Boundary-layer and Mesoscale Meteorology

The atmospheric boundary-layer is the layer of air directly influenced by the underlying surface and is up to two kilometers deep under convective conditions. Students in this field are investigating complex interactions between the air and the ground using observational, theoretical and numerical approaches. Mesoscale meteorology examines similar interactions but on a larger horizontal scale, and can also include modeling of cloud processes.

Select a faculty member's name below to visit their web page.

For further information, visit the Mesoscale Meteorology Group web site.

Shu-Hua Chen

participates in research involving data assimilation and the study of idealized heavy orographic rainfall. A major forecasting problem is that there is not enough in-situ data over the oceans. One of the possibilities for improving model forecasting is to properly utilize remote sensing data to improve model initial conditions. In collaboration with Dr. Francois Vandenberghe at NCAR, Dr. Grant W. Petty at the University of Wisconsin, and Dr. James F. Bresch at NCAR, her group has applied SSM/I and QuikSCAT data to improve hurricane simulations. For heavy orographic rainfall, in collaboration with Dr. Y. L. Lin of North Carolina State University, she has studied the effects of the moist Froude number and the convective available potential energy on flow regimes associated with a conditionally unstable flow over a mesoscale mountain. In addition to these two directions, her research will also be extended to cumulus parameterization and the on-line tracer study in the near future.

Ian Faloona

seeks to develop research spanning the gaps between atmospheric chemistry and turbulent exchange dynamics. He is interested in developing a novel laser spectroscopic technique to measure halogen gases (e.g., HCl) in the atmosphere, yet the ultimate objective is to use the data to learn about both the chemical reactions of the atmosphere as well as the mixing processes which strongly control the ability of compounds to react with one another. Specific current research includes direct eddy-correlation measurements of carbon monoxide (CO) from a coastal marine ecosystem, mixing studies of dimethyl sulfide (DMS) in the stratocumulus topped marine boundary layer, and measurements of formaldehyde (HCHO), an important byproduct of biogenic hydrocarbon oxidation, in a Pine forest in the Sierras.

M. Levent Kavvas

is doing research on the modeling of the evapotranspiration process as it is driven by the boundary- layer dynamics, land surface characteristics and hydrology of subsurface soil moisture.

Bruce White's

research may be divided into two main areas of interest. The first involves fundamental investigation of the physics of turbulent boundary layers. The second area is more practical in nature and may be described as wind-engineering research. The turbulent boundary-layer structure research has been expanded to investigate the effect of adverse pressure gradients on flow structures including both fluid and thermal features. Direct turbulent Prandtl number measurements of adverse-pressure-gradient flows and third-order moments of velocity and temperature for adverse-pressure-gradient flow have been made in the Adverse Pressure Gradient Wind Tunnel Facility, which was designed by Professor White. In the wind-engineering research area, Professor White designed, oversaw construction of, and currently operates the four foot by six foot by 75 foot long UC Davis Atmospheric Boundary Layer Wind Tunnel Graduate Research Facility (ABLWT). Considerable research effort has been placed in the physical modeling of gas dispersion into the atmosphere. A flame-ion-detection system was designed and built and currently operates to model stack emissions and other dispersion processes into the atmosphere. This research led to engineering principles in the relatively new field of environmental laboratory modeling.
Professor White also has been involved in what might be termed Environmental Wind Engineering. This research includes three specific areas of interest: i) the study of large-scale environmental "problems" such as dust-emission suppression at Owens (dry) Lake; ii) Mars/Venus dust/sand storms; and, iii) the study of desert sand transport and dune physics through field testing, laboratory modeling and numerical-analytical analysis.
Two further projects are of interest to Professor White. One involves the physical modeling of radioactive gaseous releases from a stack located in the complex terrain of a mountainous region of California. The other project evaluates the prospect of forecasting wind energy for existing wind parks based on weather forecasts.