9505190 Pierrehumbert The research under this award involves and continues research on a family of problems in extratropical, tropospheric synoptic to planetary scale dynamics and the related effects on the Earth's general circulation and seasonal and interannual fluctuations. The theme unifying these studies is an approach to the general circulation based on mixing concepts and the dynamical consequences of homogenized potential vorticity (PV) pools in the troposphere. Four major topics will be pursued: (1) implications of homogenized PV structure for identifying the mechanism for eddy-planetary wave feedback in the troposphere, (2) determination of the effects of radiation and moist processes on the evolution of PV in the atmosphere, (3) statistical equilibrium models of horizontal heat fluxes where upper level vortices are coupled to low level processes, and (4) an extension of previous work in the mixing by synoptic eddies. While Dr. Pierrehumbert deals primarily with highly idealized models, his work provides valuable insights which are applicable to a wide range of research areas. Dr. Pierrehumbert is one of the most creative, original, and productive theoreticians in atmospheric dynamics, for whom this accomplishment-based renewal award is most appropriate.
