Regime‐Dependence of Nocturnal Nitrate Formation via N<sub>2</sub>O<sub>5</sub> Hydrolysis and Its Implication for Mitigating Nitrate Pollution
Pengkun Ma, Jiannong Quan, Youjun Dou, Yubing Pan, Zhiheng Liao, Zhigang Cheng, Xingcan Jia, Qianqian Wang, Junlei Zhan, Wei Ma, Feixue Zheng, Yuzheng Wang, Yusheng Zhang, Chenjie Hua, Chao Yan, Markku Kulmala, Yangang Liu, Yangang Liu, Xin Huang, Bin Yuan, Steven S. Brown, Yongchun Liu, Yongchun Liu
Abstract
Abstract The heterogeneous hydrolysis of dinitrogen pentoxide (N 2 O 5 ) is an important pathway in nitrate formation; however, its formation rate and relative contribution to total particulate nitrate () are highly variable. Here we report that nocturnal formation via N 2 O 5 hydrolysis is dependent on the regime defined by the ratio of NO 2 to O 3 . Nocturnal formation via N 2 O 5 hydrolysis is suppressed in an O 3 ‐limited regime but enhanced in a NO 2 ‐limited regime. The results have crucial implications for effective control of nitrate pollution in the future. An exclusive decrease in NO 2 will decrease nocturnal formation in a NO 2 ‐limited regime but may be less effective or even increase nocturnal formation in an O 3 ‐limited regime.