The Sea Spray Generation Function for Large Droplets Based on Sea Salt Aerosol Flux Observation

Abstract

Marine droplets, as the largest natural aerosol source after sand and dust, can have a significant impact on climate change, air pollution, typhoons, and other disaster weather. At present, due to the lack of observational data and insufficient understanding of turbulent transport processes in the air-sea boundary layer, there is considerable uncertainty in the generation function of sea spray droplets, especially for droplets with a particle size greater than 20 μm, most of the generation functions underestimate them. The multiple experiments on observing droplets were conducted in the air-sea boundary layer using a self-developed droplet spectrometer. The concentration and upward velocity of large droplets with particle sizes ranging from 25μm to 1.6 mm were obtained. The sea spray generation function was analyzed using the observed data, and the results showed that the sea salt aerosol (SSA) flux of large droplets was much higher than that given by existing sea spray generation functions, providing a new generation function for large droplets in calculating SSA flux in ocean models.