New mechanism of sea-spray generation and heat-mass transfer under stormy conditions
•Statistical analyses of sequences of frames of high-speed video has enabled us to prove that the dominant spray-generation mechanism in extreme winds relates to the bag-breakup fluid fragmentation regime. It activates at conditions corresponding to Force 8 wind, manifested as “spindrift”.
•Starting from general principles of statistical physics, we develop statistics of the bag-breakup events and determine the spray generation function, which is in good agreement with available experimental data
•Large droplets generated by bag-breakup significantly contribute to enthalpy and momentum flux:
- They significantly increase the air-sea enthalpy flux at hurricane wind
- They enables to explain non-monotonous dependence of surface drag coefficient on wind speed peaking at 35-40 m/s.
The effect is more pronounced for polar low, than for tropical cyclones