precipitation over land. The simulated fluxes of latent heat, momentum, and shortwave radiation at the ocean surface and baroclinic activity in the middle latitudes show significant improvements over the previous versions of the AGCM based on the single-layer PBL.
ACCESSION #
38016327

 

Related Articles

  • Including Radiative Effects in an Entrainment Rate Formula for Buoyancy-Driven PBLs. Moeng, Chin-Hoh; Sullivan, Peter P. // Journal of the Atmospheric Sciences;4/15/99, Vol. 56 Issue 8, p1031 

    Studies the effect of longwave radiative cooling at the planetary boundary layer (PBL) on entrainment rate. Steps in deriving entrainment rate equation; Review of the commonly used entrainment rate equation; Use of the large eddy simulation (LES) technique; LES results; Other basis of...

  • Estimating convective atmospheric boundary layer depth from microwave radar imagery of the sea... Sikora, Todd D.; Young, George S. // Journal of Applied Meteorology;Jul97, Vol. 36 Issue 7, p833 

    States that the synthetic aperture radar imagery of the sea surface can be linked to the presence of microscale cellular convection in the marine atmospheric boundary layer. Information on studies conducted; Reference to hypotheses on the issue.

  • Atmospheric Circulations Induced by a Midlatitude SST Front: A GCM Study. Brachet, Sidonie; Codron, Francis; Feliks, Yizhak; Ghil, Michael; Le Treut, Herv; Simonnet, Eric // Journal of Climate;Mar2012, Vol. 25 Issue 6, p1847 

    The atmospheric effects of sea surface temperature (SST) anomalies over and near western boundary currents are a matter of renewed interest. The general circulation model (GCM) of the Laboratoire de Météorologie Dynamique (LMD-Z) has a zooming capability that allows a regionally increased...

  • IL-GLOBO (1.0) -- development and verification of the moist convection module. Rossi, D.; Maurizi, A.; Fantini, M. // Geoscientific Model Development Discussions;2015, Vol. 8 Issue 9, p8239 

    The development and verification of the convective module of IL-GLOBO, a Lagrangian transport model coupled online with the Eulerian general circulation model GLOBO, is described. The online-coupling promotes the full consistency between the Eulerian and the Lagrangian components of the model....

  • Impacts of Evaporation from Raindrops on Tropical Cyclones. Part I: Evolution and Axisymmetric Structure. Sawada, Masahiro; Iwasaki, Toshiki // Journal of the Atmospheric Sciences;Jan2010, Vol. 67 Issue 1, p71 

    Cloud-resolving simulations of an ideal tropical cyclone (TC) on an f plane are performed to investigate the effects of evaporative cooling on the evolution and structure of a TC. Evaporative cooling has markedly different impacts on the TC development and structure than melting/sublimation...

  • FORUM ON MODELING THE ATMOSPHERIC BOUNDARY LAYER. Pielke Sr., Roger A.; Vukicevic, Tomislava // Bulletin of the American Meteorological Society;Jan2005, Vol. 86 Issue 1, p95 

    Focuses on the meeting convened by the U.S. Army Research Laboratory and the Department of Defense Center for Geoscience/Atmospheric Research at Colorado State University with seven major mesoscale modeling groups in Fort Collins, Colorado. Presentation of the technical descriptions of specific...

  • Investigation of Regional and Seasonal Variations in Marine Boundary Layer Cloud Properties from MODIS Observations. Jensen, Michael P.; Vogelmann, Andrew M.; Collins, William D.; Zhang, Guang J.; Luke, Edward P. // Journal of Climate;Oct2008, Vol. 21 Issue 19, p4955 

    To aid in understanding the role that marine boundary layer (MBL) clouds play in climate and assist in improving their representations in general circulation models (GCMs), their long-term microphysical and macroscale characteristics are quantified using observations from the Moderate Resolution...

  • Sensitivity of the Upper Mesosphere to the Lorenz Energy Cycle of the Troposphere. Becker, Erich // Journal of the Atmospheric Sciences;Mar2009, Vol. 66 Issue 3, p647 

    The concept of a mechanistic general circulation model that explicitly simulates the gravity wave drag in the extratropical upper mesosphere in a self-consistent fashion is proposed. The methodology consists of 1) a standard spectral dynamical core with high resolution, 2) idealized formulations...

  • Quantifying Differences between 2-m Temperature Observations and Reanalysis Pressure-Level Temperatures in Northwestern North America. Reuten, Christian; Moore, R. Dan; Clarke, Garry K. C. // Journal of Applied Meteorology & Climatology;Apr2011, Vol. 50 Issue 4, p916 

    In northwestern North America, which is a large area with complex physiography, Climatic Research Unit (CRU) Time Series, version 2.1, (TS 2.1) gridded monthly mean 2-m temperatures are systematically lower than interpolated monthly averaged North American Regional Reanalysis (NARR)...

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics