scholarly journals Distributions of low molecular weight dicarboxylic acids, ketoacids and α-dicarbonyls in the marine aerosols collected over the Arctic Ocean during late summer

2012 ◽  
Vol 9 (11) ◽  
pp. 4725-4737 ◽  
Author(s):  
K. Kawamura ◽  
K. Ono ◽  
E. Tachibana ◽  
B. Charriére ◽  
R. Sempéré
Keyword(s):  
Oxalic Acid ◽  
Arctic Ocean ◽  
Late Summer ◽  
Dicarboxylic Acids ◽  
Water Soluble ◽  
The Arctic ◽  
Marine Atmosphere ◽  
Marine Aerosols ◽  
Δ13c Values ◽  
The Arctic Ocean

Abstract. Oxalic and other small dicarboxylic acids have been reported as important water-soluble organic constituents of atmospheric aerosols from different environments. Their molecular distributions are generally characterized by the predominance of oxalic acid (C2) followed by malonic (C3) and/or succinic (C4) acids. In this study, we collected marine aerosols from the Arctic Ocean during late summer in 2009 when sea ice was retreating. The marine aerosols were analyzed for the molecular distributions of dicarboxylic acids as well as ketocarboxylic acids and α-dicarbonyls to better understand the source of water-soluble organics and their photochemical processes in the high Arctic marine atmosphere. We found that diacids are more abundant than ketoacids and α-dicarbonyls, but their concentrations are generally low (< 30 ng m−3), except for one sample (up to 70 ng m−3) that was collected near the mouth of Mackenzie River during clear sky condition. Although the molecular compositions of diacids are in general characterized by the predominance of oxalic acid, a depletion of C2 was found in two samples in which C4 became the most abundant. Similar depletion of oxalic acid has previously been reported in the Arctic aerosols collected at Alert after polar sunrise and in the summer aerosols from the coast of Antarctica. Because the marine aerosols that showed a depletion of C2 were collected under the overcast and/or foggy conditions, we suggest that a photochemical decomposition of oxalic acid may have occurred in aqueous phase of aerosols over the Arctic Ocean via the photo dissociation of oxalate-Fe (III) complex. We also determined stable carbon isotopic compositions (δ13C) of bulk aerosol carbon and individual diacids. The δ13C of bulk aerosols showed −26.5‰ (range: −29.7 to −24.7‰, suggesting that marine aerosol carbon is derived from both terrestrial and marine organic materials. In contrast, oxalic acid showed much larger δ13C values (average: −20.9‰, range: −24.7‰ to −17.0‰) than those of bulk aerosol carbon. Interestingly, δ13C values of oxalic acid were higher than C3 (av. −26.6‰) and C4 (−25.8‰) diacids, suggesting that oxalic acid is enriched with 13C due to its photochemical processing (aging) in the marine atmosphere.

scholarly journals Distributions of low molecular weight dicarboxylic acids, ketoacids and α-dicarbonyls in the marine aerosols collected over the Arctic Ocean during late summer

2012 ◽  
Vol 9 (8) ◽  
pp. 10121-10148
Author(s):  
K. Kawamura ◽  
K. Ono ◽  
E. Tachibana ◽  
B. Charriére ◽  
R. Sempéré
Keyword(s):  
Oxalic Acid ◽  
Arctic Ocean ◽  
Late Summer ◽  
Dicarboxylic Acids ◽  
Water Soluble ◽  
The Arctic ◽  
Marine Atmosphere ◽  
Marine Aerosols ◽  
Δ13c Values ◽  
The Arctic Ocean

Abstract. Oxalic and other small dicarboxylic acids have been reported as important water-soluble organic constituents of atmospheric aerosols from different environments. Their molecular distributions are generally characterized by the predominance of oxalic acid (C2) followed by malonic (C3) and/or succinic (C4) acids. In this study, we collected marine aerosols from the Arctic Ocean during late summer in 2009 when sea ice is retreated. The marine aerosols were analyzed for the molecular distributions of dicarboxylic acids as well as ketocarboxylic acids and α-dicarbonyls to better understand the source of water-soluble organics and their photochemical processes in the high Arctic marine atmosphere. We found that diacids are more abundant than ketoacids and α-dicarbonyls, but their concentrations are generally low (< 30 ng m−3), except for one sample (up to 70 ng m−3) that was collected near the mouth of Mackenzie River during clear sky condition. Although the molecular compositions of diacids are in general characterized by the predominance of oxalic acid, a depletion of C2 was found in two samples in which C4 became the most abundant. Similar depletion of oxalic acid has previously been reported in the Arctic aerosols collected at Alert after polar sunrise and in the summer aerosols from the coastal Antarctica. Because the marine aerosols that showed a depletion of C2 were observed under the overcast and/or foggy conditions, we suggest that a photochemical decomposition of oxalic acid may have occurred in aqueous phase of aerosols over the Arctic Ocean via the photo dissociation of oxalate-Fe (III) complex. We also determined stable carbon isotopic compositions (δ13C) of bulk aerosol carbon and individual diacids. The δ13C of bulk aerosols showed −26.5‰ (range: −29.7‰ to −24.7‰), suggesting that marine aerosol carbon is derived from both terrestrial and marine organic materials. In contrast, oxalic acid showed much larger δ13C values (average: −20.9‰, range: −24.7‰ to −17.0‰) than those of bulk aerosol carbon. Interestingly, δ13C values of oxalic acid were higher than C3 (av. −26.6‰) and C4 (−25.8‰) diacids, suggesting that oxalic acid is enriched with 13C due to its photochemical processing (aging) in the marine atmosphere.

