Biogenic halocarbons from the Peruvian upwelling region as tropospheric halogen source

Abstract. Halocarbons, halogenated short-chained hydrocarbons, are produced naturally in the oceans by biological and chemical processes. They are emitted from surface seawater into the atmosphere, where they take part in numerous chemical processes such as ozone destruction and the oxidation of mercury and dimethyl sulfide. Here we present oceanic and atmospheric halocarbon data for the Peruvian upwelling obtained during the M91 cruise onboard the research vessel Meteor in December 2012. Surface waters during the cruise were characterized by moderate concentrations of bromoform (CHBr3) and dibromomethane (CH2Br2) correlating with diatom biomass derived from marker pigment concentrations, which suggests this phytoplankton group as likely source. Concentrations measured for the iodinated compounds methyl iodide (CH3I) of up to 35.4 pmol L−1, chloroiodomethane (CH2ClI) of up to 58.1 pmol L−1 and diiodomethane (CH2I2) of up to 32.4 pmol L−1 in water samples were much higher than previously reported for the tropical Atlantic upwelling systems. Iodocarbons also correlated with the diatom biomass and even more significantly with dissolved organic matter (DOM) components measured in the surface water. Our results suggest a biological source of these compounds as significant driving factor for the observed large iodocarbon concentrations. Elevated atmospheric mixing ratios of CH3I (up to 3.2 ppt), CH2ClI (up to 2.5 ppt) and CH2I2 (3.3 ppt) above the upwelling were correlated with seawater concentrations and high sea-to-air fluxes. The enhanced iodocarbon production in the Peruvian upwelling contributed significantly to tropospheric iodine levels.

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Biogenic halocarbons from the Peruvian upwelling region as tropospheric halogen source

Atmospheric Chemistry and Physics ◽

10.5194/acp-16-12219-2016 ◽

2016 ◽

Vol 16 (18) ◽

pp. 12219-12237 ◽

Cited By ~ 9

Author(s):

Helmke Hepach ◽

Birgit Quack ◽

Susann Tegtmeier ◽

Anja Engel ◽

Astrid Bracher ◽

...

Keyword(s):

Surface Waters ◽

Dimethyl Sulfide ◽

Chemical Processes ◽

Driving Factor ◽

Tropical Atlantic ◽

Surface Seawater ◽

Mixing Ratios ◽

Ozone Destruction ◽

Biological Source ◽

Phytoplankton Group

Abstract. Halocarbons are produced naturally in the oceans by biological and chemical processes. They are emitted from surface seawater into the atmosphere, where they take part in numerous chemical processes such as ozone destruction and the oxidation of mercury and dimethyl sulfide. Here we present oceanic and atmospheric halocarbon data for the Peruvian upwelling zone obtained during the M91 cruise onboard the research vessel METEOR in December 2012. Surface waters during the cruise were characterized by moderate concentrations of bromoform (CHBr3) and dibromomethane (CH2Br2) correlating with diatom biomass derived from marker pigment concentrations, which suggests this phytoplankton group is a likely source. Concentrations measured for the iodinated compounds methyl iodide (CH3I) of up to 35.4 pmol L−1, chloroiodomethane (CH2ClI) of up to 58.1 pmol L−1 and diiodomethane (CH2I2) of up to 32.4 pmol L−1 in water samples were much higher than previously reported for the tropical Atlantic upwelling systems. Iodocarbons also correlated with the diatom biomass and even more significantly with dissolved organic matter (DOM) components measured in the surface water. Our results suggest a biological source of these compounds as a significant driving factor for the observed large iodocarbon concentrations. Elevated atmospheric mixing ratios of CH3I (up to 3.2 ppt), CH2ClI (up to 2.5 ppt) and CH2I2 (3.3 ppt) above the upwelling were correlated with seawater concentrations and high sea-to-air fluxes. During the first part of the cruise, the enhanced iodocarbon production in the Peruvian upwelling contributed significantly to tropospheric iodine levels, while this contribution was considerably smaller during the second part.

