Insight into Generation and Evolution of Sea-Salt Aerosols from Field Measurements in Diversified Marine and Coastal Atmospheres.

ABSTRACT: This report focuses on studying generation and/or evolution of sea-salt aerosols (SSA) on basis of measurements in the Northwest Pacific Ocean (NWPO), the marginal seas of China, at sea-beach sites and a semi-urban coastal site in 2012-2015. From measurements in the NWPO, we obtained the smallest generation function of the super-micron SSA mass ([M_SSA]) by the local wind comparing to those previously reported. Vessel-caused wave-breaking was found to greatly enhance generation of SSA and increase [M_SSA], which was subject to non-natural generation of SSA. However, naturally enhanced generation of SSA was indeed observed in the marginal seas and at the sea-beach site. The two enhancement mechanisms may explain the difference among this and previous studies. Size distributions of super-micron SSA exhibited two modes, i.e., 1-2??m mode and ~5??m mode. The 1-2??m mode of SSA was enhanced more and comparable to the ~5??m mode under the wind speed >7?m/s. However, the smaller mode SSA was largely reduced from open oceans to sea-beach sites with reducing wind speed. The two super-micron modes were comparable again at a semi-urban coastal site, suggesting that the smaller super-micron mode SSA may play more important roles in atmospheres.

SUBMITTER: Feng L 

PROVIDER: S-EPMC5264635 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature