Nitrous acid in marine boundary layer over eastern Bohai Sea, China: Characteristics, sources, and implications

Abstract. Low-Z particle electron probe X-ray microanalysis (low-Z particle EPMA) shows powerful advantages for the characterization of ambient particulate matter in environmental and geological applications. By the application of the low-Z particle EPMA single particle analysis, an overall examination of 1800 coarse and fine particles (aerodynamic diameters: 2.5–10 μm and 1.0–2.5 μm, respectively) in six samples collected on 28 April–1 May 2006 in the marine boundary layer (MBL) of the Bohai Sea and Yellow Sea was conducted. Three samples (D1, D2, and D3) were collected along the Bohai Bay, Bohai Straits, and Yellow Sea near Korea during an Asian dust storm event while the other three samples (N3, N2, and N1) were collected on normal days. Based on X-ray spectral and secondary electron image data, 15 different types of particles were identified, in which soil-derived particles were encountered with the largest frequency, followed by (C, N, O)-rich droplets (likely the mixture of organic matter and NH4NO3), particles of marine origin, and carbonaceous, Fe-rich, fly ash, and (C, N, O, S)-rich droplet particles. Results show that during the Asian dust storm event relative abundances of the (C, N, O)-rich droplets and the nitrate-containing secondary soil-derived particles were markedly increased (on average by a factor of 4.5 and 2, respectively in coarse fraction and by a factor of 1.9 and 1.5, respectively in fine fraction) in the MBL of the Bohai Sea and Yellow Sea, implying that Asian dust aerosols in springtime are an important carrier of gaseous inorganic nitrogen species, especially NOx (or HNO3) and NH3.

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Is the ocean surface a source of nitrous acid (HONO) in the marine boundary layer?

10.5194/acp-2021-532 ◽

2021 ◽

Author(s):

Leigh Crilley ◽

Louisa Kramer ◽

Francis Pope ◽

Chris Reed ◽

James Lee ◽

...

Keyword(s):

Boundary Layer ◽

Nitrous Acid ◽

Marine Boundary Layer ◽

Ocean Surface ◽

Cape Verde ◽

Formation Mechanisms ◽

Oh Radicals ◽

Surface Source ◽

Global Impacts ◽

Quantitative Understanding

Abstract. Nitrous acid, HONO, is a key net photolytic precursor to OH radicals in the atmospheric boundary later. As OH is the dominant atmospheric oxidant, driving the removal of many primary pollutants and the formation of secondary species, a quantitative understanding of HONO sources is important to predict atmospheric oxidising capacity. While a number of HONO formation mechanisms have been identified, recent work has ascribed significant importance to the dark, ocean-surface mediated conversion of NO2 to HONO in the coastal marine boundary layer. In order to evaluate the role of this mechanism, here we analyse measurements of HONO and related species obtained at two contrasting coastal locations – Cape Verde (Atlantic Ocean), representative of the clean remote tropical marine boundary layer, and Weybourne (United Kingdom), representative of semi-polluted Northern European coastal waters. As expected, higher average concentrations of HONO (70 ppt) were observed in marine air for the more anthropogenically influenced Weybourne location compared to Cape Verde (HONO < 5 ppt). At both sites, the approximately constant HONO/NO2 ratio at night pointed to a low importance for the dark ocean-surface mediated conversion of NO2 into HONO, whereas the midday maximum in the HONO/NO2 ratios indicated significant contributions from photo-enhanced HONO formation mechanisms (or other sources). We obtained an upper limit to the rate coefficient of dark ocean-surface HONO-to-NO2 conversion of CHONO = 0.0011 ppb hr−1 from the Cape Verde observations; this is a factor of 5 lower than the slowest rate reported previously. These results point to significant geographical variation in the predominant HONO formation mechanisms in marine environments and indicate that caution is required when extrapolating the importance of such mechanisms from individual study locations to assess regional and/or global impacts on oxidising capacity. As a significant fraction of atmospheric processing occurs in the marine boundary layer, particularly in the tropics, better constraint of the possible ocean surface source of HONO is important for a quantitative understanding of chemical processing of primary trace gases in the global atmospheric boundary layer and associated impacts upon air pollution and climate.

