1. Shanghai Academy of Environmental Sciences, Shanghai 200233, China; 2. State Environmental Protection Key Laboratory of the Cause and Prevention of Urban Air Pollution Complex, Shanghai 200233, China
Abstract:Continuous measurements of HONO and related pollutants were conducted in the urban area of Shanghai from November 6, 2022, to January 2, 2023. By combining box model simulations, the concentrations, characteristics, and sources of winter HONO in Shanghai urban area were obtained. The results showed that the average concentration of HONO was (1.17±0.82)×10-9, with a concentration range of (0.078~5.32)×10-9. The average concentration of HONO in pollution days was significantly higher than that in clean days, showing an increase of approximately 67.2%. HONO exhibited diurnal variation, with higher concentrations at night and lower concentrations during the day, similar to the diurnal variation of NOx. Analysis of correlations between HONOcorr and various influencing factors indicated that the heterogeneous conversion of NO2 was the main source of HONO during nighttime, while both homogeneous and heterogeneous reactions (including photo-enhanced conversion) were dominate sources during daytime. Box model simulations suggested that daytime sources of HONO primarily were photo-enhanced conversion of NO2 on ground surfaces and homogeneous reactions involving OH and NO2. The average HONO formation rates in pollution days were 0.21 and 0.16×10-9/h, respectively. During nighttime, the dominate sources were NO2 conversion on ground surfaces and primary emissions. The increase in PM2.5 and its chemical species during nighttime lead to an increased contribution from NO2 photo-enhanced conversion on various surfaces.
[1] Xue C, Zhang C, Ye C, et al. HONO budget and its role in nitrate formation in the rural North China Plain [J]. Environ. Sci. Technol., 2020,54(18):11048-11057. [2] Liu P, Xue C, Ye C, et al. The lack of HONO measurement may affect the accurate diagnosis of ozone production sensitivity [J]. ACS Environmental Au, 2023,3(1):18-23. [3] Yang Y, Li X, Zu K, et al. Elucidating the effect of HONO on O3 pollution by a case study in southwest China [J]. Sci. Total. Environ., 2021,756:144127. [4] Li Y, Wang X, Wu Z, et al. Atmospheric nitrous acid (HONO) in an alternate process of haze pollution and ozone pollution in urban Beijing in summertime: Variations, sources and contribution to atmospheric photochemistry [J]. Atmospheric Research, 2021,260. [5] Zhang W, Tong S, Lin D, et al. Atmospheric chemistry of nitrous acid and its effects on hydroxyl radical and ozone at the urban area of Beijing in early spring 2021[J]. Environmental Pollution, 2023,316:120710. [6] Yu Y, Cheng P, Li H, et al. Budget of nitrous acid (HONO) at an urban site in the fall season of Guangzhou, China [J]. Atmospheric Chemistry and Physics, 2022,22(13):8951-8971. [7] Liu Y, Lu K, Li X, et al. A comprehensive model test of the HONO sources constrained to field measurements at rural North China Plain [J]. Environ Sci Technol, 2019,53(7):3517-3525. [8] Alicke B. Impact of nitrous acid photolysis on the total hydroxyl radical budget during the Limitation of Oxidant Production/Pianura Padana Produzione di Ozono study in Milan [J]. Journal of Geophysical Research, 2002,107(D22):8196-8204. [9] Hu B, Duan J, Hong Y, et al. Exploration of the atmospheric chemistry of nitrous acid in a coastal city of southeastern China: results from measurements across four seasons [J]. Atmospheric Chemistry and Physics, 2022,22(1):371-393. [10] Su H, Cheng Y, Oswald R, et al. Soil nitrite as a source of atmospheric HONO and OH radicals [J]. Science, 2011,333(6049):1616-1618. [11] Tang K, Qin M, Duan J, et al. A dual dynamic chamber system based on IBBCEAS for measuring fluxes of nitrous acid in agricultural fields in the North China Plain [J]. Atmospheric Environment, 2019,196:10-19. [12] Nie W, Ding A J, Xie Y N, et al. Influence of biomass burning plumes on HONO chemistry in eastern China [J]. Atmospheric Chemistry and Physics, 2015,15(3):1147-1159. [13] Xu Z, Wang T, Wu J, et al. Nitrous acid (HONO) in a polluted subtropical atmosphere: Seasonal variability, direct vehicle emissions and heterogeneous production at ground surface [J]. Atmospheric Environment, 2015,106:100-109. [14] Trinh H T, Imanishi K, Morikawa T, et al. Gaseous nitrous acid (HONO) and nitrogen oxides NOx emission from gasoline and diesel vehicles under real-world driving test cycles [J]. J Air Waste Manag Assoc, 2017,67(4):412-420. [15] Nakashima Y, Sadanaga Y, Saito S, et al. Contributions of vehicular emissions and secondary formation to nitrous acid concentrations in ambient urban air in Tokyo in the winter [J]. Sci Total Environ, 2017, 592:178-186. [16] Liu Y, Lu K, Ma Y, et al. Direct emission of nitrous