New England coastal boundary layer modeling

The transition from the continental convective boundary layer to the stable layer over cold water that occurs during pollution episodes in New England has important implications for those episodes and for longer-range transport as well. We present results from two models elucidating specific aspects of the physics of that transition. In particular, we examine the questions:

-- How quickly does the boundary layer stabilize after crossing from land to water? What fluxes are required to accomplish the stabilization?

-- What physical processes create the surface-based inversion? Is shear-driven turbulence sufficient or does advected turbulence also play a role? How intense is the turbulence?

-- Are multiple distinct layers formed from the continental boundary layer after it passes over the water, and if so, how many and how deep is each of the layers?

-- Under what conditions is part of the polluted continental air lofted above a clean marine layer?

-- Does a mixed layer form again downwind, and if so, how far downwind?

-- What is the structure of the pollution plume from the continent in three dimensions? How does it vary with time?