Air-Sea interface, Drag coefficient, Hurricane, Kelvin-Helmholtz instability, Marginal stability
The lower limit on the drag coefficient under hurricane force winds is determined by the break-up of the air–sea interface due to Kelvin–Helmholtz instability and formation of the two-phase transition layer consisting of sea spray and air bubbles. As a consequence, a regime of marginal stability develops. In this regime, the air–sea drag coefficient is determined by the turbulence characteristics of the two-phase transition layer. The upper limit on the drag coefficient is determined by the Charnock-type wave resistance. Most of the observational estimates of the drag coefficient obtained in hurricane conditions and in laboratory experiments appear to lie between the two extreme regimes: wave resistance and marginal stability.
Alexander Soloviev and Roger Lukas. 2010. Effects of Bubbles and Sea Spray on Air–Sea Exchange in Hurricane Conditions .Boundary-Layer Meteorology , (3) : 365 -376. https://nsuworks.nova.edu/occ_facarticles/623.