The oceans contribute to aerosol particles in the atmosphere through two different physical mechanisms: first by the production of sea spray aerosol (SSA), and second by emitting gases that condense to produce secondary marine aerosol (SMA). These aerosol emissions include three types of chemical compounds: salt particles account for >90% of the mass, most of which is >1 μm dry diameter; sulfate particles are mostly <0.5 μm, typically constituting most of the number and the largest impacts on clouds; organic components include the greatest variety of compounds and the most uncertain effects on clouds. Most SSA particles are expected to form from bubbles as film drops that are <1 μm dry diameter and form from flapping bursting bubbles, although >1 μm film drops can form by ligament fragmentation. SMA particles include contributions from marine biogenic gas emissions, including dimethylsulfide (DMS), isoprene, amines, and monoterpenes. The role of particles from the ocean in the atmosphere varies by region and by season, but since atmospheric concentrations of ocean-derived <1 μm particles are typically much smaller than the concentrations of their continental counterparts, they have the largest impacts on climate in regions where continental sources are limited. Most efforts to quantify global SSA and SMA emissions rely on global models, where representations of marine aerosol sources are constrained by a small number of field measurements. Satellite-based retrievals of coarse and marine aerosol optical depth provide near global coverage that has been linked to coincident wind speed, whitecaps, and biological productivity for >1 μm particles. The current best estimate of SSA flux of 5000 Tg/yr can be used to calculate SSA-related carbon flux as 35 TgC/yr, by approximating <1 μm SSA particles as 10% of SSA flux with 7% organic carbon and > 1 μm particles as 90% of SSA flux with no organic carbon. SMA is estimated to contribute 0.6 TgC/yr as DMS, 0.6 TgC/yr as amines, and an additional trace amount from isoprene and monoterpenes for a total of <2 TgC/yr. Because of the limited availability of observations to constrain SSA and SMA global estimates, oceanic fluxes to aerosol and aerosol precursors could vary by over two orders of magnitude. Key open questions that require additional observational constraints include the variability in >1 μm SSA mass size distributions, the relative contributions of SSA and SMA to number concentrations of particles <0.5 μm, and the regional and seasonal factors that may control these <0.5 μm particle concentrations.

海洋通过两种不同的物理机制产生大气中的气溶胶颗粒：首先是产生海浪气溶胶 (SSA)，其次是排放气体，这些气体凝结成二次海洋气溶胶 (SMA)。这些气溶胶排放物包括三种类型的化合物：盐颗粒占质量的 90% 以上，其中大部分干径 >1 μm；硫酸盐颗粒大多小于 0.5 μm，通常构成云的大部分数量和最大影响；有机成分包括种类最多的化合物和对云的最不确定影响。预计大多数 SSA 颗粒由气泡形成，如干直径 <1 μm 的膜滴，并由拍打破裂的气泡形成，尽管 >1 μm 的膜滴可以通过韧带碎裂形成。SMA 颗粒包括来自海洋生物气体排放的贡献，包括二甲硫醚 (DMS)、异戊二烯、胺和单萜。来自海洋的颗粒物在大气中的作用因地区和季节而异，但由于大气中源自海洋的 <1 μm 颗粒物的浓度通常远小于大陆对应物的浓度，因此它们对区域气候的影响最大大陆资源有限的地方。大多数量化全球 SSA 和 SMA 排放的努力都依赖于全球模型，其中海洋气溶胶来源的表示受到少量现场测量的限制。基于卫星的粗糙和海洋气溶胶光学深度反演提供了近乎全球的覆盖范围，该覆盖范围与同步风速、白浪和生物生产力相关联 > 1 微米的颗粒。当前对 5000 Tg/yr 的 SSA 通量的最佳估计可用于将 SSA 相关碳通量计算为 35 TgC/yr，方法是将 <1 μm SSA 颗粒近似为 SSA 通量的 10%，有机碳含量为 7%，> 1 μm颗粒为 90% 的 SSA 通量，不含有机碳。据估计，SMA 作为 DMS 贡献 0.6 TgC/yr，作为胺贡献 0.6 TgC/yr，以及来自异戊二烯和单萜的额外痕量，总计 <2 TgC/yr。由于限制 SSA 和 SMA 全球估计的观测资料有限，海洋气溶胶和气溶胶前体通量的变化可能超过两个数量级。需要额外观察限制的关键开放性问题包括 >1 μm SSA 质量分布的可变性、SSA 和 SMA 对 <0.5 μm 颗粒数量浓度的相对贡献，