Field observations of sea spray under Tropical Cyclone Olwyn

Sea spray comprises liquid droplets that cover a broad range of radii, from 0.01 to 1000 mu m. For field observations, it is difficult to measure the sea spray size distribution over the full range of radii, particularly as spray production is associated with extreme weather conditions. As a result, differences in magnitude of the sea spray production estimates reach 6 orders. In this study, the sea spray volume flux (SSVF) was measured by laser altimeters under Tropical Cyclone Olwyn in the Indian Ocean. The results show that the SSVF increases gradually with the wind speed and is approximately 2 orders of magnitude larger than the results of two laboratory experiments and existing sea spray generation functions. The SSVF is also influenced by the sea state. When the nondimensional significant wave height is factored in a new parameter R-B(u(*)(2)/gH(s))(1/3), the correlation coefficients are improved, increasing to 0.85 and 0.88. Finally, a new parameterization for SSVF generation function is proposed in terms of the nondimensional wave height and windsea Reynolds number R-B.