Abstract
In this study we estimate boundary-layer growth and entrainment bycombining radiosonde and micrometeorological observations with asimple coupled boundary-layer and land surface model. A variational(smoothing) approach is used to find the optimal estimate ofentrainment over the daytime window. This method is appealingbecause it accounts for the uncertainty in the various data streams,while enforcing the dynamics of the model (i.e., water and energybudgets in the boundary layer, mixed-layer growth, etc.). Thetraditional variational framework was modified in this study toinclude an ensemble approach, which not only yields a (mean) estimateof entrainment, but a measure of its uncertainty as well. Themethodology is applied to a field experiment site in Kansas. Resultsfrom this study indicate a much larger ratio of entrainment to surfacefluxes compared to early literature values from other sites. However,our results are consistent with recent estimates at the site usingindependent estimation methods. In tests where radiosonde data werewithheld, reasonable skill in entrainment estimation was still shown,suggesting the potential for more widespread applications where onlymicrometeorological data are available. Finally, the data assimilationframework presented here has not traditionally been used inatmospheric boundary-layer studies, and may provide a useful approachfor studying other aspects of the boundary layer in the future.
Similar content being viewed by others
References
Angevine, W. M.: 1999, 'Entrainment Results Including Advection and Case Studies from the Flatland Boundary Layer Experiments', J. Geophys. Res. 104, 30947–30963.
Ball, F. K.: 1960, 'Control of Inversion Height by Surface Heating', Quart. J. Roy. Meteorol. Soc. 86, 483–394.
Barr, A. G. and Betts, A. K.: 1997, 'Radiosonde Boundary-Layer Budgets above a Boreal Forest', J. Geophys. Res. 102, 29205–29212.
Bennett, A.: 1999, Inverse Methods and Data Assimilation, Lecture Notes of the 1999 Summer School at the College of Oceanic and Atmospheric Sciences at Oregon State University, Corvallis, OR, 235 pp.
Bennett, A. F., Chua, B. S., Harrison, D. E., and McPhadden, M. J.: 1998, 'Generalized Inversion of Tropical Atmosphere-Ocean Data and a Coupled Model of the Tropical Pacific', J. Climate 11, 1768–1792.
Betts, A. K.: 1973, 'Non-Precipitating Cumulus Convection and its Parameterization', Quart. J. Roy. Meteorol. Soc. 99, 178–196.
Betts, A. K. and Ball, F. K.: 1994, 'Budget Analysis of FIFE 1987 Sonde Data', J. Geophys. Res. 99, 3655–3666.
Betts, A. K. and Ball, F. K.: 1995, 'The FIFE Surface Diurnal Cycle Climate', J. Geophys. Res. 100(D12), 25679–25693.
Betts, A. K. and Ball, F. K.: 1998, 'FIFE Surface Climate and Site-Averaged Data Set 1987-1989', J. Atmos. Sci. 55, 1091–1108.
Betts, A. K. and Barr, A. G.: 1996, 'First International Satellite Land Surface Climatology Field Experiment 1987 Sonde Budget Revisited', J. Geophys. Res. 101, 23285–23288.
Betts, A. K., Desjardins, R. L., and MacPherson, J. I.: 1992, 'Budget Analysis of the Boundary Layer Grid Flights during FIFE 1987', J. Geophys. Res. 97, 18533–18546.
Betts, A. K., Desjardins, R. L., MacPherson, J. I., and Kelly, R. D.: 1990, 'Boundary Layer Heat and Moisture Budgets from FIFE', Boundary-Layer Meteorol. 50, 109–137.
Carson, D. J.: 1973, 'The Development of a Dry Inversion-Capped Convectively Unstable Boundary Layer', Quart. J. Roy. Meteorol. Soc. 99, 450–467.
Culf, A. D.: 1992, 'An Application of Simple Models to Sahelian Convective Boundary-Layer Growth', Boundary-Layer Meteorol. 58, 1–18.
Driedonks, A. G. M.: 1982, 'Models and Observations of the Growth of the Atmospheric Boundary Layer', Boundary-Layer Meteorol. 23, 283–306.
LeDimet, F.-X. and Talagrand, O.: 1986, 'Variational Algorithms for Analysis and Assimilation of Meteorological Observation: Theoretical Aspects', Tellus 38A, 97–110.