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Elevated nitrogen-containing particles observed in Asian dust aerosol samples collected at the marine boundary layer of the Bohai Sea and the Yellow Sea

Atmospheric Chemistry and Physics ◽

10.5194/acp-9-6933-2009 ◽

2009 ◽

Vol 9 (18) ◽

pp. 6933-6947 ◽

Cited By ~ 49

Author(s):

H. Geng ◽

Y. Park ◽

H. Hwang ◽

S. Kang ◽

C.-U. Ro

Keyword(s):

Boundary Layer ◽

Yellow Sea ◽

Bohai Sea ◽

Marine Boundary Layer ◽

Asian Dust ◽

Storm Event ◽

X Ray ◽

The Bohai Sea ◽

Three Samples ◽

Dust Storm Event

Abstract. Low-Z particle electron probe X-ray microanalysis (low-Z particle EPMA) shows powerful advantages for the characterization of ambient particulate matter in environmental and geological applications. By the application of the low-Z particle EPMA single particle analysis, an overall examination of 1800 coarse and fine particles (aerodynamic diameters: 2.5–10 μm and 1.0–2.5 μm, respectively) in six samples collected on 28 April–1 May 2006 in the marine boundary layer (MBL) of the Bohai Sea and Yellow Sea was conducted. Three samples (D1, D2, and D3) were collected along the Bohai Bay, Bohai Straits, and Yellow Sea near Korea during an Asian dust storm event while the other three samples (N3, N2, and N1) were collected on non-Asian dust (NAD) days. Based on X-ray spectral and secondary electron image data, 15 different types of particles were identified, in which soil-derived particles were encountered with the largest frequency, followed by (C, N, O)-rich droplets (likely the mixture of organic matter and NH4NO3), particles of marine origin, and carbonaceous, Fe-rich, fly ash, and (C, N, O, S)-rich droplet particles. Results show that during the Asian dust storm event relative abundances of the (C, N, O)-rich droplets and the nitrate-containing secondary soil-derived particles were markedly increased (on average by a factor of 4.5 and 2, respectively in PM2.5−10 fraction and by a factor of 1.9 and 1.5, respectively in PM1.0−2.5 fraction) in the MBL of the Bohai Sea and Yellow Sea, implying that Asian dust aerosols in springtime are an important carrier of gaseous inorganic nitrogen species, especially NOx (or HNO3) and NH3.

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Speciated atmospheric mercury in the marine boundary layer of the Bohai Sea and Yellow Sea

Atmospheric Environment ◽

10.1016/j.atmosenv.2016.02.021 ◽

2016 ◽

Vol 131 ◽

pp. 360-370 ◽

Cited By ~ 18

Author(s):

Chunjie Wang ◽

Zhijia Ci ◽

Zhangwei Wang ◽

Xiaoshan Zhang ◽

Jia Guo

Keyword(s):

Boundary Layer ◽

Yellow Sea ◽

Bohai Sea ◽

Marine Boundary Layer ◽

Atmospheric Mercury ◽

The Bohai Sea

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CARIBIC DOAS observations of nitrous acid and formaldehyde in a large convective cloud

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-13-24343-2013 ◽

2013 ◽

Vol 13 (9) ◽

pp. 24343-24403

Author(s):

K.-P. Heue ◽

H. Riede ◽

D. Walter ◽

C. A. M. Brenninkmeijer ◽

T. Wagner ◽

...

Keyword(s):

