A statistical comparison of four planetary boundary layer analysis algorithms

The determination of the height of the Planetary Boundary Layer (PBL) is important for accurate transport and diffusion modeling. The PBL height determines the direction and speed of pollution movement, as well as the vertical depth over which the effluent will be mixed. Many methods are used by different models to deduce the height of the PBL from observed upper-air soundings. Fewer methods utilize output from mesoscale numerical weather prediction models (e.g., MM5, RAMS, COAMPS) to determine PBL heights, mainly because the wide use of these models for transport and diffusion modeling has only recently begun. We plan to present results of a study in which PBL heights computed from a variety of methods are compared and contrasted. The methods to be included are a combination of subjective (i.e., human) and objective schemes using both observed upper-air data and model forecast data produced by the Regional Atmospheric Modeling System (RAMS). PBL heights determined using the prognostic fields of turbulent kinetic energy (TKE) available from RAMS will also be included in the study to determine the applicability of this technique.