A Numerical Study of the Role of Air-Sea Fluxes in Extratropical Cyclogenesis.
Abstract
This study uses a numerical model to investigate the effect of the air-sea fluxes of sensible heat and moisture in extratropical cyclogenesis over the open ocean. The model is a sectorized version of the UCLA general circulation model including the Arakawa-Schubert cumulus parameterization scheme and the Randall version of the Deardorff planetary boundary layer parameterization. Idealized initial conditions are specified in the atmosphere and ocean that are typical of open-ocean fall and spring conditions. Adiabatic and diabatic model results are compared over a 15-day integration period. Diabatic processes, including the surface fluxes, cause a large reduction in low-level static stability during the initial cyclone growth period. This reduction in static stability, as well as the latent heat release, leads to the rapid growth of wave numbers 12 and 18 in the diabatic model experiment, while only wave number 6 is present in the adiabatic experiment. The growth of the cyclones is much more rapid in the diabatic experiment. However, cyclones in the adiabatic experiment attain similar maximum intensities as in the diabatic experiment, and undergo an analogous decay period.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1981
- Accession Number
- ADA107508
Entities
People
- Scott Alphonse Sandgathe
Organizations
- Naval Postgraduate School