Researchers supported under this project will apply a combination of theory, numerical models, and analysis of existing observations to advance understanding of a number of key aspects of hurricane dynamics. The investigators contend that fundamental understanding of underlying atmospheric dynamics has come primarily from studies with balanced models and potential vorticity dynamics. The approach in this proposal will be to examine data with guidance from the basic dynamical concepts developed in theoretical and numerical work. The intellectual merit of this work will come through coordinated examination of a number of specific topics that include: (1) Warm ring thermal structure; (2) balanced wind and mass fields and their relation to eyewall slope; (3) hypersensitivity of intensification rates to eyewall position (as a diabatic heating source relative to the zone of highest inertial stability); (4) Burger's shock structures produced by strong radial inflow in the hurricane boundary layer; (5) lower-stratospheric structure above a hurricane; and (6) inadequacies of the Saffir-Simpson scale. Broader impacts will accrue through training of graduate students, increased interaction between applied mathematics and atmospheric dynamics communities, and the development of user-friendly software for application and exploration simplified dynamical principles that will be made freely available to other researchers. This research will also address a significant issue, viz. the need for improved physical understanding and forecasts of mechanisms leading to rapid changes in the intensity and resulting societal impacts of hurricanes.
