Publication Date:
2011-10-25
Description:
This study proposes a framework for estimating how much tropical cyclone intensification could result from the amount of energy released inside of a convective burst. A convective burst is a sequence of vigorous convective cells occupying one portion of a tropical cyclone's eyewall for approximately 9 to 24 h. On the basis of Tropical Rainfall Measuring Mission (TRMM) satellite radar observations and previous modeling studies, a typical convective burst may release in 12 h an extra 6 × 1017 J of latent heat. TRMM observations suggest that this extra energy represents an increase of 25% or more in the rate that the eyewall releases latent heat prior to the convective burst. Previous studies suggest that 4.5% to 11% of this extra latent heat may be transformed, after a lag of several hours, into an increase in the kinetic energy of the tropical cyclone's inner-core tangential wind. On the basis of the H*wind analysis of aircraft and dropsonde observations, an increase in kinetic energy of this magnitude may be associated with an intensification of 9–16 m s−1 (17–31 kt) in a tropical cyclone's maximum surface wind. This conservative estimate takes into account the increase in ocean surface friction during the period of intensification and assumes that the associated increase in ocean surface enthalpy flux does not counteract any of the frictional loss. Despite sources of uncertainty, it still appears that significant intensification is possible from the amount of energy released inside of a typical convective burst.
Print ISSN:
0148-0227
Topics:
Geosciences
,
Physics
