Effects of the Sea Salt Aerosol On an Idealized Tropical Cyclone Microphysics Using a Bulk Method

Sea Salt Aerosols (SSA) constitute a primary component of atmospheric aerosols over the ocean, playing an important role in Earth's radiation balance, cloud formation, and precipitation processes. These aerosols serve as significant cloud condensation nuclei for marine clouds, with their production influenced by wind speed, sea temperature, and salinity, and are directly emitted from the sea surface via sea spray. Their strong hygroscopic nature allows them to maintain water content even under unsaturated conditions, thereby impacting heat flux, atmospheric water vapor content, cloud droplet water content, and precipitation intensity. Current research either focuses on the effects of SSA emission fluxes on water vapor and heat flux under diverse marine meteorological conditions, often neglecting the microphysical processes of SSA as hydrometeors, or employs computationally intensive microphysical schemes that are not readily applicable in practice. This study calculates SSA emission fluxes based on sea surface temperature and wind speed, applying a computationally efficient bulk parameterization approach for SSA microphysical processes. The methodology is integrated with the WRF numerical model to examine the influence of SSA microphysical processes on the microphysics of tropical cyclones under idealized conditions, with a focus on cloud formation and precipitation processes.