Editorial Type:
Article
Article Type:
Research Article

Observations of Spatial Variations of Boundary Layer Structure over the Southern Great Plains Cloud and Radiation Testbed

J. M. Hubbe Pacific Northwest National Laboratory, Richland, Washington

Search for other papers by J. M. Hubbe in
Current site
Google Scholar
PubMed Close
,
J. C. Doran Pacific Northwest National Laboratory, Richland, Washington

Search for other papers by J. C. Doran in
Current site
Google Scholar
PubMed Close
,
J. C. Liljegren Pacific Northwest National Laboratory, Richland, Washington

Search for other papers by J. C. Liljegren in
Current site
Google Scholar
PubMed Close
, and
W. J. Shaw Pacific Northwest National Laboratory, Richland, Washington

Search for other papers by W. J. Shaw in
Current site
Google Scholar
PubMed Close
Print Publication:
01 Sep 1997
DOI:
https://doi.org/10.1175/1520-0450(1997)036<1221:OOSVOB>2.0.CO;2
Page(s):
1221–1231
Restricted access

Abstract

Results from a field campaign to study the response of the planetary boundary layer to spatially varying surface conditions are presented. Radiosondes released at four locations with contrasting land use characteristics in the U.S. Department of Energy’s Cloud and Radiation Testbed (CART) in Kansas and Oklahoma showed significant variations in mixed-layer depth, temperature, and water vapor mixing ratios over distances of 100–200 km. Using CART and radiosonde data, estimates of the surface sensible and latent heat fluxes are derived; the results from several methods are compared and a discussion of the similarities and differences in the values is given. Although substantial flux differences among the sites account for some of the variations in the boundary layer behavior, other features of the ambient meteorology and initial conditions appear to be equally important. Despite large changes in mixed-layer and surface-layer temperatures over scales of approximately 100 km, no evidence for temperature-induced secondary circulations was found. A simple scaling argument is presented that gives a possible reason for this absence.

Corresponding author address: J. C. Doran, Pacific Northwest National Laboratory, P.O. Box 999, MSIN K9-30, Richland, WA 99352.

jc_doran@pnl.gov

Abstract

Results from a field campaign to study the response of the planetary boundary layer to spatially varying surface conditions are presented. Radiosondes released at four locations with contrasting land use characteristics in the U.S. Department of Energy’s Cloud and Radiation Testbed (CART) in Kansas and Oklahoma showed significant variations in mixed-layer depth, temperature, and water vapor mixing ratios over distances of 100–200 km. Using CART and radiosonde data, estimates of the surface sensible and latent heat fluxes are derived; the results from several methods are compared and a discussion of the similarities and differences in the values is given. Although substantial flux differences among the sites account for some of the variations in the boundary layer behavior, other features of the ambient meteorology and initial conditions appear to be equally important. Despite large changes in mixed-layer and surface-layer temperatures over scales of approximately 100 km, no evidence for temperature-induced secondary circulations was found. A simple scaling argument is presented that gives a possible reason for this absence.

Corresponding author address: J. C. Doran, Pacific Northwest National Laboratory, P.O. Box 999, MSIN K9-30, Richland, WA 99352.

jc_doran@pnl.gov

Save
Cover Journal of Applied Meteorology and Climatology
Journal of Applied Meteorology and Climatology

  • Avissar, R., and F. Chen, 1993: Development and analysis of prognostic equations for mesoscale kinetic energy and mesoscale (subgrid scale) fluxes for large-scale atmospheric models. J. Atmos. Sci.,50, 3751–3774.

  • Clapp, R. B., and G. M. Hornberger, 1978: Empirical equations for some soil hydraulic properties. WaterResour. Res.,14.4, 601–604.

  • Garratt, J. R., 1992. The Atmospheric Boundary Layer. Cambridge University Press.

  • Hong, X., M. J. Leach, and S. Raman, 1995: A sensitivity study of convective cloud formation by vegetation forcing with different atmospheric conditions. J. Appl. Meteor.,34, 2008–2028.

  • Lynn, B. H., D. Rind, and R. Avissar, 1995: The importance of mesoscale circulations generated by subgrid-scale landscape heterogeneities in general circulation models. J. Climate,8, 191–205.

  • Nuss, W. A., and D. W. Titley, 1994: Use of multiquadric interpolation for meteorological objective analysis. Mon. Wea. Rev.,122, 1611–1631.

  • Pielke, R. A., G. A. Dalu, J. S. Snook, T. J. Lee, and T. G. F. Kittel, 1991: Nonlinear influence of mesoscale land use on weather and climate. J. Climate,4, 1053–1069.

  • Pinty, J.-P., P. Mascart, E. Richard, and R. Rosset, 1989: An investigation of mesoscale flows induced by vegetation inhomogeneities using an evapotranspiration model calibrated against HAPEX-MOBILHY data. J. Appl. Meteor.,28, 976–992.

  • Segal, M., and R. W. Arritt, 1992: Nonclassical mesoscale circulations caused by surface sensible heat-flux gradients. Bull. Amer. Meteor. Soc.,73, 1593–1604.

  • ——, R. Avissar, M. C. McCumber, and R. A. Pielke, 1988: Evaluation of vegetation effects on the generation and modification of mesoscale circulations. J. Atmos. Sci.,45, 2268–2292.

  • ——, W. E. Schreiber, G. Kallos, J. R. Garratt, A. Rodi, J. Weaver, and R. A. Pielke, 1989: The impact of crop areas in northeast Colorado on midsummer mesoscale thermal circulations. Mon. Wea. Rev.,117, 809–825.

  • ——, J. H. Cramer, R. A. Pielke, J. R. Garratt, and P. Hildebrand, 1991: Observational evaluation of the snow breeze. Mon. Wea. Rev.,119, 412–424.

  • Sellers, P. J., C. J. Tucker, G. J. Collatz, S. O. Los, C. O. Justice, D. A. Dazlich, and D. A. Randall, 1994. A global 1° by 1° NDVI data set for climate studies. Part 2: The generation of global fields of terrestrial biophysical parameters from the NDVI. Int. J. Remote Sens.,15, 3519–3545.

  • ——, and Coauthors, 1995: The Boreal Ecosystem–Atmosphere Study (BOREAS): An overview and early results from the 1994 field year. Bull. Amer. Meteor. Soc.,76, 1549–1577.

  • ——, and Coauthors, 1996: A revised land surface parameterization (SiB2) for atmospheric GCMs. Part I: Model formulation. J. Climate,9, 676–705.

  • SGS, 1990: Prototype 1990 conterminous U.S. land cover characteristics data set CD-ROM. EROS Data Center.

  • Zhong, S., and J. C. Doran, 1995: A modeling study of the effects of inhomogeneous surface fluxes in boundary-layer properties. J. Atmos. Sci.,52, 3129–3142.

  • ——, and ——, 1997: A study of the effects of spatially varying fluxes on cloud formation and boundary-layer properties using data from the southern Great Plains cloud and radiation testbed. J. Climate,10, 327–341.

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 192 46 2
PDF Downloads 27 15 1