The grid resolutions typically employed in atmospheric global circulation and mesoscale models are not sufficient to explicitly resolve the turbulence processes within planetary boundary layer (PBL). turbulent fluxes are, therefore, fully parameterized those models, based on empirical relationships for mixing length scale using PBL schemes. However, microscale use large-eddy simulation (LES) te...

We are focused on understanding small-scale processes that influence the ocean’s thermodynamic and dynamic properties on the sub-mesoscale (scales less than 10 km). This includes the role of turbulence in modifying the upper ocean temperature and density structure. In the South China Sea, largeamplitude, nonlinear waves force turbulence in the seasonally variable continental shelf region. New o...

Several studies have examined the sensitivity of fronts and cyclones to model physics over the ocean or flat terrain in mesoscale models (e.g., Zhang et al. 1999). Nonetheless, fewer studies have examined the sensitivity of fronts and cyclones over complex terrain to model physics in the WRF model at very high resolution. Physics parameterizations in the WRF model, including multiple choices of...

This is a research expository paper regarding superparameterization, a class of multi-scale numerical methods designed to cope with the intermittent multi-scale effects of inhomogeneous geophysical turbulence where energy often inverse-cascades from the unresolved scales to the large scales through the effects of waves, jets, vortices, and latent heat release from moist processes. Original as w...

The objective of this effort is to obtain extensive measurements in the MABL under different cloud fractions specially aimed at quantifying various statistical quantities needed to examine and develop PDF-based cloud and turbulence parameterizations. The data set produced will help us understand the characteristics of empirical PDF of various dynamic and thermodynamic variables and their releva...

to enhance the understanding of the impact of obstacle buildings on pollution transportationand dispersion in the atmospheric boundary layer, it is necessary to know the atmospheric flow characteristics over terrains. wind flow characteristics in a boundary layer over a step-shaped cliff topography model with rough and smooth surfaces were studied numerically using computational fluid dynamics ...

This presentation is a summary of research progress supported under the Atmospheric Radiation Measurement (ARM) project entitled "Parameterization of Convective Clouds, Mesoscale Convective Systems, and Con'o'ective-Generated Clouds." The approach used in this research is to perform explicit simulations of convective clouds and mesoscale convective systems for well-documented observed cases. Th...