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Comprehensive Evaluation of Non-Catalytic Wet Air Oxidation as a Pretreatment to Remove Pharmaceuticals from Hospital Effluents

Environmental Science Water Research & Technology ◽

10.1039/d1ew00203a ◽

2021 ◽

Author(s):

Valérie Boucher ◽

Margot Beaudon ◽

Pedro Ramirez ◽

Pascal Lemoine ◽

Kalyssa Volk ◽

...

Keyword(s):

Surface Waters ◽

Comprehensive Evaluation ◽

Chemical Processes ◽

Catalytic Wet Air Oxidation ◽

Air Oxidation ◽

Wet Air Oxidation ◽

Highly Efficient ◽

Hospital Effluents ◽

Promising Solution

Removal of pharmaceuticals from wastewater using chemical processes is a promising solution to mitigate pollution in drinking and surface waters. Non-catalytic wet air oxidation (WAO) is a highly efficient advanced...

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Environmental control on the variability of DMS and DMSP in the Mauritanian upwelling region

Biogeosciences ◽

10.5194/bg-9-1041-2012 ◽

2012 ◽

Vol 9 (3) ◽

pp. 1041-1051 ◽

Cited By ~ 22

Author(s):

C. Zindler ◽

I. Peeken ◽

C. A. Marandino ◽

H. W. Bange

Keyword(s):

Surface Waters ◽

Coastal Upwelling ◽

Environmental Control ◽

Hot Spot ◽

Local Source ◽

Surface Seawater ◽

Near Surface ◽

Northwest Africa ◽

N:P Ratios ◽

A Minor

Abstract. Dimethylsulphide (DMS) and dissolved and particulate dimethylsulfoniopropionate (DMSPd, DMSPp) were measured in near-surface waters along the Mauritanian coast, Northwest Africa, during the upwelling season in February 2008. DMS, DMSPd and DMSPp surface concentrations of up to 10 nmol L−1, 15 nmol L−1 and 990 nmol L−1, respectively, were measured. However, the DMS concentrations measured are in the low range compared to other upwelling regions. The maximum DMSPp concentration is the highest reported from upwelling regions so far, which might indicate that the Mauritanian upwelling is a hot spot for DMSP. Within the phytoplankton groups, dinoflagellates were identified as important contributors to DMS concentrations, while other algae seemed to have only a minor or no influence on DMS and DMSP concentrations. A pronounced switch from high DMSP to high DMS concentrations was observed when the nitrogen to phosphorus ratio (N:P) was below 7. The high DMS/DMSP ratios at N:P ratios <7 indicate that nitrogen limitation presumably triggered a switch from DMSP to DMS independent of the species composition. Our results underline the importance of coastal upwelling regions as a local source for surface seawater sulphur.

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Standard Molar Enthalpies of Formation of Halomethanes Based on Quantum Chemical Computations

10.26434/chemrxiv.12899432 ◽

2020 ◽

Author(s):

Konstantinos Kalamatianos

Keyword(s):

Gas Phase ◽

Quantum Chemical ◽

Halogen Bond ◽

Chemical Processes ◽

Enthalpies Of Formation ◽

Isodesmic Reaction ◽

Gold Standard Method ◽

Ozone Destruction ◽

Quantum Chemical Computations ◽

Reaction Schemes

Accurate calculations of standard molar enthalpies of formation (ΔΗf°)m(g) and carbon-halogen bond dissociation enthalpies, BDE, of a variety of halomethanes with relevance on several atmospheric chemical processes and particularly to ozone destruction, were performed in the gas phase at 298.15 K. The (ΔΗf°)m(g) of the radicals formed through bond dissociations have also been computed. Ab initio computational methods and isodesmic reaction schemes were used. It is found that for the large majority of these species, the gold standard method of quantum chemistry (CCSD(T)) and even MP2 are capable to predict enthalpy values nearing chemical accuracy provided that isodesmic reaction schemes are used. New estimates for standard molar enthalpies of formation and BDE are suggested including for species that to our knowledge there are no experimental (ΔΗf°)m(g) (CHCl2Br, CHBr2Cl, CHBrCl, CHICl, CHIBr) or BDE values (CHCl2Br, CHBr2Cl, CHBrCl, CHICl, CHIBr) available in the literature. The method and calculational procedures presented may profitably be used to obtain accurate (ΔΗf°)m(g) and BDE values for these species.

