scholarly journals Chemical interactions between ship-originated air pollutants and ocean-emitted halogens

2021 ◽  
Author(s):  
Qinyi Li ◽  
Alba Badia ◽  
Rafael P. Fernandez ◽  
Anoop S. Mahajan ◽  
Ana Isabel López-Noreña ◽  
...  
Keyword(s):  
Air Pollutants ◽  
Atmospheric Composition ◽  
Chemical Transformations ◽  
Chemical Interactions ◽  
China Sea ◽  
Reactive Halogen Species ◽  
The Impact ◽  
Surface Increase ◽  
Halogen Species

<p>Ocean-going ships supply products from one region to another and contribute to the world’s economy. Ship exhaust contains many air pollutants and results in significant changes in marine atmospheric composition. The role of Reactive Halogen Species (RHS) in the troposphere has received increasing recognition and oceans are the largest contributors to their atmospheric burden. However, the impact of shipping emissions on RHS and that of RHS on ship-originated air pollutants have not been studied in detail. Here, an updated WRF-Chem model is utilized to explore the chemical interactions between ship emissions and oceanic RHS over the East Asia seas in summer. The emissions and resulting chemical transformations from shipping activities increase the level of NO and NO<sub>2</sub> at the surface, increase O<sub>3</sub> in the South China Sea, but decrease O<sub>3</sub> in the East China Sea. Such changes in pollutants result in remarkable changes in the levels of RHS as well as in their partitioning. The abundant RHS, in turn, reshape the loadings of air pollutants and those of the oxidants with marked patterns along the ship tracks. We, therefore, suggest that these important chemical interactions of ship-originated emissions with RHS should be considered in the environmental policy assessments of the role of shipping emissions in air quality and climate.</p>

scholarly journals Ozone pollution around a coastal region of South China Sea: Interaction between marine and continental air

2017 ◽  
Author(s):  
Hao Wang ◽  
Xiaopu Lyu ◽  
Hai Guo ◽  
Yu Wang ◽  
Shichun Zou ◽  
...  
Keyword(s):  
South China Sea ◽  
South China ◽  
Air Pollutants ◽  
Coastal Region ◽  
Oxidative Capacity ◽  
Atmospheric Composition ◽  
Marine Atmosphere ◽  
Ozone Pollution ◽  
China Sea ◽  
Coastal Cities

Abstract. Marine atmosphere is usually considered to be a clean environment, while this study indicates that the near-coast waters of South China Sea (SCS) suffered from even worse air quality than coastal cities. The analyses were based on concurrent field measurements of target air pollutants and meteorological parameters conducted at a suburban site (TC) and a nearby marine site (WS) from August to November 2013. The observations showed that the levels of primary air pollutants were significantly lower at WS than those at TC, while ozone (O3) value was greater at WS. Higher O3 levels at WS were attributed to the weaker NO titration and higher O3 production rate because of stronger oxidative capacity of the atmosphere. However, O3 episodes were concurrently observed at both sites under certain meteorological conditions, such as tropical cyclones, continental anticyclones and sea-land breezes (SLBs). Driven by these synoptic systems and mesoscale recirculations, the interaction between continental and marine air masses had profoundly changed the atmospheric composition and subsequently influenced the formation and redistribution of O3 in the coastal areas. When continental air intruded into marine atmosphere, the O3 pollution was magnified over SCS, and the elevated O3 (> 100 ppbv) could overspread the sea boundary layer ~ 8 times the area of Hong Kong. In some cases, the exaggerated O3 pollution over the SCS was re-circulated to the coastal inshore by sea breeze, leading to even aggravating O3 pollution in coastal cities. The findings are applicable to similar mesoscale environments around the world where the maritime atmosphere is potentially influenced by severe continental air pollution.

scholarly journals Brominated VSLS and their influence on ozone under a changing climate

2017 ◽  
Vol 17 (18) ◽  
pp. 11313-11329 ◽  
Author(s):  
Stefanie Falk ◽  
Björn-Martin Sinnhuber ◽  
Gisèle Krysztofiak ◽  
Patrick Jöckel ◽  
Phoebe Graf ◽  
...  
Keyword(s):  
21St Century ◽  
Atmospheric Chemistry ◽  
Lower Stratosphere ◽  
Atmospheric Transport ◽  
Stratospheric Ozone ◽  
Chemical Transformations ◽  
Mixing Ratios ◽  
Ocean Atmosphere ◽  
The Impact