Lenschow, D. H.: 1974, 'Model of the Height Variation of the Turbulence Kinetic Energy Budget in the Unstable Boundary Layer', J. Atmos. Sci. 31, 465–474.
Li, Y., Navon, I. M., Courtier, P., and Gauthier, P.: 1993, 'Variational Data Assimilation with a Semi-Implicit Global ShallowWater EquationModel and its Adjoint', Mon.Wea. Rev. 121, 1759–1769.
Lilly, D. K.: 1968, 'Models of Cloud-Topped Mixed Layer under a Strong Inversion', Quart. J. Roy. Meteorol. Soc. 94, 292–309.
Lu, J. and Hsieh, W. W.: 1997, 'Adjoint Data Assimilation in Coupled Atmosphere-Ocean Model: Determining Model Parameters in a Simple Equatorial Model', Quart. J. Roy. Meteorol. Soc. 123, 2115–2139.
Mahrt, L. and Lenschow, D. H.: 1976, 'Growth Dynamics of the Convectively Mixed Layer', J. Atmos. Sci. 33, 41–51.
Margulis, S. A. and Entekhabi, D.: 2001a, 'A Coupled Land Surface-Boundary Layer Model and its Adjoint', J. Hydrometeorol. 2, 274–296.
Margulis, S.A. and Entekhabi, D.: 2001b, 'Feedback between the Land Surface Eenergy Balance and Atmospheric Boundary Layer Diagnosed through a Model and its Adjoint', J. Hydrometeorol. 2, 599–620.
Margulis, S. A. and Entekhabi, D.: 2003, 'Variational Assimilation of Surface Temperature and Screen-Level Micrometeorology into a Model of the Atmospheric Boundary Land and Land Surface', Mon. Wea. Rev. 131, 1272–1288.
Sellers, P. J., Hall, F. G., Asrar, G., Strebel, D. E., and Murphy, R. E.: 1992, 'An Overview of the First International Satellite and Land Surface Climatology (ISLSCP) Field Experiment (FIFE)', J. Geophys. Res. 97, 18345–18371.
Smeda, M. S.: 1979, 'A Bulk Model for the Atmospheric Planetary Boundary Layer', Boundary-Layer Meteorol. 17, 411–427.
Strebel, D. E., Landis, D. R., Huemmrich, K. F., and Meeson, B. W.: 194, Surface Observations and Non-Image Data Sets, Vol. 1, CD-ROM, NASA, Greenbelt, MD.
Stull, R. B.: 1976, 'Mixed Layer Depth Model Based on Turbulent Energetics', J. Atmos. Sci. 33, 1268–1278.
Stull, R. B.: 1988, An Introduction to Boundary Layer Meteorology, Kluwer Academic Publishers, Dordrecht, 666 pp.
Talagrand, O. and Courtier, P.: 1987, 'Variational Assimilation of Meteorological Observations with the Adjoint Vorticity Equation. I.: Theory', Quart. J. Roy. Meteorol. Soc. 113, 1311–1328.
Tennekes, H.: 1973, 'A Model for the Dynamics of Inversion above a Convective Boundary Layer', J. Atmos. Sci. 30, 558–567.
Thacker, W. C. and Long, R. B.: 1988, 'Fitting Dynamics to Data', J. Geophys. Res. 93, 1227–1240.
Wallace, J. M. and Hobbs, P. V.: 1977, Atmospheric Science: An Introductory Survey, Academic Press, San Diego, 467 pp.
Willis, G. E. and Deardorff, J. W.: 1974, 'A Laboratory Model of the Unstable Planetary Boundary Layer', J. Atmos. Sci. 31, 1297–11307.
Zeman, O. and Tennekes, H.: 1977, Parameterization of the Turbulent Energy Budget at the Top of the Daytime Atmospheric Boundary Layer', J. Atmos. Sci. 34, 111–123.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Margulis, S.A., Entekhabi, D. Boundary-Layer Entrainment Estimation Through Assimilation of Radiosonde and Micrometeorological Data into a Mixed-Layer Model. Boundary-Layer Meteorology 110, 405–433 (2004). https://doi.org/10.1023/B:BOUN.0000007221.53446.46
Issue Date:
DOI: https://doi.org/10.1023/B:BOUN.0000007221.53446.46