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Third Revision of the Global Surface Seawater Dimethyl Sulfide Climatology (DMS-Rev3)

10.5194/essd-2021-236 ◽

2021 ◽

Author(s):

Shrivardhan Hulswar ◽

Rafel Simo ◽

Martí Galí ◽

Thomas Bell ◽

Arancha Lana ◽

...

Keyword(s):

Regional Differences ◽

Dimethyl Sulfide ◽

Measurement Techniques ◽

Fold Increase ◽

Surface Seawater ◽

High Concentration ◽

Concentration Data ◽

Bottom Up ◽

High Productivity ◽

Global Surface

Abstract. This paper presents an updated estimation of the bottom-up global surface seawater dimethyl sulfide (DMS) climatology. This update, called DMS-Rev3, is the third of its kind and includes five significant changes from the last climatology, ‘L11’ (Lana et al., 2011) that was released about a decade ago. The first change is the inclusion of new observations that have become available over the last decade, creating a database of 872,427 observations leading to a ~18-fold increase in raw data as compared to the last estimation The second is significant improvements in data handling, processing, and filtering, to avoid biases due to different observation frequencies which results from different measurement techniques. Thirdly, we incorporate the dynamic seasonal changes observed in the geographic boundaries of the ocean biogeochemical provinces. The fourth change involves the refinement of the interpolation algorithm used to fill in the missing data. And finally, an upgraded smoothing algorithm based on observed DMS variability length scales (VLS) helps to reproduce a more realistic distribution of the DMS concentration data. The results show that DMS-Rev3 estimates the global annual mean DMS concentration to be ~1.87 nM (2.35 nM without a sea-ice mask), i.e., about 4 % lower than the previous bottom-up ‘L11’ climatology. However, significant regional differences of more than 100 % as compared to L11 are observed. The global sea to air flux of DMS is estimated at ~27 TgS yr−1 which is about 4 % lower than L11, although, like the DMS distribution, large regional differences were observed. The largest changes are observed in high concentration regions such as the polar oceans, although oceanic regions that were under-sampled in the past also show large differences between revisions of the climatology. Finally, DMS-Rev3 reduces the previously observed patchiness in high productivity regions.

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Observational evidence for the formation of ocean DMS-derived aerosols during Arctic phytoplankton blooms

10.5194/acp-2016-1161 ◽

2017 ◽

Author(s):

Ki-Tae Park ◽

Sehyun Jang ◽

Kitack Lee ◽

Young Jun Yoon ◽

Min-Seob Kim ◽

...

Keyword(s):

Dimethyl Sulfide ◽

Phytoplankton Bloom ◽

The Arctic ◽

Size Distributions ◽

Particle Size Distributions ◽

Phytoplankton Blooms ◽

Mixing Ratios ◽

Arctic Haze ◽

Aerosol Particle Size ◽

Arctic Atmosphere

Abstract. The connection between marine biogenic dimethyl sulfide (DMS) and the formation of aerosol particles in the Arctic atmosphere was evaluated by analyzing atmospheric DMS mixing ratios, aerosol particle size distributions and aerosol chemical composition data that were concurrently collected at Ny-Ålesund, Svalbard (78.5° N, 11.8° E) during April and May 2015. Measurements of aerosol sulfur (S) compounds showed distinct patterns during periods of Arctic haze (April) and phytoplankton blooms (May). Specifically, during the phytoplankton bloom period the contribution of DMS-derived SO42− to the total aerosol SO42− increased by 7-fold compared with that during the proceeding Arctic haze period, accounting for up to 70 % of fine SO42− particles (

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Underway seawater and atmospheric measurements of volatile organic compounds in the Southern Ocean

Biogeosciences ◽

10.5194/bg-17-2593-2020 ◽

2020 ◽

Vol 17 (9) ◽

pp. 2593-2619 ◽

Cited By ~ 2

Author(s):

Charel Wohl ◽

Ian Brown ◽

Vassilis Kitidis ◽

Anna E. Jones ◽

William T. Sturges ◽

...