Abstract. Very short-lived substances (VSLS) contribute as source gases significantly to the tropospheric and stratospheric bromine loading. At present, an estimated 25 % of stratospheric bromine is of oceanic origin. In this study, we investigate how climate change may impact the ocean–atmosphere flux of brominated VSLS, their atmospheric transport, and chemical transformations and evaluate how these changes will affect stratospheric ozone over the 21st century. Under the assumption of fixed ocean water concentrations and RCP6.0 scenario, we find an increase of the ocean–atmosphere flux of brominated VSLS of about 8–10 % by the end of the 21st century compared to present day. A decrease in the tropospheric mixing ratios of VSLS and an increase in the lower stratosphere are attributed to changes in atmospheric chemistry and transport. Our model simulations reveal that this increase is counteracted by a corresponding reduction of inorganic bromine. Therefore the total amount of bromine from VSLS in the stratosphere will not be changed by an increase in upwelling. Part of the increase of VSLS in the tropical lower stratosphere results from an increase in the corresponding tropopause height. As the depletion of stratospheric ozone due to bromine depends also on the availability of chlorine, we find the impact of bromine on stratospheric ozone at the end of the 21st century reduced compared to present day. Thus, these studies highlight the different factors influencing the role of brominated VSLS in a future climate.

AB0229 SHORT-TERM EXPOSURE TO OUTDOOR AIR POLLUTANTS AND RHEUMATOID ARTHRITIS ACTIVITY IN METROPOLITAN AREAS IN THE NORTH OF ITALY

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1415.1-1415
Author(s):  
F. Ingegnoli ◽  
T. Ubiali ◽  
T. Schioppo ◽  
V. Longo ◽  
S. Iodice ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
Air Pollution ◽  
Disease Activity ◽  
Air Pollutants ◽  
Positive Trend ◽  
Inverse Association ◽  
Short Term ◽  
Short Term Exposure ◽  
The Impact

Background:Air pollution is believed to cause oxidative stress and systemic inflammation, that could trigger autoimmunity in rheumatoid arthritis (RA). Several epidemiological studies investigated the possible role of air pollution in the outbreak of RA with controversial results. As far as we know, studies on the effects on disease activity of short-term exposure have not been published.Objectives:To evaluate the impact of short-term exposure to air pollutants (daily mean PM10, PM2.5, NO2and O3) on disease activity in patients with RA.Methods:Consecutive patients with RA (ACR/EULAR Criteria 2010) resident in Lombardy (Italy) were enrolled. In each patient Disease Activity Score on 28 joints (DAS28), Simple Disease Activity Index (SDAI) were assessed. Daily PM10, PM2.5, NO2and O3concentrations, estimated by Regional Environmental Protection Agency at municipality resolution, were used to assign short-term exposure from day of visit back to 14 days. Multivariable linear regression models were performed to identify the day of the pollutants independently associated with disease activity indices, adjusting for the variables significant at the univariate analysis. β coefficients were reported for 1 μg/m3increments of pollutants’ concentrations.Results:422 RA patients were enrolled in the study between January and June 2018: 81.5% females, mean age 58.2±13.3 years, mean disease duration 16.1±11.5 years, 27.3% current smokers, 59.5% RF positivity, 54.5% ACPA positivity. Sparse punctual statistically significant negative associations emerged at the multivariate analysis between PM10, PM2.5, NO2and the outcomes, although with very low estimates, whereas positive associations resulted for O3.Afterwards patients were stratified in 3 subgroups according to their ongoing treatment (no therapy, n=25, conventional synthetic Disease Modifying anti-Rheumatic Drugs -DMARDs-, n=108 and biological or targeted synthetic DMARDs, n=289). A statistical significance was found by analysing the influence of therapy on the interaction between PM2.5and DAS28 (Figure below): a positive trend between PM2.5and DAS28 appeared in the first two groups (no therapy, 0.013±0.007, p=0.06 and csDMARDs, 0.006±0.004, p=0.17), whereas a statistically significant inverse association was seen in the b/tsDMARDs group (-0.005±0.002, p=0.01). Therapy interaction was particularly evident in several days before the visit also for O3.Conclusion:The changes of the outcome measures related to the increase of the pollutants’ levels did not reach the minimal clinically important difference, therefore air pollution seems barely relevant on disease activity once the loss of tolerance is established in RA. O3and PM/NO2always exhibit an opposite performance having inversely proportional atmospheric concentrations, whereas the biological role of this substance is still matter of debate and will need further understanding. Therapy seems to be able to interact with the relation between air pollutants and the parameters considered.Disclosure of Interests:Francesca Ingegnoli: None declared, Tania Ubiali: None declared, Tommaso Schioppo: None declared, Valentina Longo: None declared, Simona Iodice: None declared, Ennio Giulio Favalli Consultant of: Consultant and/or speaker for BMS, Eli-Lilly, MSD, UCB, Pfizer, Sanofi-Genzyme, Novartis, and Abbvie, Speakers bureau: Consultant and/or speaker for BMS, Eli-Lilly, MSD, UCB, Pfizer, Sanofi-Genzyme, Novartis, and Abbvie, Orazio De Lucia: None declared, Antonella Murgo: None declared, Valentina Bollati: None declared, Roberto Caporali Consultant of: AbbVie; Gilead Sciences, Inc.; Lilly; Merck Sharp & Dohme; Celgene; Bristol-Myers Squibb; Pfizer; UCB, Speakers bureau: Abbvie; Bristol-Myers Squibb; Celgene; Lilly; Gilead Sciences, Inc; MSD; Pfizer; Roche; UCB