Boundary Layer ◽

Detection Limit ◽

Nitrous Acid ◽

World Wide ◽

Marine Boundary Layer ◽

Convective Cloud ◽

Observation System ◽

Oh Radicals ◽

Actual System ◽

The World

Abstract. The CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container) flying laboratory measures once per month the chemical composition at cruise altitude (10...12 km) during 4 consecutive Lufthansa flights. Here we present a case study of enhanced nitrogen oxides (NOx), nitrous acid (HONO), and formaldehyde (HCHO) in a thunderstorm cloud over the Caribbean islands of Guadeloupe in August 2011. Nitrous acid is an important reservoir gas for OH radicals, and only few observations of HONO at cruise altitude exist. CARIBIC is designed as a long period atmospheric observation system, the actual system has been flying almost monthly since 8 yr now. During this period only very few similar events (one since 2008) were observed. Due to multiple scattering the light path inside clouds is enhanced, thereby lowering the detection limit of the DOAS instrument. Under background conditions the detection limits are 46 ppt for HONO, 387 ppt for \\chem{HCHO}, and 100 ppt for NO2 and are roughly three times lower inside the cloud. Based on radiative transfer simulations we estimate the path length to 90{\\ldots}100 km and the cloud top height to ≈15 km. The inferred mixing ratios of HONO, HCHO and NO2 are 37 ppt, 400 ppt and 170 ppt, respectively. Bromine monoxide (BrO) remained below the detection limit of 1 ppt. Because the uplifted air masses originated from the remote marine boundary layer and lightning was observed in the area by the World Wide Lightning Location Network several hours prior to the measurement, the NO (≈1.5 ppb) enhancement was in all likelihood caused by lightning. The main source for the observed HCHO is probably updraught from the boundary layer, because the chemical formation of formaldehyde due to methane oxidation is too weak. Besides HCHO also CH3OOH and isoprene are considered as precursors. The chemical box model CAABA is used to estimate the \\chem{NO} and HCHO source strengths, which are necessary to explain our measurements. For NO a source strength of 8.25 × 109 molec cm−2 s−1 km−1 is found, which corresponds to the lightning activity as observed by the World Wide Lightning Location network and a lightning emission of 4.2 × 1025 NO molec/flash. The HCHO updraught is of the order of 121 × 109 molec cm−2 s−1 km−1. Also isoprene and CH3OOH as possible HCHO sources were studied and similar source strengths were found.

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Supplementary material to "Is the ocean surface a source of nitrous acid (HONO) in the marine boundary layer?"

10.5194/acp-2021-532-supplement ◽

2021 ◽

Author(s):

Leigh Crilley ◽

Louisa Kramer ◽

Francis Pope ◽

Chris Reed ◽

James Lee ◽

...

Keyword(s):

Boundary Layer ◽

Nitrous Acid ◽

Marine Boundary Layer ◽

Ocean Surface ◽

Supplementary Material

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Is the ocean surface a source of nitrous acid (HONO) in the marine boundary layer?

Atmospheric Chemistry and Physics ◽

10.5194/acp-21-18213-2021 ◽

2021 ◽

Vol 21 (24) ◽

pp. 18213-18225

Author(s):

Leigh R. Crilley ◽

Louisa J. Kramer ◽

Francis D. Pope ◽

Chris Reed ◽

James D. Lee ◽

...

Keyword(s):

Boundary Layer ◽

Atmospheric Boundary Layer ◽

Nitrous Acid ◽

Marine Boundary Layer ◽

Ocean Surface ◽

Cape Verde ◽

Formation Mechanisms ◽

Oh Radicals ◽

Surface Source ◽

Quantitative Understanding

Abstract. Nitrous acid, HONO, is a key net photolytic precursor to OH radicals in the atmospheric boundary layer. As OH is the dominant atmospheric oxidant, driving the removal of many primary pollutants and the formation of secondary species, a quantitative understanding of HONO sources is important to predict atmospheric oxidising capacity. While a number of HONO formation mechanisms have been identified, recent work has ascribed significant importance to the dark, ocean-surface-mediated conversion of NO2 to HONO in the coastal marine boundary layer. In order to evaluate the role of this mechanism, here we analyse measurements of HONO and related species obtained at two contrasting coastal locations – Cabo Verde (Atlantic Ocean, denoted Cape Verde herein), representative of the clean remote tropical marine boundary layer, and Weybourne (United Kingdom), representative of semi-polluted northern European coastal waters. As expected, higher average concentrations of HONO (70 ppt) were observed in marine air for the more anthropogenically influenced Weybourne location compared to Cape Verde (HONO < 5 ppt). At both sites, the approximately constant HONO/NO2 ratio at night pointed to a low importance for the dark, ocean-surface-mediated conversion of NO2 into HONO, whereas the midday maximum in the HONO/NO2 ratios indicated significant contributions from photo-enhanced HONO formation mechanisms (or other sources). We obtained an upper limit to the rate coefficient of dark, ocean-surface HONO-to-NO2 conversion of CHONO = 0.0011 ppb h−1 from the Cape Verde observations; this is a factor of 5 lower than the slowest rate reported previously. These results point to significant geographical variation in the predominant HONO formation mechanisms in marine environments and indicate that caution is required when extrapolating the importance of such mechanisms from individual study locations to assess regional and/or global impacts on oxidising capacity. As a significant fraction of atmospheric processing occurs in the marine boundary layer, particularly in the tropics, better constraint of the possible ocean surface source of HONO is important for a quantitative understanding of chemical processing of primary trace gases in the global atmospheric boundary layer and associated impacts upon air pollution and climate.

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