While the larger-scale aspects of fronts and cyclones has been studied for some years, the regional and local-scale characteristics are not as well known. This research aims to extend prior studies of the structure, dynamics, and precipitation distribution associated with occluded winter cyclones. This work will be accomplished through employment of a case study approach involving analysis of observations and diagnosis of output from high resolution numerical simulations of selected events performed using an advanced mesoscale numerical model.
A component of the research will focus on documenting the fine-scale structure and precipitation distribution of warm occlusions using the unprecedented observational data set collected during the recent SNOWBAND field experiment. Questions regarding the mesoscale structure of warm occlusions as well as the mesoscale dynamical processes responsible for the production and sustenance of heavy snowbands in the occluded sector of cyclones will be addressed in this component of the research.
Investigation of the ageostrophic dynamics operating in the occluded sector along with an examination of the evolution of the static stability in the occluded quadrant are also components of the research. In addition, piece-wise potential vorticity (PV) diagnostics will be employed to specifically examine the role of discrete PV anomalies in altering the frontal structure of mature cyclones.
Successful completion of this research should produce important advances in understanding of the processes that contribute to the structure, dynamics and precipitation distribution characteristic of extratropical cyclones.