scholarly journals Importance of reactive halogens in the tropical marine atmosphere: a regional modelling study using WRF-Chem

2019 ◽  
Vol 19 (5) ◽  
pp. 3161-3189 ◽  
Author(s):  
Alba Badia ◽  
Claire E. Reeves ◽  
Alex R. Baker ◽  
Alfonso Saiz-Lopez ◽  
Rainer Volkamer ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Sea Salt ◽  
Heterogeneous Chemistry ◽  
Marine Atmosphere ◽  
Tropical Ocean ◽  
Mixing Ratios ◽  
Reactive Halogen Species ◽  
Inorganic Iodine ◽  
The Impact ◽  
Halogen Species

Abstract. This study investigates the impact of reactive halogen species (RHS, containing chlorine (Cl), bromine (Br) or iodine (I)) on atmospheric chemistry in the tropical troposphere and explores the sensitivity to uncertainties in the fluxes of RHS to the atmosphere and their chemical processing. To do this, the regional chemistry transport model WRF-Chem has been extended to include Br and I, as well as Cl chemistry for the first time, including heterogeneous recycling reactions involving sea-salt aerosol and other particles, reactions of Br and Cl with volatile organic compounds (VOCs), along with oceanic emissions of halocarbons, VOCs and inorganic iodine. The study focuses on the tropical east Pacific using field observations from the Tropical Ocean tRoposphere Exchange of Reactive halogen species and Oxygenated VOC (TORERO) campaign (January–February 2012) to evaluate the model performance. Including all the new processes, the model does a reasonable job reproducing the observed mixing ratios of bromine oxide (BrO) and iodine oxide (IO), albeit with some discrepancies, some of which can be attributed to difficulties in the model's ability to reproduce the observed halocarbons. This is somewhat expected given the large uncertainties in the air–sea fluxes of the halocarbons in a region where there are few observations of their seawater concentrations. We see a considerable impact on the inorganic bromine (Bry) partitioning when heterogeneous chemistry is included, with a greater proportion of the Bry in active forms such as BrO, HOBr and dihalogens. Including debromination of sea salt increases BrO slightly throughout the free troposphere, but in the tropical marine boundary layer, where the sea-salt particles are plentiful and relatively acidic, debromination leads to overestimation of the observed BrO. However, it should be noted that the modelled BrO was extremely sensitive to the inclusion of reactions between Br and the oxygenated VOCs (OVOCs), which convert Br to HBr, a far less reactive form of Bry. Excluding these reactions leads to modelled BrO mixing ratios greater than observed. The reactions between Br and aldehydes were found to be particularly important, despite the model underestimating the amount of aldehydes observed in the atmosphere. There are only small changes to the inorganic iodine (Iy) partitioning and IO when the heterogeneous reactions, primarily on sea salt, are included. Our model results show that tropospheric Ox loss due to halogens ranges between 25 % and 60 %. Uncertainties in the heterogeneous chemistry accounted for a small proportion of this range (25 % to 31 %). This range is in good agreement with other estimates from state-of-the-art atmospheric chemistry models. The upper bound is found when reactions between Br and Cl with VOCs are not included and, consequently, Ox loss by BrOx, ClOx and IOx cycles is high (60 %). With the inclusion of halogens in the troposphere, O3 is reduced by 7 ppbv on average. However, when reactions between Br and Cl with VOCs are not included, O3 is much lower than observed. Therefore, the tropospheric Ox budget is highly sensitive to the inclusion of halogen reactions with VOCs and to the uncertainties in current understanding of these reactions and the abundance of VOCs in the remote marine atmosphere.

