On hurricane energy
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Warm seawater is the energy source for hurricanes. Interfacial sea-to-air heat transfer without spray ranges from 100 W m−2 in light wind to 1,000 W m−2 in hurricane force wind. Spray can increase sea-to-air heat transfer by two orders of magnitude and result in heat transfers of up to 100,000 W m−2. Drops of spray falling back in the sea can be 2–4 °C colder than the drops leaving the sea, thus transferring a large quantity of heat from sea to air. The heat of evaporation is taken from the sensible heat of the remainder of the drop; evaporating approximately 0.3 % of a drop is sufficient to reduce its temperature to the wet bulb temperature of the air. The heat required to evaporate hurricane precipitation is roughly equal to the heat removed from the sea indicating that sea cooling is due to heat removal from above and not to the mixing of cold water from below. The paper shows how case studies of ideal thermodynamic processes can help explain hurricane intensity.
KeywordsHeat Transfer Heat Flux Cooling Tower Convective Available Potential Energy Ocean Heat Content
This article has benefited from discussion with Dr. Nilton Renno, constructive suggestions from two diligent anonymous reviewers and continuing support from journal editor Dr. Michael Kaplan.
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