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

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

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Cooling down the world oceans and the earth by enhancing the North Atlantic Ocean current

SN Applied Sciences ◽

10.1007/s42452-019-1755-y ◽

2019 ◽

Vol 2 (1) ◽

Cited By ~ 1

Author(s):

Julian David Hunt ◽

Andreas Nascimento ◽

Fabio A. Diuana ◽

Natália de Assis Brasil Weber ◽

Gabriel Malta Castro ◽

...

Keyword(s):

Atlantic Ocean ◽

Arctic Ocean ◽

North Atlantic ◽

North Atlantic Ocean ◽

The Arctic ◽

Ocean Current ◽

The North ◽

The Arctic Ocean ◽

Albedo Effect ◽

Arctic Atmosphere

AbstractThe world is going through intensive changes due to global warming. It is well known that the reduction in ice cover in the Arctic Ocean further contributes to increasing the atmospheric Arctic temperature due to the reduction of the albedo effect and increase in heat absorbed by the ocean’s surface. The Arctic ice cover also works like an insulation sheet, keeping the heat in the ocean from dissipating into the cold Arctic atmosphere. Increasing the salinity of the Arctic Ocean surface would allow the warmer and less salty North Atlantic Ocean current to flow on the surface of the Arctic Ocean considerably increasing the temperature of the Arctic atmosphere and release the ocean heat trapped under the ice. This paper argues that if the North Atlantic Ocean current could maintain the Arctic Ocean ice-free during the winter, the longwave radiation heat loss into space would be larger than the increase in heat absorption due to the albedo effect. This paper presents details of the fundamentals of the Arctic Ocean circulation and presents three possible approaches for increasing the salinity of the surface water of the Arctic Ocean. It then discusses that increasing the salinity of the Arctic Ocean would warm the atmosphere of the Arctic region, but cool down the oceans and possibly the Earth. However, it might take thousands of years for the effects of cooling the oceans to cool the global average atmospheric temperature.

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

10.5194/acp-2020-1270 ◽

2021 ◽

Author(s):

Sehyun Jang ◽

Ki-Tae Park ◽

Kitack Lee ◽

Young Jun Yoon ◽

Kitae Kim ◽

...

Keyword(s):

Sulfur Compounds ◽

The Arctic ◽

Interannual Variations ◽

Arctic Atmosphere ◽

Seasonal And Interannual Variations

Abstract. Seasonal to interannual variations in the concentrations of sulfur aerosols (

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

Atmospheric Chemistry and Physics ◽

10.5194/acp-17-9665-2017 ◽

2017 ◽

Vol 17 (15) ◽

pp. 9665-9675 ◽

Cited By ~ 23

Author(s):

Ki-Tae Park ◽

Sehyun Jang ◽

Kitack Lee ◽

Young Jun Yoon ◽

Min-Seob Kim ◽

...

Keyword(s):

Dimethyl Sulfide ◽

Phytoplankton Bloom ◽

Aerosol Particles ◽

The Arctic ◽

Mixing Ratio ◽

Phytoplankton Blooms ◽

Bloom Period ◽

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 ratio, aerosol particle size distribution 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, and accounted for up to 70 % of fine SO42− particles (<  2.5 µm in diameter). The results also showed that the formation of submicron SO42− aerosols was significantly associated with an increase in the atmospheric DMS mixing ratio. More importantly, two independent estimates of the formation of DMS-derived SO42− aerosols, calculated using the stable S-isotope ratio and the non-sea-salt SO42− ∕ methanesulfonic acid ratio, respectively, were in close agreement, providing compelling evidence that the contribution of biogenic DMS to the formation of aerosol particles was substantial during the Arctic phytoplankton bloom period.

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

10.5194/acp-2020-1270-supplement ◽

2021 ◽

Author(s):

Sehyun Jang ◽

Ki-Tae Park ◽

Kitack Lee ◽

Young Jun Yoon ◽

Kitae Kim ◽

...

Keyword(s):

Sulfur Compounds ◽

The Arctic ◽

Interannual Variations ◽

Supplementary Material ◽

Arctic Atmosphere ◽

Seasonal And Interannual Variations

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Lignans of Sesame (Sesamum indicum L.): A Comprehensive Review

Molecules ◽

10.3390/molecules26040883 ◽

2021 ◽

Vol 26 (4) ◽

pp. 883

Author(s):

Mebeaselassie Andargie ◽

Maria Vinas ◽

Anna Rathgeb ◽

Evelyn Möller ◽

Petr Karlovsky

Keyword(s):

Biological Activities ◽

Chemical Properties ◽

Transformation Products ◽

Extensive Literature ◽

Controversial Issues ◽

Sesame Seeds ◽

Historical Texts ◽

Health Promoting ◽

Processed Products

Major lignans of sesame sesamin and sesamolin are benzodioxol--substituted furofurans. Sesamol, sesaminol, its epimers, and episesamin are transformation products found in processed products. Synthetic routes to all lignans are known but only sesamol is synthesized industrially. Biosynthesis of furofuran lignans begins with the dimerization of coniferyl alcohol, followed by the formation of dioxoles, oxidation, and glycosylation. Most genes of the lignan pathway in sesame have been identified but the inheritance of lignan content is poorly understood. Health-promoting properties make lignans attractive components of functional food. Lignans enhance the efficiency of insecticides and possess antifeedant activity, but their biological function in plants remains hypothetical. In this work, extensive literature including historical texts is reviewed, controversial issues are critically examined, and errors perpetuated in literature are corrected. The following aspects are covered: chemical properties and transformations of lignans; analysis, purification, and total synthesis; occurrence in Seseamum indicum and related plants; biosynthesis and genetics; biological activities; health-promoting properties; and biological functions. Finally, the improvement of lignan content in sesame seeds by breeding and biotechnology and the potential of hairy roots for manufacturing lignans in vitro are outlined.

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Green Silver and Gold Nanoparticles: Biological Synthesis Approaches and Potentials for Biomedical Applications

Molecules ◽

10.3390/molecules26040844 ◽

2021 ◽

Vol 26 (4) ◽

pp. 844 ◽

Cited By ~ 2

Author(s):

Andrea Rónavári ◽

Nóra Igaz ◽

Dóra I. Adamecz ◽

Bettina Szerencsés ◽

Csaba Molnar ◽

...

Keyword(s):

Gold Nanoparticles ◽

Biomedical Applications ◽

Biological Activities ◽

Large Body ◽

Chemical Properties ◽

Biological Synthesis ◽

Silver And Gold Nanoparticles ◽

Comprehensive Collection ◽

Synthetic Approaches ◽

Physical And Chemical

The nanomaterial industry generates gigantic quantities of metal-based nanomaterials for various technological and biomedical applications; however, concomitantly, it places a massive burden on the environment by utilizing toxic chemicals for the production process and leaving hazardous waste materials behind. Moreover, the employed, often unpleasant chemicals can affect the biocompatibility of the generated particles and severely restrict their application possibilities. On these grounds, green synthetic approaches have emerged, offering eco-friendly, sustainable, nature-derived alternative production methods, thus attenuating the ecological footprint of the nanomaterial industry. In the last decade, a plethora of biological materials has been tested to probe their suitability for nanomaterial synthesis. Although most of these approaches were successful, a large body of evidence indicates that the green material or entity used for the production would substantially define the physical and chemical properties and as a consequence, the biological activities of the obtained nanomaterials. The present review provides a comprehensive collection of the most recent green methodologies, surveys the major nanoparticle characterization techniques and screens the effects triggered by the obtained nanomaterials in various living systems to give an impression on the biomedical potential of green synthesized silver and gold nanoparticles.

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Impacts of climate change on air pollution levels in the Northern Hemisphere with special focus on Europe and the Arctic

Atmospheric Chemistry and Physics ◽

10.5194/acp-8-3337-2008 ◽

2008 ◽

Vol 8 (12) ◽

pp. 3337-3367 ◽

Cited By ~ 65

Author(s):

G. B. Hedegaard ◽

J. Brandt ◽

J. H. Christensen ◽

L. M. Frohn ◽

C. Geels ◽

...

