Main content area

Simulation of the effects of sea-salt aerosols on the structure and precipitation of a developed tropical cyclone

Luo, Huan, Jiang, Baolin, Li, Fangzhou, Lin, Wenshi
Atmospheric research 2019 v.217 pp. 120-127
aerosols, chemistry, convection, emissions factor, hurricanes, latent heat, sea level, weather research and forecasting model
The Weather Research and Forecasting model coupled with Chemistry version 3.5.1 is used to investigate the effects of sea-salt aerosols on the tropical cyclone “Rammasun” through three experiments of varying sea-salt emission intensity. The results show that the sea-salt aerosol concentration has a negligible effect on the tropical cyclone track. When the tropical cyclone develops into the mature phase, the minimum sea-level pressure in the control and high emission intensity experiments is 3–4 hPa lower than that in the low intensity experiment. The cloud condensation concentration in the tropical cyclone increases with the growth of sea-salt aerosol emission concentration. The average vertically integrated cloud-condensation nuclei in the low, control and high emission experiments is 3.77 × 104 cm−2, 4.36 × 104 cm−2 and 4.85 × 104 cm−2, respectively. The higher sea-salt aerosol emission leads to a more obvious warm core structure and more latent heat release, which increases the horizontal velocity, convection and convective precipitation. When the tropical cyclone is in the mature phase, the peak value of convective precipitation in the low, control and high emission experiments is 50 mm/h, 52 mm/h and 55 mm/h, respectively. Finally, the higher sea-salt aerosol emission concentration leads to the peak precipitation shifted toward the tropical cyclone center.