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  • Effects of Sea Spray on the Simulated Tropical Cyclone Development: Dependence on Surface Drag Coefficient Parameterization
Title: Effects of Sea Spray on the Simulated Tropical Cyclone Development: Dependence on Surface Drag Coefficient Parameterization
Abstract Wave breaking under strong wind conditions in tropical cyclones (TCs) can generate sea spray droplets, which, during their suspension in air, release sensible heat due to the air‐sea temperature difference while absorb sensible heat from the environment when they evaporate and release latent heat to the environment. Since the spray mass flux is a function of surface drag coefficient (CD), the effect of spray on TC evolution should depends on CDparameterization, while this has not been addressed so far. This study examines the effects of sea spray on the simulated TC evolution with two different CDparameterizations (the Weather Research and Forecasting (WRF) default scheme and the Donelan scheme). Results show that during the primary intensification stage, the TC with spray effect becomes stronger than that without spray when the WRF CDscheme is used, but becomes weaker when the Donelan CDscheme is used. This occurs because CDis maximum outside the radius of maximum wind (RMW) with the Donelan scheme, which produces relatively large spray‐mediated latent heat flux outside the RMW, which is unfavorable for TC intensification. The difference is enlarged by a feedback between spray and TC intensification involving the inertial stability and surface friction‐induced radial inflow. However, in the mature stage, the simulated TCs with spray become stronger no matter which CDscheme is used. In addition, the spray effect on the TC inner‐core size evolution also weakly depends on the drag parameterization. When CDis relatively greater outside the RMW, the inclusion of the spray effect would lead to the inner‐core size increase.  more » « less
Award ID(s):
1834300
PAR ID:
10500598
Author(s) / Creator(s):
; ;
Publisher / Repository:
American Geophysical Union
Date Published:
Journal Name:
Journal of Geophysical Research: Atmospheres
Volume:
128
Issue:
2
ISSN:
2169-897X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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