scholarly journals Modeling the Impact of Rain on Population Exposed to Air Pollution

2020 ◽  
Vol 21 (3-4) ◽  
pp. 363-370
Author(s):  
Sandeep Sharma ◽  
Nitu Kumari
Keyword(s):  
Mathematical Model ◽  
Air Pollution ◽  
Adverse Effects ◽  
Air Pollutants ◽  
Human Population ◽  
Anthropogenic Activities ◽  
Living Species ◽  
The Impact ◽  
Concentration Of Air Pollutants

AbstractAir pollution is caused by contamination of air due to various natural and anthropogenic activities. The growing air pollution has diverse adverse effects on human health and other living species. However, a significant reduction in the concentration of air pollutants has been observed during the rainy season. Recently, a number of studies have been performed to understand the mechanism of removal of air pollutants due to the rain. These studies have found that rain is helpful in removing many air pollutants from the environment. In this paper, we proposed a mathematical model to investigate the role of rain in the removal of air pollutants and its subsequent impacts on the human population.

scholarly journals Photochemical chlorine and bromine activation from artificial saline snow

2013 ◽  
Vol 13 (19) ◽  
pp. 9789-9800 ◽  
Author(s):  
S. N. Wren ◽  
D. J. Donaldson ◽  
J. P. D. Abbatt
Keyword(s):  
Gas Phase ◽  
High Surface ◽  
High Surface Area ◽  
Ionization Mass ◽  
Heterogeneous Oxidation ◽  
Reactive Halogen Species ◽  
Explosion Mechanism ◽  
Halogen Species ◽  
Snow Samples

Abstract. The activation of reactive halogen species – particularly Cl2 – from sea ice and snow surfaces is not well understood. In this study, we used a photochemical snow reactor coupled to a chemical ionization mass spectrometer to investigate the production of Br2, BrCl and Cl2 from NaCl/NaBr-doped artificial snow samples. At temperatures above the NaCl-water eutectic, illumination of samples (λ > 310 nm) in the presence of gas phase O3 led to the accelerated release of Br2, BrCl and the release of Cl2 in a process that was significantly enhanced by acidity, high surface area and additional gas phase Br2. Cl2 production was only observed when both light and ozone were present. The total halogen release depended on [ozone] and pre-freezing [NaCl]. Our observations support a "halogen explosion" mechanism occurring within the snowpack, which is initiated by heterogeneous oxidation and propagated by Br2 or BrCl photolysis and by recycling of HOBr and HOCl into the snowpack. Our study implicates this important role of active chemistry occurring within the interstitial air of aged (i.e. acidic) snow for halogen activation at polar sunrise.

scholarly journals Ozone pollution around a coastal region of South China Sea: interaction between marine and continental air

2018 ◽  
Vol 18 (6) ◽  
pp. 4277-4295 ◽  
Author(s):  
Hao Wang ◽  
Xiaopu Lyu ◽  
Hai Guo ◽  
Yu Wang ◽  
Shichun Zou ◽  
...  
Keyword(s):  
South China Sea ◽  
South China ◽  
Air Pollutants ◽  
Coastal Region ◽  
Oxidative Capacity ◽  
Atmospheric Composition ◽  
Marine Atmosphere ◽  
Ozone Pollution ◽  
China Sea ◽  
Coastal Cities