acid (HONO) from gasoline cars in China determined by vehicle chassis dynamometer experiments [J]. Atmospheric Environment, 2017,169:89-96. [17] Kurtenbach R, Becker K H, Gomes J a G, et al. Investigations of emissions and heterogeneous formation of HONO in a road traffic tunnel [J]. Atmospheric Environment, 2001,35:3385-3394. [18] Yang Q, Su H, Li X, et al. Daytime HONO formation in the suburban area of the megacity Beijing, China [J]. Science China Chemistry, 2014,57(7):1032-1042. [19] Liu Y, Nie W, Xu Z, et al. Semi-quantitative understanding of source contribution to nitrous acid (HONO) based on 1 year of continuous observation at the SORPES station in eastern China [J]. Atmospheric Chemistry and Physics, 2019,19(20):13289-13308. [20] Jia C, Tong S, Zhang W, et al. Pollution characteristics and potential sources of nitrous acid (HONO) in early autumn 2018 of Beijing [J]. Sci Total Environ, 2020,735:139317. [21] Oswald R, Behrendt T, Ermel M, et al. HONO emissions from soil bacteria as a major source of atmospheric reactive nitrogen [J]. Science, 2013,341(6151):1233-1235. [22] Xue C, Ye C, Zhang C, et al. Evidence for strong HONO Emission from fertilized agricultural fields and its remarkable impact on regional O3 pollution in the summer North China Plain [J]. ACS Earth and Space Chemistry, 2021,5(2):340-347. [23] Wang Y, Ge C, Castro Garcia L, et al. Improved modelling of soil NOx emissions in a high temperature agricultural region: role of background emissions on NO2 trend over the US [J]. Environmental Research Letters, 2021,16(8):084061. [24] Gu R, Shen H, Xue L, et al. Investigating the sources of atmospheric nitrous acid (HONO) in the megacity of Beijing, China [J]. Sci. Total Environ., 2022,812:152270. [25] Su H, Cheng Y F, Cheng P, et al. Observation of nighttime nitrous acid (HONO) formation at a non-urban site during PRIDE-PRD2004 in China [J]. Atmospheric Environment, 2008,42(25):6219-6232. [26] Li X, Brauers T, Häseler R, et al. Exploring the atmospheric chemistry of nitrous acid (HONO) at a rural site in Southern China [J]. Atmospheric Chemistry and Physics, 2012,12(3):1497-1513. [27] Su H, Cheng Y F, Shao M, et al. Nitrous acid (HONO) and its daytime sources at a rural site during the 2004PRIDE-PRD experiment in China [J]. Journal of Geophysical Research, 2008,113(D14). [28] Zhang X, Tong S, Jia C, et al. Elucidating HONO formation mechanism and its essential contribution to OH during haze events [J]. npj Climate and Atmospheric Science, 2023,6(1):55-64. [29] Zhang X, Tong S, Jia C, et al. The levels and sources of nitrous acid (HONO) in winter of Beijing and Sanmenxia [J]. Journal of Geophysical Research: Atmospheres, 2022,127(10):e2021JD036278. [30] Zhang W, Tong S, Hou S, et al. Machine learning revealing key factors influencing HONO chemistry in Beijing during heating and non-heating periods [J]. Atmospheric Research, 2024,298. [31] Jenkin M E, Young J C, Rickard A R. The MCM v3.3.1degradation scheme for isoprene [J]. Atmos. Chem. Phys., 2015,15(20):11433-11459. [32] Wolfe G M, Marvin M R, Roberts S J, et al. The Framework for 0-D Atmospheric Modeling (F0AM) v3.1[J]. 2016,9:3309-3319. [33] 王雪瑶,何翔,林登.大气中HONO去除途径的研究进展[J]. 中国环境科学, 2023,43(5):2152-2160. Wang X Y, He X, Lin D. Advances in the removal processes of HONO in the atmosphere [J]. China Environmental Science, 2023,43(5): 2152-2160. [34] Zang H, Zhao Y, Huo J, et al. High atmospheric oxidation capacity drives wintertime nitrate pollution in the eastern Yangtze River Delta of China [J]. Atmospheric Chemistry and Physics, 2022,22(7):4355-4374. [35] Stemmler K, Ammann M, Donders C, et al. Photosensitized reduction of nitrogen dioxide on humic acid as a source of nitrous acid [J]. Nature, 2006,440(7081):195-198. [36] 张奕,曹芳,范美益,等.南京市冬夏季HONO浓度水平及生成机制[J]. 环境科学, 2024:1-13. Zhang Y, Cao F, Fan M Y, et al. Atmospheric HONO concentration levels and generation mechanisms in Nanjing in winter and summer [J]. Environmental Science, 2024:1-13. [37] 姜震,唐梦雪,邵宇铭,等.深圳大气中亚硝酸和甲醛的四季污染特征[J]. 中国环境科学, 2024,44(6):2961-2969. Jiang Z, Tang M X, Shao Y M, et al. Pollution characteristics of nitrous acid and formaldehyde during the four seasons in Shenzhen [J]. China Environmental Science, 2024,44(6):2961-2969. [38] Feng J, Ren E, Hu M, et al. Budget of atmospheric nitrous acid (HONO) during the haze and clean periods in Shanghai: Importance of heterogeneous reactions [J]. Sci. Total. Environ., 2023,900:165717. [39] Yu Y, Galle B, Panday A, et al. Observations of high rates of NO2-HONO conversion in the nocturnal atmospheric boundary layer in Kathmandu, Nepal [J]. Atmos. Chem. Phys., 2009,9:6401-6415. [40] Lee J D, Whalley L K, Heard D E, et al. Detailed budget analysis of HONO in central London reveals a missing daytime source [J]. Atmospheric Chemistry and Physics, 2016,16(5):2747-2764.