摘要:

We performed measurements of nitrous acid (HONO) during the PRIDE-PRD2006 campaign in the Pearl River Delta region 60 km north of Guangzhou, China, for 4 weeks in June 2006. HONO was measured by a LOPAP in-situ instrument which was setup in one of the campaign supersites along with a variety of instruments measuring hydroxyl radicals, trace gases, aerosols, and meteorological parameters. Maximum diurnal HONO mixing ratios of 1-5 ppb were observed during the nights. We found that the nighttime build-up of HONO can be attributed to the heterogeneous NO2 to HONO conversion on ground surfaces and the OH + NO reaction. In addition to elevated nighttime mixing ratios, measured noontime values of approximate to 200 ppt indicate the existence of a daytime source higher than the OH + NO -> HONO reaction. Using the simultaneously recorded OH, NO, and HONO photolysis frequency, a daytime additional source strength of HONO (P-M) was calculated to be 0.77 ppb h(-1) on average. This value compares well to previous measurements in other environments. Our analysis of P-M provides evidence that the photolysis of HNO3 adsorbed on ground surfaces contributes to the HONO formation.

附注:

Atmos. Chem. Phys.3ArticleISI Document Delivery No.: 897ND Times Cited: 0 Cited Reference Count: 71 Li, X. Brauers, T. Haeseler, R. Bohn, B. Fuchs, H. Hofzumahaus, A. Holland, F. Lou, S. Lu, K. D. Rohrer, F. Hu, M. Zeng, L. M. Zhang, Y. H. Garland, R. M. Su, H. Nowak, A. Wiedensohler, A. Takegawa, N. Shao, M. Wahner, A. China National Basic Research and Development Program[2002CB410801]; National High Technology Research and Development Program of China (863 Program)[2006AA06A301] This work was supported by the China National Basic Research and Development Program 2002CB410801, and the National High Technology Research and Development Program of China (863 Program) 2006AA06A301. COPERNICUS GESELLSCHAFT MBH GOTTINGEN