Abstract. Marine atmosphere is usually considered to be a clean environment, but this study indicates that the near-coast waters of the South China Sea (SCS) suffer from even worse air quality than coastal cities. The analyses were based on concurrent field measurements of target air pollutants and meteorological parameters conducted at a suburban site (Tung Chung, TC) and a nearby marine site (Wan Shan, WS) from August to November 2013. The observations showed that the levels of primary air pollutants were significantly lower at WS than those at TC, while the ozone (O3) value was greater at WS. Higher O3 levels at WS were attributed to the weaker NO titration and higher O3 production rate because of stronger oxidative capacity of the atmosphere. However, O3 episodes were concurrently observed at both sites under certain meteorological conditions, such as tropical cyclones, continental anticyclones and sea–land breezes (SLBs). Driven by these synoptic systems and mesoscale recirculations, the interaction between continental and marine air masses profoundly changed the atmospheric composition and subsequently influenced the formation and redistribution of O3 in the coastal areas. When continental air intruded into marine atmosphere, the O3 pollution was magnified over the SCS, and the elevated O3 ( >  100 ppbv) could overspread the sea boundary layer  ∼  8 times the area of Hong Kong. In some cases, the exaggerated O3 pollution over the SCS was recirculated to the coastal inshore by sea breeze, leading to aggravated O3 pollution in coastal cities. The findings are applicable to similar mesoscale environments around the world where the maritime atmosphere is potentially influenced by severe continental air pollution.

scholarly journals Brominated VSLS and their influence on ozone under a changing climate

2017 ◽  
Author(s):  
Stefanie Falk ◽  
Björn-Martin Sinnhuber ◽  
Gisèle Krysztofiak ◽  
Patrick Jöckel ◽  
Phoebe Graf ◽  
...  
Keyword(s):  
21St Century ◽  
Atmospheric Chemistry ◽  
Lower Stratosphere ◽  
Atmospheric Transport ◽  
Stratospheric Ozone ◽  
Chemical Transformations ◽  
Mixing Ratios ◽  
Ocean Atmosphere ◽  
The Impact

Abstract. Very short-lived source gases (VSLS) contribute significantly to the tropospheric and stratospheric bromine loading. At present, an estimated 25 % of stratospheric bromine is of oceanic origin. In this study, we investigate how climate change may impact the ocean-atmosphere flux of brominated VSLS, their atmospheric transport, chemical transformations, and evaluate how these changes will affect stratospheric ozone over the 21st century. Under the assumption of fixed ocean water concentrations and RCP6.0 scenario, we find an increase of the ocean-atmosphere flux of brominated VSLS of about 8–10 % by the end of the 21st century compared to present day. A decrease in the tropospheric mixing ratios of VSLS and an increase in the lower stratosphere are attributed to changes in atmospheric chemistry and transport. Our model simulations reveal that, in line with the reduction in the troposphere, the total amount of bromine from VSLS in the stratosphere will decrease during the 21st century. Part of the apparent increase of VSLS in the tropical lower stratosphere results from an increase in the corresponding tropopause height. As the depletion of stratospheric ozone due to bromine depends also on the availability of chlorine, we find the impact of bromine on stratospheric ozone at the end of the 21st century reduced compared to present day. Thus, these studies highlight the different factors influencing the role of brominated VSLS in a future climate.

scholarly journals Enhancement of Photo-bromination of Phenol by Anthraquinone-2-sulphonate and Benzophenone: Implication for Photo-production of Organic Brominated Compounds by Dissolved Organic Matter in Marine Environment

2021 ◽  
Author(s):  
Hui Liu ◽  
Xiaojun Qiu ◽  
Xiaomei Zhu ◽  
Bing Sun ◽  
Xiaoxing Zhang
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Marine Environment ◽  
Bromide Solution ◽  
Reactive Halogen Species ◽  
Organohalogen Compounds ◽  
Halogenation Reaction ◽  
Photo Production ◽  
Halogen Species

Abstract Organobromine compounds are of great ecological risks due to their high toxicity on organisms. Photochemical halogenation reaction may represent an important natural formation process of natural organobromine compounds in marine environment. Here we reported the enhanced formation of bromophenols from phenol by sunlit anthraquinone-2-sulphonate (AQ2S) and benzophenone (BP) in aqueous bromide solutions. Quinones and aromatic ketones are ubiquitous components of dissolved organic matter (DOM) in surface waters, and AQ2S and BP were adopted here as proxies of DOM. Bromophenols’ formation increased with the increasing of the concentrations of AQ2S and BP, and the promotion effect was in the order AQ2S > BP, indicating that sunlit DOM plays an important role for the formation of reactive bromine species. Chloride was found to promote the formation of bromophenols obviously, suggesting a possible role of the mixed reactive halogen species. Finally, the natural DOM from Suwannee River was found to enhance photobromoination at a low concentration (1 mg L-1) in aqueous bromide solution. Our results demonstrated the importance of reactive halogen species generation from sunlit DOM, which possibly contributes to the abiotic source of organohalogen compounds in marine environment.

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