Keyword(s):

Volatile Organic Compounds ◽

Southern Ocean ◽

Organic Compounds ◽

Dimethyl Sulfide ◽

Ambient Air ◽

Atmospheric Measurements ◽

Mixing Ratios ◽

Volatile Organic ◽

Air Mixing ◽

Net Flux

Abstract. Dimethyl sulfide and volatile organic compounds (VOCs) are important for atmospheric chemistry. The emissions of biogenically derived organic gases, including dimethyl sulfide and especially isoprene, are not well constrained in the Southern Ocean. Due to a paucity of measurements, the role of the ocean in the atmospheric budgets of atmospheric methanol, acetone, and acetaldehyde is even more poorly known. In order to quantify the air–sea fluxes of these gases, we measured their seawater concentrations and air mixing ratios in the Atlantic sector of the Southern Ocean, along a ∼ 11 000 km long transect at approximately 60∘ S in February–April 2019. Concentrations, oceanic saturations, and estimated fluxes of five simultaneously sampled gases (dimethyl sulfide, isoprene, methanol, acetone, and acetaldehyde) are presented here. Campaign mean (±1σ) surface water concentrations of dimethyl sulfide, isoprene, methanol, acetone, and acetaldehyde were 2.60 (±3.94), 0.0133 (±0.0063), 67 (±35), 5.5 (±2.5), and 2.6 (±2.7) nmol dm−3 respectively. In this dataset, seawater isoprene and methanol concentrations correlated positively. Furthermore, seawater acetone, methanol, and isoprene concentrations were found to correlate negatively with the fugacity of carbon dioxide, possibly due to a common biological origin. Campaign mean (±1σ) air mixing ratios of dimethyl sulfide, isoprene, methanol, acetone, and acetaldehyde were 0.17 (±0.09), 0.053 (±0.034), 0.17 (±0.08), 0.081 (±0.031), and 0.049 (±0.040) ppbv. We observed diel changes in averaged acetaldehyde concentrations in seawater and ambient air (and to a lesser degree also for acetone and isoprene), which suggest light-driven production. Campaign mean (±1σ) fluxes of 4.3 (±7.4) µmol m−2 d−1 DMS and 0.028 (±0.021) µmol m−2 d−1 isoprene are determined where a positive flux indicates from the ocean to the atmosphere. Methanol was largely undersaturated in the surface ocean with a mean (±1σ) net flux of −2.4 (±4.7) µmol m−2 d−1, but it also had a few occasional episodes of outgassing. This section of the Southern Ocean was found to be a source and a sink for acetone and acetaldehyde this time of the year, depending on location, resulting in a mean net flux of −0.55 (±1.14) µmol m−2 d−1 for acetone and −0.28 (±1.22) µmol m−2 d−1 for acetaldehyde. The data collected here will be important for constraining the air–sea exchange, cycling, and atmospheric impact of these gases, especially over the Southern Ocean.

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An integrated sampler for shipboard underway measurement of dimethyl sulfide in surface seawater and air

Atmospheric Environment ◽

10.1016/j.atmosenv.2019.04.022 ◽

2019 ◽

Vol 209 ◽

pp. 86-91 ◽

Cited By ~ 6

Author(s):

Miming Zhang ◽

Wei Gao ◽

Jinpei Yan ◽

Yanfang Wu ◽

Christa A. Marandino ◽

...

Keyword(s):

Dimethyl Sulfide ◽

Surface Seawater

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Draft Genome Sequence of Pelagicola sp. Strain LXJ1103, Isolated from Coastal Surface Seawater

Microbiology Resource Announcements ◽

10.1128/mra.00941-18 ◽

2018 ◽

Vol 7 (14) ◽

Author(s):

Dexi Zhao ◽

Jia Li ◽

Shan Lin ◽

Xuejiao Liang ◽

Xiaopei Lin ◽

...

Keyword(s):

New Species ◽

Genome Sequence ◽

Surface Waters ◽

Draft Genome ◽

Draft Genome Sequence ◽

Surface Seawater ◽

Content Type ◽

The Family ◽

A New Species

Pelagicola sp. strain LXJ1103, a representative of a new species in the family Rhodobacteraceae, was isolated from the coastal surface waters in Xiamen, China.

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