scholarly journals Organic molecular composition of marine aerosols over the Arctic Ocean in summer: contributions of primary emission and secondary aerosol formation

2012 ◽  
Vol 9 (8) ◽  
pp. 10429-10465
Author(s):  
P. Q. Fu ◽  
K. Kawamura ◽  
J. Chen ◽  
B. Charrière ◽  
R. Sempéré
Keyword(s):  
Organic Carbon ◽  
Arctic Ocean ◽  
Organic Compounds ◽  
Fungal Spores ◽  
Organic Aerosols ◽  
Molecular Composition ◽  
The Arctic ◽  
Marine Aerosols ◽  
Aerosol Formation ◽  
The Arctic Ocean

Abstract. Organic molecular composition of marine aerosol samples collected during the MALINA cruise in the Arctic Ocean was investigated by gas chromatography/mass spectrometry. More than 110 individual organic compounds were determined in the samples and were grouped into different compound classes based on the functionality and sources. The concentrations of total quantified organics ranged from 7.3 to 185 ng m−3 (mean 47.6 ng m−3), accounting for 1.8–11.0% (4.8%) of organic carbon in the marine aerosols. Primary saccharides were found to be dominant organic compound class, followed by secondary organic aerosol (SOA) tracers formed from the oxidation of biogenic volatile organic compounds (VOCs) such as isoprene, α-pinene and β-caryophyllene. Mannitol, the specific tracer for airborne fungal spores, was detected as the most abundant organic species in the samples with a concentration range of 0.052–53.3 ng m−3 (9.2 ng m−3), followed by glucose, arabitol, and the isoprene oxidation products of 2-methyltetrols. Biomass burning tracers such as levoglucosan are evident in all samples with trace levels. On the basis of the tracer-based method for the estimation of fungal-spore OC and biogenic secondary organic carbon (SOC), we estimate that an average of 10.7% (up to 26.2%) of the OC in the marine aerosols was due to the contribution of fungal spores, followed by the contribution of isoprene SOC (mean 3.8%) and α-pinene SOC (2.9%). In contrast, only 0.19% of the OC was due to the photooxidation of β-caryophyllene. This study indicates that primary organic aerosols from biogenic emissions, both from long-range transport of mid-latitude aerosols and from sea-to-air emission of marine organics, as well as secondary organic aerosols formed from the photooxidation of biogenic VOCs are important factors controlling the organic chemical composition of marine aerosols in the Arctic Ocean.

scholarly journals Molecular Distributions and Compound-Specific Stable Carbon Isotopic Compositions of Plant Wax n-Alkanes in Marine Aerosols along a North–South Transect in the Arctic–Northwest Pacific Region

Atmosphere ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 499
Author(s):  
Jung-Hyun Kim ◽  
Jiyeon Park ◽  
Sol-Bin Kim ◽  
Kyung-Hoon Shin ◽  
Sookwan Kim ◽  
...  
Keyword(s):  
Arctic Ocean ◽  
East Asian ◽  
The Arctic ◽  
Northwest Pacific ◽  
Pacific Region ◽  
Marine Aerosols ◽  
Stable Carbon ◽  
Asian Countries ◽  
Northwest Pacific Ocean ◽  
The Arctic Ocean

