We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
A new insight into the vertical differences in NO2 heterogeneous reaction to produce HONO over inland and marginal seas.
- Authors
Xing, Chengzhi; Xu, Shiqi; Song, Yuhang; Liu, Cheng; Liu, Yuhan; Lu, Keding; Tan, Wei; Zhang, Chengxin; Hu, Qihou; Wang, Shanshan; Wu, Hongyu; Lin, Hua
- Abstract
Ship-based multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements were conducted along the marginal seas of China from 19 April to 16 May 2018 to measure the vertical profiles of aerosol, nitrogen dioxide (NO 2), and nitrous acid (HONO). Along the cruise route, we found five hot spots with enhanced tropospheric NO 2 vertical column densities (VCDs) in the Yangtze River Delta, Taiwan Strait, Guangzhou–Hong Kong–Macau Greater Bay Area, port of Zhanjiang, and port of Qingdao. Enhanced HONO concentrations could usually be observed under high-level aerosol and NO 2 conditions, whereas the reverse was not always the case. To understand the impacts of relative humidity (RH), temperature, and aerosol on the heterogeneous reaction of NO 2 to form HONO in different scenarios, the Chinese Academy of Meteorological Sciences (CAMS) and Southern University of Science and Technology (SUST) MAX-DOAS stations were selected as the inland and coastal cases, respectively. The RH turning points in CAMS and SUST cases were both ∼ 65 % (60 %–70 %), whereas two turning peaks (∼ 60 % and ∼ 85 %) of RH were found in the sea cases. As temperature increased, the HONO / NO 2 ratio decreased with peak values appearing at ∼ 12.5 ∘ C in CAMS, whereas the HONO / NO 2 gradually increased and reached peak values at ∼ 31.5 ∘ C in SUST. In the sea cases, when the temperature exceeded 18.0 ∘ C, the HONO / NO 2 ratio rose with increasing temperature and achieved its peak at ∼ 25.0 ∘ C. This indicated that high temperature can contribute to the secondary formation of HONO in the sea atmosphere. In the inland cases, the correlation analysis between HONO and aerosol in the near-surface layer showed that the ground surface is more crucial to the formation of HONO via the heterogeneous reaction of NO 2 ; however, in the coastal and sea cases, the aerosol surface contributed more. Furthermore, we discovered that the conversion rate of NO 2 to HONO through heterogeneous reactions in the sea cases is larger than that in the inland cases in higher atmospheric layers (> 600 m). Three typical events were selected to demonstrate three potential contributing factors of HONO production under marine conditions (i.e., transport, NO 2 heterogeneous reaction, and unknown HONO source). This study elucidates the sea–land and vertical differences in the forming mechanism of HONO via the NO 2 heterogeneous reaction and provides deep insights into tropospheric HONO distribution, transforming process, and environmental effects.
- Subjects
ATMOSPHERIC layers; NITROUS acid; OPTICAL spectroscopy; NITROGEN dioxide; LIGHT absorption; HUMIDITY; TROPOSPHERIC aerosols
- Publication
Atmospheric Chemistry & Physics, 2023, Vol 23, Issue 10, p5815
- ISSN
1680-7316
- Publication type
Article
- DOI
10.5194/acp-23-5815-2023