First direct measurements of enthalpy flux in the hurricane boundary layer: The CBLAST results

Jun A. Zhang, Peter G. Black, Jeffrey R. French, William M Drennan

Research output: Contribution to journalArticle

99 Citations (Scopus)

Abstract

Hurricanes extract energy from the warm ocean through enthalpy fluxes. As part of the Coupled Boundary Layer Air-Sea Transfer (CBLAST) experiment, flights were conducted to measure turbulent fluxes in the high-wind boundary layer of hurricanes. Here we present the first field observations of sensible heat and enthalpy flux for 10m wind speeds to 30 ms-1. The analyses indicate no statistically significant dependence of these bulk exchange coefficients on wind speed. As a measure of hurricane development potential, we compute the mean ratio of the exchange coefficient for enthalpy to that for momentum and find it to be significantly below the lowest threshold estimated by previous investigators. This suggests that the enthalpy flux required for hurricane development may come from sources other than turbulent fluxes, such as lateral fluxes from the vortex warm core, or sea spray. Alternatively, it demands a re-evaluation of the theoretical models used to derive the threshold.

Original languageEnglish (US)
Article numberL14813
JournalGeophysical Research Letters
Volume35
Issue number14
DOIs
StatePublished - Jul 28 2008

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hurricanes
enthalpy
hurricane
boundary layers
boundary layer
air
wind velocity
spray
vortex
momentum
thresholds
flight
coefficients
sprayers
sea
heat flux
oceans
ocean
vortices
energy

ASJC Scopus subject areas

  • Earth and Planetary Sciences(all)
  • Geophysics

Cite this

First direct measurements of enthalpy flux in the hurricane boundary layer : The CBLAST results. / Zhang, Jun A.; Black, Peter G.; French, Jeffrey R.; Drennan, William M.

In: Geophysical Research Letters, Vol. 35, No. 14, L14813, 28.07.2008.

Research output: Contribution to journalArticle

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