Large seasonal and interannual variations of biogenic sulfur compounds in the Arctic atmosphere (Svalbard; 78.9° N, 11.9° E)

Atmospheric chemistry and physics, Journal Year: 2021, Volume and Issue: 21(12), P. 9761 - 9777

Published: June 29, 2021

Abstract. Seasonal to interannual variations in the concentrations of sulfur aerosols (< 2.5 µm diameter; non sea-salt sulfate: NSS-SO42-; anthropogenic Anth-SO42-; biogenic Bio-SO42-; methanesulfonic acid: MSA) Arctic atmosphere were investigated using measurements chemical composition collected at Ny-Ålesund, Svalbard (78.9∘ N, 11.9∘ E) from 2015 2019. In all measurement years concentration NSS-SO42- was highest during pre-bloom period and rapidly decreased towards summer. During we found a strong correlation between (sum Anth-SO42- Bio-SO42-) Anth-SO42-. This because more than 50 % measured this Anth-SO42-, which originated northern Europe subsequently transported haze. Unexpected increases Bio-SO42- (an oxidation product dimethylsulfide: DMS) occasionally period. These probably regions south (the North Atlantic Ocean Norwegian Sea) rather ocean areas proximity Ny-Ålesund. Another DMS is MSA, ratio MSA extensively used estimate total amount DMS-derived aerosol particles remote marine environments. The remained low, primarily greater loss relative suppression condensation gaseous onto already present air masses being northwards distant source (existing particles). addition, low light intensity resulted photochemically activated oxidant species including OH radicals BrO; these conditions favored pathway acted lower peaked May or June positively correlated with phytoplankton biomass Greenland Barents seas around Svalbard. As result, mean (0.09 ± 0.07) but high (0.32 0.15) bloom post-bloom periods. There large variability (i.e., 0.24 0.11 2017, 0.40 0.14 2018, 0.36 2019) associated changes properties existing particles, biological activities surrounding observation site, mass transport patterns. Our results indicate that not conservative tracer for predicting contribution growth newly formed may be much larger periods

Language: Английский

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Sol–Gel Pt-VO₂ Films as Selective Chemoresistive and Optical H₂ Gas Sensors

ACS Applied Materials & Interfaces, Journal Year: 2024, Volume and Issue: 16(42), P. 57558 - 57570

Published: Oct. 11, 2024

In this work, VO

Language: Английский

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Impacts of sectoral, regional, species, and day-specific emissions on air pollution and public health in Washington, DC

Elementa Science of the Anthropocene, Journal Year: 2021, Volume and Issue: 9(1)

Published: Jan. 1, 2021

We present a novel source attribution approach that incorporates satellite data into GEOS-Chem adjoint simulations to characterize the species-specific, regional, and sectoral contributions of daily emissions for 3 air pollutants: fine particulate matter (PM2.5), ozone (O3), nitrogen dioxide (NO2). This is implemented Washington, DC, first 2011, identify urban pollution sources, again 2016, examine response changes in anthropogenic emissions. In contributed an estimated 263 (uncertainty: 130–444) PM2.5- O3-attributable premature deaths 1,120 (391–1795) NO2 attributable new pediatric asthma cases DC. PM2.5 exposure was responsible 90% these deaths. On-road vehicle 51% NO2-attributable 23% pollution-attributable deaths, making it largest contributing individual sector DC’s pollution–related health burden. Regional emissions, originating from Maryland, Virginia, Pennsylvania, were most pollution-related impacts 57% 89% cases. Emissions distant states 34% more wintertime than summertime, occurring parallel with strong westerlies reduced photochemical sink. Emission reductions between 2011 2016 resulted benefits 76 (28–149) fewer 227 (2–617) The sectors decreases energy generation units (26%) on-road vehicles (20%). Decreases mostly due emission (63%). found impact O3, while impacted O3 proportionally PM2.5. method capable capturing sources at spatial temporal scales applicable many environments, globally.

Language: Английский

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Ontogenetic δ15N Trends and Multidecadal Variability in Shells of the Bivalve Mollusk, Arctica islandica

Frontiers in Marine Science, Journal Year: 2021, Volume and Issue: 8

Published: Nov. 2, 2021

Bulk stable nitrogen isotope values of the carbonate-bound organic matrix in bivalve shells (δ 15 N CBOM ) are increasingly used to assess past food web dynamics, track anthropogenic pollution and reconstruct hydrographic changes. However, it remains unresolved if δ also affected by directed ontogenetic trends which can bias ecological environmental interpretations. This very aspect is tested here with modern fossil specimens long-lived ocean quahog, Arctica islandica , collected from different sites water depths NE Atlantic Ocean. As demonstrated, long chronologies show a general decrease through lifetime −0.006‰ per year. The most likely reason for observed decline change type proteins synthesized at stages life, i.e., gradual shift rich strongly fractionating, trophic amino acids during youth toward source adulthood. Aside this trend, distinct seasonal multidecadal variations (ca. 50 60 years; up 2.90‰) were identified. Presumably, latter governed fluctuations nutrient supply mediated Multidecadal Variation (AMV) Meridional Overturning Circulation (AMOC) combined changes nitrate utilization photoautotrophs associated Rayleigh fractionation processes. Findings underline outstanding potential studies ecology, oceanography pollution, but highlight need compound-specific analyses.

Language: Английский

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Halocarbon emissions by selected tropical seaweeds exposed to different temperatures

Phytochemistry, Journal Year: 2021, Volume and Issue: 190, P. 112869 - 112869

Published: July 15, 2021

Language: Английский

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