Keyword(s):

Climate Change ◽

Temperature Increase ◽

Input Data ◽

Transport Model ◽

Chemical Species ◽

The Arctic ◽

Long Range Transport ◽

Oh Radicals ◽

Validation Period ◽

Range Transport

Abstract. The response of a selected number of chemical species is inspected with respect to climate change. The coupled Atmosphere-Ocean General Circulation Model ECHAM4-OPYC3 is providing meteorological fields for the Chemical long-range Transport Model DEHM. Three selected decades (1990s, 2040s and 2090s) are inspected. The 1990s are used as a reference and validation period. In this decade an evaluation of the output from the DEHM model with ECHAM4-OPYC3 meteorology input data is carried out. The model results are tested against similar model simulations with MM5 meteorology and against observations from the EMEP monitoring sites in Europe. The test results from the validation period show that the overall statistics (e.g. mean values and standard deviations) are similar for the two simulations. However, as one would expect the model setup with climate input data fails to predict correctly the timing of the variability in the observations. The overall performance of the ECHAM4-OPYC3 setup as meteorological input to the DEHM model is shown to be acceptable according to the applied ranking method. It is concluded that running a chemical long-range transport model on data from a "free run" climate model is scientifically sound. From the model runs of the three decades, it is found that the overall trend detected in the evolution of the chemical species, is the same between the 1990 decade and the 2040 decade and between the 2040 decade and the 2090 decade, respectively. The dominating impacts from climate change on a large number of the chemical species are related to the predicted temperature increase. Throughout the 21th century the ECHAM4-OPYC3 projects a global mean temperature increase of 3 K with local maxima up to 11 K in the Arctic winter based on the IPCC A2 emission scenario. As a consequence of this temperature increase, the temperature dependent biogenic emission of isoprene is predicted to increase significantly over land by the DEHM model. This leads to an increase in the O3 production and together with an increase in water vapor to an increase in the number of free OH radicals. Furthermore this increase in the number of OH radicals contributes to a significant change in the typical life time of many species, since OH are participating in a large number of chemical reactions. It is e.g. found that more SO42− will be present in the future over the already polluted areas and this increase can be explained by an enhanced conversion of SO2 to SO42−.

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International Arctic Systems for Observing the Atmosphere: An International Polar Year Legacy Consortium

Bulletin of the American Meteorological Society ◽

10.1175/bams-d-14-00145.1 ◽

2016 ◽

Vol 97 (6) ◽

pp. 1033-1056 ◽

Cited By ~ 30

Author(s):

Taneil Uttal ◽

Sandra Starkweather ◽

James R. Drummond ◽

Timo Vihma ◽

Alexander P. Makshtas ◽

...

Keyword(s):

United States ◽

The United States ◽

Satellite Observations ◽

The Arctic ◽

International Polar Year ◽

Network Measurements ◽

International Polar ◽

In Situ Observations ◽

Arctic Atmosphere

Abstract International Arctic Systems for Observing the Atmosphere (IASOA) activities and partnerships were initiated as a part of the 2007–09 International Polar Year (IPY) and are expected to continue for many decades as a legacy program. The IASOA focus is on coordinating intensive measurements of the Arctic atmosphere collected in the United States, Canada, Russia, Norway, Finland, and Greenland to create synthesis science that leads to an understanding of why and not just how the Arctic atmosphere is evolving. The IASOA premise is that there are limitations with Arctic modeling and satellite observations that can only be addressed with boots-on-the-ground, in situ observations and that the potential of combining individual station and network measurements into an integrated observing system is tremendous. The IASOA vision is that by further integrating with other network observing programs focusing on hydrology, glaciology, oceanography, terrestrial, and biological systems it will be possible to understand the mechanisms of the entire Arctic system, perhaps well enough for humans to mitigate undesirable variations and adapt to inevitable change.

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