A geographical source of n-alkanes in marine aerosols was assessed along a North–South transect in the Arctic–Northwest Pacific region. Marine aerosol samples were collected during the ARA08 cruise with the R/V Araon between 28 August and 28 September 2017. We investigated molecular distributions of n-alkanes (homologous series of C16 to C34) and compound-specific stable carbon isotopes (δ13C) of n-C27, n-C29, and n-C31. Unresolved complex mixtures (UCM) showed a latitudinal trend from the Arctic Ocean to the northwest Pacific Ocean, highlighting an increasing influence of the plume of polluted air exported from East Asian countries. The anthropogenic input was further evidenced by high U/R ratios (>5) and low CPI17–23 (0.6–1.4). The occurrence of high molecular weight (HMW) n-alkanes with high CPI27–31 (>3) indicated the biogenic input of terrestrial higher plant leaf waxes in all studied samples. The δ13C of HMW n-alkanes was influenced by both the relative contributions from the C3/C4 plant sources and from fossil fuel combustions. The back-trajectory analyses provided evidence that changes in molecular distributions and δ13C of n-alkanes were due to the long-range atmospheric transport of anthropogenic and biogenic organic materials from North American and East Asian countries to the Arctic Ocean and the remote northwest Pacific Ocean, respectively.

scholarly journals Organic molecular composition of marine aerosols over the Arctic Ocean in summer: contributions of primary emission and secondary aerosol formation

2013 ◽  
Vol 10 (2) ◽  
pp. 653-667 ◽  
Author(s):  
P. Q. Fu ◽  
K. Kawamura ◽  
J. Chen ◽  
B. Charrière ◽  
R. Sempéré
Keyword(s):  
Organic Carbon ◽  
Arctic Ocean ◽  
Organic Compounds ◽  
Fungal Spores ◽  
Organic Aerosols ◽  
Molecular Composition ◽  
The Arctic ◽  
Marine Aerosols ◽  
Aerosol Formation ◽  
The Arctic Ocean

Abstract. Organic molecular composition of marine aerosol samples collected during the MALINA cruise in the Arctic Ocean was investigated by gas chromatography/mass spectrometry. More than 110 individual organic compounds were determined in the samples and were grouped into different compound classes based on the functionality and sources. The concentrations of total quantified organics ranged from 7.3 to 185 ng m−3 (mean 47.6 ng m−3), accounting for 1.8–11.0% (4.8%) of organic carbon in the marine aerosols. Primary saccharides were found to be dominant organic compound class, followed by secondary organic aerosol (SOA) tracers formed from the oxidation of biogenic volatile organic compounds (VOCs) such as isoprene, α-pinene and β-caryophyllene. Mannitol, the specific tracer for airborne fungal spores, was detected as the most abundant organic species in the samples with a concentration range of 0.052–53.3 ng m−3 (9.2 ng m−3), followed by glucose, arabitol, and the isoprene oxidation products of 2-methyltetrols. Biomass burning tracers such as levoglucosan are evident in all samples with trace levels. On the basis of the tracer-based method for the estimation of fungal-spore OC and biogenic secondary organic carbon (SOC), we estimate that an average of 10.7% (up to 26.2%) of the OC in the marine aerosols was due to the contribution of fungal spores, followed by the contribution of isoprene SOC (mean 3.8%) and α-pinene SOC (2.9%). In contrast, only 0.19% of the OC was due to the photooxidation of β-caryophyllene. This study indicates that primary organic aerosols from biogenic emissions, both from long-range transport of mid-latitude aerosols and from sea-to-air emission of marine organics, as well as secondary organic aerosols formed from the photooxidation of biogenic VOCs are important factors controlling the organic chemical composition of marine aerosols in the Arctic Ocean.

Arctic summer sea-ice SAR signatures, melt-season characteristics, and melt-pond fractions

Polar Record ◽  
1997 ◽  
Vol 33 (185) ◽  
pp. 101-112 ◽  
Author(s):  
M. O. Jeffries ◽  
K. Schwartz ◽  
S. Li
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
Late Summer ◽  
Beaufort Sea ◽  
Early Summer ◽  
The Arctic ◽  
Late Winter ◽  
Melt Pond ◽  
Melt Ponds ◽  
The Arctic Ocean

AbstractVariations in multiyear sea-ice backscatter from the synthetic aperture radar (SAR) aboard the ERS-1 satellite are interpreted in terms of melt-season characteristics (onset of melt in spring and of freeze-up in autumn, and the duration of the snow-decay period, the melt season, and the melt-pond season) from late winter to early autumn 1992 in two regions of the Arctic Ocean: the northeastern Beaufort Sea adjacent to the Queen Elizabeth Islands in the Canadian high Arctic and the western Beaufort Sea north of Alaska. In the northeastern Beaufort Sea, the onset of melt occurs later, and the periods of snow-cover decay and the occurrence of melt ponds are shorter than in the western Beaufort Sea. These melt-season characteristics of each area are consistent with previous observations that the northeastern Beaufort Sea has one of the most severe summer climates in the Arctic Ocean. A model, which assumes that the backscatter from multiyear floes is the sum of backscatter from bare ice and melt ponds, is used to derive the melt-pond fraction during the summer. The results show that melt-pond fractions decrease from an early-summer maximum of about 60% to a late-summer minimum around 10%. The magnitude of the melt-pond fractions and their decline during the summer is consistent with previous, more qualitative data. The SAR model, which gives melt-pond fractions with lower variability and less uncertainty than previous data, offers an improved approach to the reliable estimation of the areal extent of water on ice floes. Suggestions for further improvement of the model include accounting for the consequences of wind-speed variations, summer snowfall, and freeze/thaw cycles and their effects on melt-pond and ice-surface roughness.

