Oceanic Supply of Ice-Nucleating Particles and Its Effect on Ice Cloud Formation: A Case Study in the Arctic Ocean During a Cold-Air Outbreak in Early Winter

Abstract

The relationship between cloud phase, ice-nucleating particles (INPs), and ocean state is vital in climate system modeling. High wave conditions induced by the Arctic sea-ice decline and intensified atmospheric forcing over the ice-free ocean increase dynamical geochemical oceanic mixing and sea spray supply containing organic substances, which could act as INPs promoting formation of lower tropospheric ice-containing clouds. Here, we show that the surface ocean state regulates INP concentration and ice cloud presence in the boundary layer. Arctic research cruise data from the marginal ice zone in the Chukchi Sea in November 2018 revealed high number concentrations of INPs active greater than (Formula presented.) °C and ice-containing clouds under high wave conditions. Chemical analysis revealed high contents of organic carbon and sea salt that coincided with the increased oceanic turbidity. The findings suggest that elevated levels of marine organics will contribute to modification of cloud phase from liquid droplets to ice crystals.