大气中的硝酸盐（NO₃^-）是氮氧化物（NOx）通过与臭氧（O₃）、羟基自由基（OH）等多种氧化剂反应生成的一种关键产物，是大气中的主要污染物之一，对空气质量、气候和生态系统等产生重要影响。本文综述了海洋大气中硝酸盐的生成机制、氧化途径和氮氧同位素特征的全球分布，探讨了不同氧化剂如臭氧和羟基自由基在硝酸盐生成中的作用。结合全球观测数据，发现不同海域和沿海城市的硝酸盐氮氧同位素组成（如δ¹⁵N、δ¹⁸O）具有显著差异，这可能反映了区域内的污染源、光化学条件及大气反应路径的差异。此外，硝酸盐会通过大气沉降进入海洋，对海洋氮循环产生影响。未来研究应加强对全球不同区域的长期监测和数据收集，完善氧化剂贡献的定量评估，从而能更全面地理解大气硝酸盐的生成机制及其对海洋生态系统和气候变化的影响。

Atmospheric nitrate (NO₃^-) is a key product generated through the reaction of nitrogen oxides (NOx) with various oxidants such as ozone (O₃) and hydroxyl radicals (OH). It is one of the main pollutants in the atmosphere, significantly impacting air quality, climate, and ecosystems. This paper reviews the formation mechanisms, oxidation pathways, and global distribution of nitrogen and oxygen isotopic characteristics of nitrate in the marine atmosphere. The role of different oxidants, such as ozone and hydroxyl radicals, in nitrate formation is discussed. Based on global observation data, it is found that the isotopic composition of nitrogen and oxygen in nitrate (such as δ ¹⁵N and δ ¹⁸O) varies significantly across different marine areas and coastal cities, which may reflect regional differences in pollution sources, types of oxidants, photochemical conditions, and atmospheric reaction pathways. In addition, atmospheric nitrate can enter the ocean through atmospheric deposition, influencing the marine nitrogen cycle. Future studies should focus on enhancing long-term monitoring and data collection in different global regions to improve the quantitative assessment of oxidant contributions. This will enable a more comprehensive understanding of the formation mechanisms of atmospheric nitrate and its potential impact on marine ecosystems and climate change.