scholarly journals Influence of synoptic atmospheric conditions on movement of individual sea-ice floes in Fram Strait, late summer 2010

2015 ◽  
Vol 56 (69) ◽  
pp. 445-450
Author(s):  
Jennifer A. King ◽  
Grant R. Bigg ◽  
Richard Hall
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
Late Summer ◽  
The Arctic ◽  
Boreal Summer ◽  
Fram Strait ◽  
Atmospheric Conditions ◽  
Ice Dynamics ◽  
The Arctic Ocean ◽  
Ice Floes

AbstractIn this paper we investigate the effect on sea-ice movement of changes in the synoptic atmospheric conditions in late boreal summer 2010. Our study area is the western Fram Strait, a crucial passage for the transport of ice out of the Arctic basin. Ice dynamics here affect the movement of ice in the East Greenland Current, the transpolar drift and ice extent in the Arctic Ocean. In contrast to other times of the year, when the Fram Strait wind field is characterized by strong, persistent northerlies, we show that the weaker, more variable winds typical during late summer for the Fram Strait can slow movement of ice floes out of the area, thus slowing the export of ice from the Arctic Ocean at the end of summer, a time crucial for ice export. The Arctic Ocean could lose even more of the ice that survives the summer if this was not the case. This would leave the Arctic Ocean in an even more vulnerable position with regard to the amount of multi-year ice remaining the following summer.

Evidence for the uptake of atmospheric acetone and methanol by the Arctic Ocean during late summer DMS-Emission plumes

2012 ◽  
Vol 117 (D12) ◽  
pp. n/a-n/a ◽  
Author(s):  
S. J. Sjostedt ◽  
W. R. Leaitch ◽  
M. Levasseur ◽  
M. Scarratt ◽  
S. Michaud ◽  
...  
Keyword(s):  
Arctic Ocean ◽  
Late Summer ◽  
The Arctic ◽  
The Arctic Ocean

Iodine speciation in marine aerosols along a 15000-km round-trip cruise path from Shanghai, China, to the Arctic Ocean

2010 ◽  
Vol 7 (5) ◽  
pp. 406 ◽  
Author(s):  
Siqi Xu ◽  
Zhouqing Xie ◽  
Bing Li ◽  
Wei Liu ◽  
Liguang Sun ◽  
...  
Keyword(s):  
Arctic Ocean ◽  
Inductively Coupled Plasma ◽  
The Arctic ◽  
Marine Aerosols ◽  
Round Trip ◽  
Inductively Coupled ◽  
Iodine Species ◽  
Iodine Speciation ◽  
The Arctic Ocean ◽  
Plasma Mass Spectrometry

Environmental context.Iodine in the atmosphere plays an important role in troposphere ozone destruction and climate change. However, cycling of atmospheric iodine is still poorly understood because of uncertainties in iodine speciation in aerosols. Here we report iodine levels and speciation in marine aerosols collected along a cruise path from Shanghai to the Arctic Ocean. Abstract.Total iodine (TI) and water-soluble iodine species in the total suspended particle samples collected onboard a round-trip cruise from Shanghai, China to the Arctic Ocean were measured using inductively coupled plasma mass spectrometry and ion chromatography–inductively coupled plasma mass spectrometry respectively. TI and total soluble iodine (TSI) levels varied considerably both spatially and temporally over the length of the voyage. The maximum iodine levels occurred in the Arctic Ocean in September, whereas the minimum levels occurred in the Western and Northern Pacific Ocean in July. Iodate (IO3 –) was found to be the dominant species in most samples, accounting for 57.8% of TSI on average, whereas iodide and soluble organic iodine only accounted for 16.8% of TSI on average. There was also a significant fraction of insoluble iodine. This finding confirms model predictions of atmospheric iodine speciation, i.e. the predominant iodine species is iodate rather than iodide.

Sign in / Sign up

Export Citation Format

Share Document