
Constraints on drag and exchange coefficients at extreme wind speeds
Author(s) -
Walsh Kevin J. E.,
Sandery P.,
Brassington G. B.,
Entel M.,
SiegenthalerLeDrian C.,
Kepert Jeffrey D.,
Darbyshire R.
Publication year - 2010
Publication title -
journal of geophysical research: oceans
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2009jc005876
Subject(s) - drag coefficient , wind speed , environmental science , atmospheric sciences , meteorology , tropical cyclone , drag , flux (metallurgy) , mixing (physics) , maximum sustained wind , climatology , wind shear , mechanics , wind gradient , geology , physics , materials science , quantum mechanics , metallurgy
Because of the lack of observations, the behavior of air‐sea interfacial flux coefficients at extreme wind speeds is not well known. In this study, simulations of a three‐dimensional ocean model are forced by extreme tropical cyclone winds (up to 155 knots) under various drag and exchange coefficient representations and flux parameterizations. The resulting sea surface temperature changes are compared with satellite observations of sea surface temperature changes caused by three tropical cyclones in the Australian region. The results quantify the impact on oceanic mixing of a drag coefficient that does not monotonically increase with wind speed but instead levels out or decreases at extreme wind speeds, as suggested by recent observations. The results also suggest that mixing parameterizations need to be modified to give realistic surface cooling at extreme wind speeds.