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A Sea-Spray Thermodynamic Parameterization Including Feedback C. W. Fairall *, J-W. Bao, and J. Wilczak NOAA Environmental Technology Laboratory (ETL) Boulder, CO. Background Source strength Feedback Sensitivities. Original Droplet Equations Fairall/Andreas circa 1990.
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A Sea-Spray Thermodynamic Parameterization Including Feedback C. W. Fairall *, J-W. Bao, and J. WilczakNOAA Environmental Technology Laboratory (ETL)Boulder, CO • Background • Source strength • Feedback • Sensitivities
Droplet Source Functions Fairall et al. 1994 Fairall, Banner, Asher Physical Model P energy wave breaking σ surface tension r droplet radius η Kolmogorov microscale f fraction of P going into droplet production Vf=droplet mean fall velocity
Partitioning of Droplet Contribution:Stages of cooling/evaporation • Simplification: consider large droplets that are ejected, cool to wet bulb temperature and re-enter ocean with negligible change in mass • Stages: • Cool from To to Tair = Qs • Cool from Tair to Twet = Ql_a • Evaporation while at Twet = Ql_b • Total droplet enthapy transfer Qse=Qs+Ql_a • Enthalpy Bowen ratio = Qs/Ql_a=(To-Ta)/(Ta-Twet) • Qs=Qse*bowen/(1+bowen)
Feedback Characterization δTa Effect on the fluxes: