organic molecular composition of marine aerosols over the ......organic molecular composition of...

Biogeosciences 10 653ndash667 2013wwwbiogeosciencesnet106532013doi105194bg-10-653-2013copy Author(s) 2013 CC Attribution 30 License

Biogeosciences

Organic molecular composition of marine aerosols over the ArcticOcean in summer contributions of primary emission and secondaryaerosol formation

P Q Fu12 K Kawamura2 J Chen3 B Charri ere4 and R Sempere4

1State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of AtmosphericPhysics Chinese Academy of Sciences Beijing 100029 China2Institute of Low Temperature Science Hokkaido University Sapporo 060-0819 Japan3SKLEG Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China4Aix-Marseille Universite Mediterranean Institute of Oceanography (MIO) 13288 Marseille Cedex 9 Universite du SudToulon-Var MIO CNRSINSU MIO UMR 7294 France

Correspondence toP Q Fu (fupingqingmailiapaccn)

Received 30 June 2012 ndash Published in Biogeosciences Discuss 8 August 2012Revised 1 December 2012 ndash Accepted 19 December 2012 ndash Published 1 February 2013

Abstract Organic molecular composition of marine aerosolsamples collected during the MALINA cruise in the ArcticOcean was investigated by gas chromatographymass spec-trometry More than 110 individual organic compounds weredetermined in the samples and were grouped into differentcompound classes based on the functionality and sourcesThe concentrations of total quantified organics ranged from73 to 185 ng mminus3 (mean 476 ng mminus3) accounting for 18ndash110 (48 ) of organic carbon in the marine aerosols Pri-mary saccharides were found to be dominant organic com-pound class followed by secondary organic aerosol (SOA)tracers formed from the oxidation of biogenic volatile or-ganic compounds (VOCs) such as isopreneα-pinene andβ-caryophyllene Mannitol the specific tracer for airbornefungal spores was detected as the most abundant organicspecies in the samples with a concentration range of 0052ndash533 ng mminus3 (92 ng mminus3) followed by glucose arabitol andthe isoprene oxidation products of 2-methyltetrols Biomassburning tracers such as levoglucosan are evident in all sam-ples with trace levels On the basis of the tracer-based methodfor the estimation of fungal-spore OC and biogenic sec-ondary organic carbon (SOC) we estimate that an averageof 107 (up to 262 ) of the OC in the marine aerosolswas due to the contribution of fungal spores followed bythe contribution of isoprene SOC (mean 38 ) andα-pineneSOC (29 ) In contrast only 019 of the OC was due to

the photooxidation ofβ-caryophyllene This study indicatesthat primary organic aerosols from biogenic emissions bothfrom long-range transport of mid-latitude aerosols and fromsea-to-air emission of marine organics as well as secondaryorganic aerosols formed from the photooxidation of biogenicVOCs are important factors controlling the organic chemicalcomposition of marine aerosols in the Arctic Ocean

1 Introduction

Organic aerosols are ubiquitous in the marine atmosphereGiven the oceanrsquos extension marine organic aerosols havereceived increasing attention because they constitute one ofthe most important natural aerosol systems at a global level(OrsquoDowd and de Leeuw 2007 Langmann et al 2008) Ma-rine organic aerosols play major roles in the environmentalissues related to global and regional climate chemistry of theatmosphere and biogeochemical cycling of nutrients such ascarbon and nitrogen (OrsquoDowd and de Leeuw 2007) For ex-ample they influence solar irradiation directly by backscat-tering solar irradiation and indirectly by forming cloud con-densation nuclei (CCN) (Meskhidze and Nenes 2006)

To fully understand the sources and molecular com-position of marine organic aerosols is necessary to eval-uate their impacts on climate Marine organic aerosols

Published by Copernicus Publications on behalf of the European Geosciences Union

654 P Q Fu et al Organic aerosols over the Arctic Ocean

comprise primary organic aerosol (POA) and secondary or-ganic aerosol (SOA) Primary marine organic aerosols canbe produced from the interaction of wind with the ocean sur-face and results in the mechanical production of sea sprayaerosols (Rinaldi et al 2010) The best-known precursor ofmarine POA is dimethyl sulphide (DMS) that is producedbiogenically in the ocean Sea spray aerosols are assumed toenrich in organic matter when the marine surface is charac-terized by high biological activities (OrsquoDowd et al 2004)A recent study (Schmitt-Kopplin et al 2012) provides ev-idence that marine surface water via bubble bursting pro-cesses can produce a significant fraction of primary organicaerosols that typically contain homologous series of oxo-hydroxy- methoxy- branched fatty acids and mono- di- andtricarboxylic acids as well as monoterpenes and sugars

The atmospheric oxidation of volatile organic compounds(VOCs) emitted from the ocean can form SOA (OrsquoDowdand de Leeuw 2007) Traditionally the most studied SOAcomponent in the marine boundary layer (MBL) is methane-sulfonic acid (MSA) which is formed from the oxidationof DMS Other components such as organosulfates (sulfateesters of C9ndashC13 hydroxyl carboxylic acids) can be consid-ered as marine SOA tracers for the oxidation of unsaturatedfatty acids derived from marine algae (Claeys et al 2010)Meskhidze and Nenes (2006) proposed that SOA formationfrom the oxidation of phytoplankton-derived isoprene can af-fect the chemical composition of marine CCN and influencecloud droplet number Laboratory experiments (Ekstrom etal 2009) have shown that 2-methyltetrols tracers for iso-prene SOA (Claeys et al 2004) and related isoprene oxida-tion products can increase CCN levels in the pristine marineatmosphere that is limited in CCN In addition to the oceanicemission of isoprene recent shipboard measurements overthe South Atlantic Ocean have provided the evidence for ma-rine production of monoterpenes (Yassaa et al 2008) How-ever recent modeling studies suggested that the oceanic iso-prene and monoterpene sources are not significant enoughto control marine organic aerosols (Spracklen et al 2008Arnold et al 2009 Gantt et al 2009 Anttila et al 2010)For example Myriokefalitakis et al (2010) proposed thatthe annual global marine SOA from isoprene and monoter-pene oxidation was minor (01 Tg yrminus1) compared to thosefrom the oxidation of DMS (4 Tg yrminus1) and marine amines(1 Tg yrminus1)

Despite considerable advances in primary and secondarymarine aerosol studies during the last decade the chemi-cal nature of marine organic aerosols remains poorly under-stood due to their diverse sources and formation mechanisms(OrsquoDowd and de Leeuw 2007) Marine organic aerosolsare influenced not only by oceanic emissions of primaryaerosols and SOA precursors but also by continental emis-sions through long-range atmospheric transport So far fieldmeasurements concerning organic molecular compositionsof marine aerosols are limited (eg Simoneit et al 1991Simoneit et al 2004b Fu et al 2011) In particular lit-

tle is known about the abundances of biogenic SOA trac-ers from the oxidation of isoprene (eg 2-methyltetrols) andαβ-pinene (eg pinonic and pinic acids) in the MBL (Fu etal 2011) especially in the polar regions During the polarsunrise season the Arctic atmosphere can serve as a uniquephotochemical reactor influenced by marine-derived parti-cles from the Arctic Ocean and continent-derived particlesand their precursors from the mid-latitudes in Eurasia orNorth America (Barrie 1986 Quinn et al 2007) Duringsummer the Arctic atmosphere is isolated from lower lati-tudes by the polar front (Iziomon et al 2006) Because cli-mate change is proceeding fastest in the high latitudes (Lawand Stohl 2007) and the Arctic Ocean waters could be animportant source of Arctic aerosols in summer there is anincreasing demand for better understanding the molecularcharacteristics and the sources of biogenic POA and SOAin the summertime Arctic atmosphere

The objective of this study is to investigate the chemi-cal speciation of both POA and SOA in the MBL over thesouthern Beaufort Sea Canadian Arctic More than 110 or-ganic compounds including aliphatic lipids anhydrosugarsprimary saccharides lignin and resin acids aromatic acidspolyacids sterols as well as polar organic tracer (eg 2-methyltetrols pinic acid andβ-caryophyllinic acid) for thephotooxidation of biogenic VOCs have been detected in themarine aerosols Their possible sources formation processesand the contributions of different organic compounds to or-ganic carbon (OC) are also discussed

2 Materials and methods

21 Sample collection

The FrancendashCanadandashUSA joint Arctic campaign MALINAwas conducted in the southern Beaufort Sea Canadian Arc-tic in summer 2009 Total suspended particulate (TSP) sam-ples (n = 10) were collected on a twondashthree day basis us-ing a high volume air sampler (Kimoto AS-810B) aboardthe icebreaker CCGSAmundsenon 3ndash25 August 2009 Onefield blank filter was performed by placing it in the samplerfor less than one minute without turning on the pump Allsamples were collected onto pre-combusted (450C for 6 h)quartz fiber filters (20times 25 cm Pallflex 2500QAT-UP) Thepump of the air sampler was switched onoff using a windspeed (gt5 m sminus1) and wind sector (plusmn 60deg) controller systemto avoid any potential contamination from the ship exhaustBefore the sampling filter was placed in a pre-combusted(450C for 6 h) glass jar with a Teflon-lined cap during thetransport and storage After the sampling the filter was re-covered into the glass jar transported to the laboratory andstored atminus20C prior to analysis

Biogeosciences 10 653ndash667 2013 wwwbiogeosciencesnet106532013

P Q Fu et al Organic aerosols over the Arctic Ocean 655

22 Extraction and derivatization

For each sample a filter aliquot (ca 25 cm2) wascut into pieces and extracted three times withdichloromethanemethanol (21 vv) under ultrasonicationfor 10 min The solvent extracts were filtered through quartzwool packed in a Pasteur pipette concentrated by the use ofa rotary evaporator and then blown down to dryness withpure nitrogen gas The extracts were then reacted with 50 microLof NO-bis-(trimethylsilyl)trifluoroacetamide (BSTFA) with1 trimethylsilyl chloride and 10 microL of pyridine at 70Cfor 3 h After reaction the derivatives were diluted by theuse of 140 microL ofn-hexane with 143 ng microLminus1 of the internalstandard (C13 n-alkane) prior to gas chromatographymassspectrometry (GCMS) injection

23 Gas chromatographymass spectrometry

GCMS analyses were performed on a Hewlett-Packardmodel 6890 GC coupled to Hewlett-Packard model 5973mass-selective detector (MSD) The GC was equipped witha splitsplitless injection and a DB-5MS fused silica cap-illary column (30 mtimes 025 mm in diameter 025 microm filmthickness) with the GC oven temperature programmed from50C (2 min) to 120 degC at 15C minminus1 and then to 300Cat 5C minminus1 with a final isotherm hold at 300C for16 min Helium was used as the carrier gas at a flow rate of10 mL minminus1 The sample was injected on a splitless modewith the injector temperature at 280C The mass spectrome-ter was operated in the electron ionization (EI) mode at 70 eVand scanned in themzrange 50ndash650 Data were acquired andprocessed with the ChemStation software GCMS responsefactors were determined using authentic standards For somebiogenic SOA tracers whose standards are not commerciallyavailable their concentrations were estimated by some sur-rogates (Fu et al 2010) Recovery experiments were per-formed by spiking a certain amount of authentic standardsonto pre-combusted quartz fiber filters and were analyzedlike real samples Recoveries of all the standards were bet-ter than 80 expect for polyacids and pinonic acid whoserecoveries were around 60 (Fu et al 2009a 2010) Thefield and the laboratory blank filters were also analyzed bythe procedure described above for quality assurance The re-sults showed contamination levels are less than 5 of realsamples for any species detected All the data reported herewere corrected for the field blank

24 Analysis for OC

Organic carbon (OC) and elemental carbon (EC) were de-termined using a Sunset Lab carbon analyzer following theInteragency Monitoring of Protected Visual Environments(IMPROVE) thermal evolution protocol and assuming car-bonate carbon in the sample to be negligible (Wang et al2005a) In brief an aliquot (814 mm) of quartz fiber filter

was punched for each sample The punched filter was placedin a quartz boat inside the thermal desorption chamber of theanalyzer and then stepwise heating was applied The ana-lytical errors in triplicate analysis were within 10 and thelimits of detection (LOD) were 02 microg cmminus2 for both OC andEC The levels of EC in the samples were generally belowthe LOD and thus were not reported here

3 Results and discussion

31 Meteorological conditions and air-mass backtrajectory analysis

During sample collection the ambient temperatures rangedfrom minus15C to 92C with an average of 30C Theweather conditions during the cruise were mostly cloudyand occasionally foggy with rare sunny conditions (Ta-ble 1) while there were no rainsnow events during thesampling period In order to determine where troposphericair arrived to the ship during sampling periods for eachaerosol sample air-mass back trajectory analyses were con-ducted using the NOAA Hybrid Single-Particle LagrangianIntegrated Trajectory (HYSPLIT) model (httpwwwarlnoaagovreadyhysplit4html) The trajectories were calculatedfrom the start-to-end points every 3 h of each sampling pe-riod at altitudes of 50 100 and 200 m As shown in Fig 1 airmasses mostly came from the west and then passed over theArctic Ocean to the ship during 3ndash11 August when the sam-ples of QFF3352 QFF3354 and QFF3355 were collectedQFF3358-3360 also showed similar trajectories which weremainly from the west direction However QFF3356 andQFF3357 as well as the last two samples (QFF3361 andQFF3362) were collected when the air masses mainly origi-nated from the northeast east and southeast directions Thisis especially true for the last sample (QFF3362) whichshowed air masses were transported from northern Canadaindicating an influence of continental aerosols

32 Organic compounds

Homologues of ten organic compound classes ien-alkanes fatty acids fatty alcohols sugar compounds ligninand resin acids sterols phthalate esters hydroxy-polyacidsaromatic acids and biogenic SOA tracers were detected inthe marine aerosols with total concentration ranges of 73ndash185 ng mminus3 (mean 476 ng mminus3) Table S1 presents the con-centrations of more than 110 organic compounds detectedin this study Figure 2 shows a typical GCMS trace (To-tal Ion Current TIC) for the major resolved organic compo-nents of total aerosol extracts Among the identified organiccompounds sugar compounds fatty acids and biogenic SOAtracers are the major compound classes while the others arerelatively minor (Fig 3) Mannitol a specific tracer for air-borne fungal spores was (on average) found to be the mostabundant single compound followed by glucose arabitol

wwwbiogeosciencesnet106532013 Biogeosciences 10 653ndash667 2013


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Sample ID Back trajectories

QFF3352

QFF3354

QFF3355

QFF3356

QFF3357

QFF3358

QFF3359

QFF3360

QFF3361

QFF3362

Cruise tracks

Sample ID

160oW 140 120 100 821 822

Figure 1 Five-day air mass back trajectories for each sample collected in the Southern 823

Beaufort Sea Canadian Arctic during the MALINA campaign are shown in the left side 824

cruise tracks are present in red Enlarged cruise tracks for each sample are shown in the right 825

side 826

827

Fig 1 Five-day air mass back trajectories for each sample collected in the southern Beaufort Sea Canadian Arctic during the MALINAcampaign are shown on the left side cruise tracks are presented in red Enlarged cruise tracks for each sample are shown on the right side

and di-(2-ethylhexyl)phthalate (Table S1) such a pattern isdifferent from those reported in urban aerosols (eg Wang etal 2006) which were dominated by biomass burning tracersand phthalates

Generally much higher levels of organics were found inthe middle (13ndash15 August QFF3357) and at the end (23ndash25August QFF3362) of the campaign (Fig 3) than other peri-ods This trend is similar to the temporal variations of OCcontents (Table 1) and dicarboxylic acids in the same sam-ple set (Kawamura et al 2012) OC in the marine aerosolsranged from 011ndash293 microgC mminus3 (mean 056 microgC mminus3) be-ing in accordance with those (011ndash14 microgC mminus3) reported inthe northern Indian Ocean (Neususzlig et al 2002) and those(006ndash17 microgC mminus3 mean 058 microgC mminus3) in marine aerosolscollected during a round-the-world cruise in the low to mid-latitudes in the Northern Hemisphere (Fu et al 2011) Thehighest level of OC was found in QFF3357 (293 ng mminus3)

that was collected near the seashore (Table 1 and Fig 1)suggesting a terrestrial input QFF3362 also contained a rel-atively high level of OC

321 Biomass burning tracers

Biomass burning is an important source of atmospheric gasesand particles on a regional and global scale In the Arcticregion biomass-burning aerosols are enhanced in winterndashspring due to long-range atmospheric transport from mid-latitudes in Eurasia and North America (Stohl et al 2007 Fuet al 2009a) A recent aircraft observation of forest fires inthe Siberia in summer found that the fire plumes can transporttoward the Arctic (Paris et al 2009) Levoglucosan which isproduced in large quantities during pyrolysis of cellulose isconsidered as a key tracer for biomass burning (Simoneit2002) In the present study concentrations of levoglucosanranged from 001 to 093 ng mminus3 (037 ng mminus3) representing



30

828

829

Figure 2 A typical GCMS trace (total ion current TIC) for a total extract (TMS derivatized) 830

of the aerosol sample (QFF3362) collected in the Arctic Ocean For abbreviations see Table 831

S1 832 833

Fig 2A typical GCMS trace (total ion current TIC) for a total extract (trimethylsilyl (TMS) derivatized) of the aerosol sample (QFF3362)collected in the Arctic Ocean For abbreviations see Table S1

Table 1 Bulk and organic molecular data for marine aerosol samples collected during the MALINA cruise in 2009 Concentrations fororganic species are presented in ng mminus3

Sample Sample Sample Cloud Origin Chla OC n-Alkanes n-Fatty acids n-AlcoholsNo ID periods covera of air massb (microg Lminus1) (ug mminus3) LMW HMW LMW HMW LMW HMW Levod Mannitole 2-MTf

(C18minus24) (C25minus34) CPI c (C8minus23) (C24minus32) C18nC180 (C12minus23) (C24minus30)

1 QFF3352 3ndash5 Aug MC-O AKAO 040plusmn 023 030 005 017 19 087 016 05 027 016 067 32 0182 QFF3354 5ndash8 Aug MC-O fog AO 197plusmn 374 036 017 047 16 23 033 02 11 028 093 005 0313 QFF3355 8ndash11 Aug MC-O AO 009plusmn 0035 036 019 033 17 15 019 01 076 018 067 013 0214 QFF3356 11ndash13 Aug MC-O NC 146plusmn 134 025 015 029 23 28 013 14 29 070 014 17 0575 QFF3357 13ndash15 Aug MC-O fog NCAO 164plusmn 133 293 11 34 15 107 12 18 53 31 033 533 1226 QFF3358 15ndash17 Aug PC-O AO 098plusmn 100 011 007 006 17 086 003 09 11 011 006 029 0207 QFF3359 17ndash19 Aug O AO 0075plusmn 0003 023 004 014 17 089 005 13 033 019 001 40 0158 QFF3360 19ndash21 Aug MC-O AO 0072plusmn 002 020 006 008 18 14 006 08 046 073 002 50 0069 QFF3361 21ndash23 Aug C-O NCAO ndash 025 007 017 21 20 011 06 055 099 003 86 03710 QFF3362 23ndash25 Aug O fog NC 011plusmn 004 065 034 080 70 94 095 39 40 30 080 155 284

a C clear (gt0 to 5 ) PC partly cloudy (5 to 50 ) MC mostly cloudy (50 to 95 ) O overcast (95ndash100 )b Primary source regions for air-mass back trajectories Arctic Ocean (AO) Alaska (AK) northern Canada (NC)c CPI carbon preference index (C21+C23+C25+C27+C29+C31+C33)(C22+C24+C26+C28+C30+C32+C34) for n-alkanesd Levo levoglucosan a biomass-burning tracer (Simoneit 2002)e Mannitol a fungal-spore tracer (Bauer et al 2008)f 2-MT 2-methyltetrols the sum of 2-methylthreitol and 2-methylerythritol which are isoprene SOA tracers (Claeys et al 2004)

a background level over the southern Beaufort Sea CanadianArctic These values are similar to those (0003ndash11 ng mminus3)

found in the Canadian high Arctic aerosols collected at Alert(Fu et al 2009a) where the level of levoglucosan was foundto be higher in winter than in spring The isomers of levoglu-cosan galactosan and mannosan were also detected in thesamples (Table S1) These anhydrosugars were also detectedin aerosols collected over the open oceans (Fu et al 2011)Such a low level of levoglucosan in the marine aerosols overthe Arctic Ocean should be explained by both wetdry depo-sitions and atmospheric dilution of aerosol particles duringlong-range transport Further levoglucosan may be possiblyremoved by photodegradation through the reaction with freeradicals such as OH (Hoffmann et al 2010)

Dehydroabietic acid a specific biomass-burning tracer ofconifer resin is often detected in urban rural and marineaerosols (Simoneit et al 2004b Fu et al 2011) The concen-

tration ranges of dehydroabietic acid were 002ndash065 ng mminus3

with an average of 014 ng mminus3 These values are higher thanthose (0002ndash0033 ng mminus3) in the high Arctic aerosols thatwere collected during winterndashspring (Fu et al 2009a) Thissuggests that the influence of wildfires in the boreal coniferforests in Siberia and North America on the Arctic atmo-sphere may be more important during summerndashautumn thanwinterndashspring Lignin is a wood polymer and upon burningyields phenolic acids 4-Hydroxybenzoic acid is produced byburning of grasses and other non-woody vegetation whereasvanillic acid is produced from both softwood and hard-wood (Simoneit 2002) 34-Dihydroxybenzoic acid (proto-catechuic acid) is an antioxidant that contains a polyphenolicstructure These phenolic compounds have been reported insmoke particles and ambient aerosols (Simoneit 2002) Theywere detected at trace levels in the present study (Table S1)which are 1ndash2 orders of magnitude lower than those reported



31

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3357

QFF

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QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n (n

g m

-3)

834 835

Figure 3 Chemical compositions of organic compounds in the summertime marine aerosols 836

collected during the MALINA campaign 837

838

Fig 3 Chemical compositions of organic compounds in the sum-mertime marine aerosols collected during the MALINA campaign

in coastal marine aerosols (05ndash90 ng mminus3) (Simoneit et al2004b)

βminusSitosterol was also detected in the summertime ma-rine aerosols over the Arctic Ocean ranging from 0017 to069 ng mminus3 with an average of 015 ng mminus3 It is present inall vegetation and can be emitted into the atmosphere viabiomass burning (Simoneit 2002)β-Sitosterol was previ-ously reported in marine aerosols from the western North Pa-cific during the 1991 El Nino forest fire event that occurred inIndonesia (Kawamura et al 2003) In general relatively lowlevels of levoglucosan dehydroabietic acidβ-sitosterol andother lignin acids indicate that the contribution of biomassburning to the summertime Arctic aerosols should be minor

322 Aliphatic lipids

n-alkanes (C18ndashC34) showed carbon number maxima (Cmax)

at C27 with weak oddeven carbon number predominance(carbon preference index CPI ranging from 15 to 23) ex-cept the last sample (QFF3362) that showed CPI up to 70(Table S1) CPI value is close to unity in anthropogenicsources (eg petroleum) while it is around 10 in terres-trial higher plant waxes Our results demonstrate that themarine aerosols studied were mainly influenced by fossilfuel combustion except for the last sample which was morelikely affected by higher plant waxes However polycyclicaromatic hydrocarbons (PAHs) and hopanes which are spe-cific tracers for fossil fuel combustion were not detectablein this study Concentrations ofn-alkanes (C18ndashC34) rangedfrom 014 to 45 ng mminus3 High molecular weight (HMW)n-alkanes (C25ndashC34) were up to 34 ng mminus3 in QFF3357 fol-lowed by QFF3362 (080 ng mminus3) suggesting an input ofterrestrial higher plant leaf waxes (Eglinton and Hamilton1967)

A homologous series of saturated fatty acids (C8ndashC32)

were detected in the samples Except for C9 which isan oxidation product of oleic acid (C181) (Kawamura andGagosian 1987) a strong even carbon number predomi-nance was observed (CPI=19ndash80 for C20ndashC32) with Cmaxat C16 (Table S1) HMW fatty acids (geC24) are derived fromterrestrial higher plant waxes while low molecular weight(LMW) fatty acids (leC23) have multiple sources such as vas-cular plants microbes and marine phytoplankton (Simoneitand Mazurek 1982 Rogge et al 1993 Kawamura et al2003) For example during the MALINA campaign Rontaniet al (2012) found that the total lipid extracts of sinking par-ticles collected across the Canadian Beaufort shelf exhibiteda distribution of even-carbon number dominated fatty acidsranging from C14 to C24 The abundances of LMW fattyacids down to C8 were found in the present study being sim-ilar to those found in the Canadian high Arctic aerosols atAlert (Fu et al 2009a) Such a pattern should be caused bythe shift in gasparticle partitioning of LMW fatty acids dueto lower ambient temperature in the Arctic than in warmerregions

In a previous study Fu et al (2009a) found that alkenoicacids (eg C181) were not detected in the high Arcticaerosols in winterndashspring They suggested that the Arcticaerosols were already aged during long-range atmospherictransport from middle latitudes to the Arctic Interestinglyunsaturated fatty acids (C181 and C182) were detected inall the marine aerosols over the Arctic Ocean in summerThey are major constituents of cell membranes in marinephytoplankton and terrestrial plants and can emit into theatmosphere directly from leaf surfaces of plants as wellas wood combustion (Fine et al 2001) Oleic (C181) andlinoleic (C182) acids are unstable and undergo photochem-ical degradation in the marine atmosphere (Kawamura andGagosian 1987) and thus have not frequently been detectedin remote marine aerosols (Simoneit 1977 Kawamura andGagosian 1987 Bendle et al 2007) Bendle et al (2007)proposed that the ratio of the unsaturatedsaturated C18 fattyacids (C18nC180) could be a qualitative guide to the rela-tive freshness of the organic matter in marine aerosol sam-ples Higher ratios of C18nC180 were found in samplesassociated with proximal terrestrial inputs (QFF3362 andQFF3357 Fig 4) while lower ratios were recorded in sam-ples (QFF3354 and QFF3355) with air masses mainly origi-nated from the Arctic Ocean suggesting that the lipid com-pounds in the remote Arctic aerosols had longer atmosphericresidence times Such an observation was in agreement withthose in marine aerosols collected in the western North Pa-cific and Southern Ocean (Bendle et al 2007) In additionconcentrations of linoleic acid were about ten times lowerthan those of oleic acid (Table S1) indicating that C182degrades more quickly than C181 because polyunsaturatedfatty acids are more reactive toward OH NO3 radicals andozone



32

QFF

3352

QFF

3354

QFF

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3356

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3360

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3361

QFF

3362

Con

cent

ratio

n (n

g m

-3) o

r Rat

io

839 840

841

Figure 4 Variations of high molecular weight fatty acids (HMW FA) and low molecular 842

weight fatty acids (LMW FA) in the marine aerosols collected during the MALINA cruise 843

Ratios of C18nC180 are present in circles 844

845

Fig 4 Variations of high molecular weight fatty acids (HMWFA) and low molecular weight fatty acids (LMW FA) in themarine aerosols collected during the MALINA cruise Ratios ofC18nC180 are present in circles

Normal C12ndashC30 fatty alcohols were detected in the ma-rine aerosols with a maximum at C14 or C16 Their distribu-tions are characterized by even carbon number predominance(CPI = 29ndash178 for C20ndashC30) Among the HMW speciesC28 was the dominant species (Table S1) The homologuesltC20 are abundant in soil microbes and marine biota whilethe homologuesgtC24 are abundant in terrestrial higher plantwaxes and loess deposits Although biomass burning processcan emit a large amount of fatty alcohols and fatty acids intothe atmosphere (Simoneit 2002) the contribution of biomassburning to fatty alcohols in the marine atmosphere duringthe MALINA campaign should be minor a point mentionedearlier in Sect 321 Total concentration ranges of HMWn-alcohols (C24ndashC30) are 011ndash31 ng mminus3 (Table 1) withmaximum in QFF3357 and QFF3362 Similar patterns werealso observed for HMW fatty acids and HMWn-alkanes (Ta-ble 1)

323 Primary saccharides

Primary saccharides consisting of glucose fructose sucrosemaltose and trehalose as well as some sugar alcohols includ-ing glycerol erythritol arabitol mannitol and inositol weredetected in the aerosols over the Arctic Ocean (Table S1)Their concentrations ranged from 091 to 112 ng mminus3 (mean245 ng mminus3) They are derived from numerous sources in-cluding microorganisms plants and animals (Simoneit et al2004a) They have been used as tracers for primary biologicalaerosol particles (Graham et al 2003) and resuspension ofsurface soil and unpaved road dust (Simoneit et al 2004a)For example arabitol and mannitol are tracers for airbornefungal spores (Lewis and Smith 1967 Bauer et al 2008)

33

QFF

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FF33

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3357

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3358

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QFF

3361

Q

FF33

62

Rel

ativ

e ab

unda

nce

()

846 847

Figure 5 Relative abundances of isoprene SOA tracers detected in the marine aerosols 848

849

Fig 5Relative abundances of isoprene SOA tracers detected in themarine aerosols

The maximum concentrations of mannitol were observed inQFF3357 and QFF3362 (Table 1) As discussed earlier thesetwo samples were heavily influenced by air masses from in-land In fact mannitol was one of the most abundant com-pounds among all the measured organic species in the marineaerosol samples (Table S1 and Fig 2) indicating an impor-tant contribution of terrestrial fungal spores to the summer-time aerosols over the Arctic Ocean This is reasonable be-cause the majority of fungi have terrestrial habitats in soilsor dead plant matter while ocean is generally a weak sourceof spores (Burshtein et al 2011 Frohlich-Nowoisky et al2012) although fungal spores have been reported in marineaerosols near Antarctica (Frohlich-Nowoisky et al 2012)

A good correlation was found between mannitol and inos-itol (R2 = 087plt001) in the marine aerosols suggestinga similar source Ergosterol which is a primary fungal mem-brane sterol and a specific biomarker for fungi (Lau et al2006) correlated well with mannitol (R2 = 096plt001)Arabitol and mannitol are both considered as specific tracersfor fungi (Bauer et al 2008 Zhang et al 2010) while a rel-atively weak correlation (R2 = 048plt001) was observedbetween them Different fungal species may contain differ-ent levels of arabitol and mannitol (Bauer et al 2008) Sucha weak correlation between arabitol and mannitol may implya high diversity of fungal spores in the marine aerosols thatwere emitted not only from the Arctic Ocean but also fromterrestrial regions through long-range atmospheric transport

The concentrations of trehalose ranged from 001to 87 ng mminus3 which were higher than those (below01 ng mminus3) reported in the high Arctic aerosols collectedin winterndashspring (Fu et al 2009a) Trehalose is present ina variety of microorganisms (fungi bacteria and yeast) and



Table 2 Summary of organic carbon concentrations (microgC mminus3)

from biogenic primary emission (fungal-spore OC) and photochem-ical formation (biogenic SOC) and their contributions in aerosol OC() in the marine aerosol samples

Components range mean std

Concentration (ngC mminus3)

Fungal spore OC 040ndash407 701 124Isoprene SOC 080ndash193 230 598αminusPinene SOC 19ndash104 208 383βminusCaryophyllene SOC 022-21 073 064Sum of SOC 37ndash298 446 943Subtotal 51ndash510 115 186

Percentage in aerosol OC ()

Fungal spore OC 011ndash262 107 89Isoprene SOC 041ndash298 38 91αminusPinene SOC 057ndash161 29 47βminusCaryophyllene SOC 007ndash051 019 013Sum of SOC in OC 11ndash461 69 138Subtotal 14ndash645 176 187

a few higher plants and invertebrates (Medeiros et al 2006)In the present study the highest level of trehalose was foundin QFF3362 which is in accordance with that of C18nC180indicating a fresh biogenic source Sucrose fructose and glu-cose originate from plant materials such as pollen fruits andtheir fragments (Speranza et al 1997 Baker et al 1998Pacini 2000) It should be noted that surface seawater alsocontains a large amount of organics ranging from small or-ganic acids sugars to large molecular weight proteins whichcan be emitted into the MBL through bubble bursting pro-cesses in remote oceans (Leck and Bigg 2005 Facchini etal 2008 Sempere et al 2008 Hawkins and Russell 2010Schmitt-Kopplin et al 2012) However the Beaufort Seawas oligotrophic in summer with low levels of biological ac-tivities during the MALINA cruise which was characterizedwith low levels of Chla (Table 1)

324 Phthalate esters

Phthalate esters (phthalates) are manufactured worldwide asplasticizers and also used in cosmetics lubricants and otherproducts (Thuren and Larsson 1990) Dimethyl (DMP) di-ethyl (DEP) diisobutyl (DiBP) di-n-butyl (DnBP) and di-(2-ethylhexyl) (DEHP) phthalates were detected in the marineaerosols (Table S1) Their total concentrations were 079ndash124 ng mminus3 (26 ng mminus3) which were higher than those re-ported in the North Sea to high Arctic atmosphere (038ndash102 ng mminus3) during summer in 2004 (Xie et al 2007) Thedominant species is DEHP This is reasonable because Xieet al (2007) reported the particle-bound fractions of phtha-lates in the Arctic region during summertime increased withan increase in the molecular weight In addition the predom-

inance of DEHP has also been reported in urban and ruralaerosols in China (Wang et al 2006) The possible source ofphthalates in the Arctic troposphere may be associated witha long-range transport from mid-latitudes and the subsequentdeposition on the snowice sheet The high Arctic can act as acold sink during winter The deposited phthalates onto snowand ice can be released into the atmosphere with an increasein ambient temperature during springndashsummer

325 Isoprene monoterpene and sesquiterpene SOAtracers

Eight compounds were identified as isoprene SOA trac-ers in the aerosol samples including 2-methylglycericacid three C5-alkene triols two 2-methyltetrols (2-methylthreitol and 2-methylerythritol) andcis- andtrans-3-methyltetrahydrofuran-34-diols (3-MeTHF-34-diols) Con-centration ranges of 2-methylthreitol and 2-methylerythritolwere 0034ndash94 ng mminus3 (mean 11 ng mminus3) and 0026ndash190 ng mminus3 (21 ng mminus3) respectively These values are 1ndash3orders of magnitude lower than those reported in urban andforest aerosols in low to mid-latitudes (Wang et al 2005bKleindienst et al 2007 Fu et al 2010) However the con-centrations of 2-methyltetrols in the marine aerosols col-lected over the Arctic Ocean in August 2009 are higher thanthose (mean 0074 ng mminus3) reported in Canadian high Arcticaerosols collected during winterndashspring (Fu et al 2009b)suggesting an enhanced emission of isoprene followed byphotooxidation in summer C5-alkene triols which are re-ported as photooxidation products of isoprene (Wang et al2005b) were detected in all samples with a concentrationrange of 0005ndash19 ng mminus3 (mean 039 ng mminus3) (Table S1)2-Methylglyceric acid (2-MGA) is possibly formed by fur-ther oxidation of methacrolein and methacrylic acid Theconcentration range of 2-methylglyceric acid in the marineaerosols was 0064ndash18 ng mminus3 (041 ng mminus3) Concentra-tions of 3-MeTHF-34-diols were estimated using a surrogateof meso-erythritol due to the lack of authentic standards theirvalues ranged from 0001 to 0070 ng mminus3 (0013 ng mminus3)which were much lower than that (27 ng mminus3) reported inone ambient PM25 sample collected in Yorkville GA dur-ing the summer of 2010 (Lin et al 2012)

The detected monoterpene oxidation products includepinonic acid pinic acid 3-hydroxyglutaric acid (3-HGA)3-(2-hydroxyethyl)-22-dimethylcyclobutanecarboxylicacid (HDCCA) 3-acetylglutaric acid 3-acetyladipicacid 3-isopropylglutaric acid and 3-methyl-123-butanetricarboxylic acid (MBTCA) Total concentrations ofmonoterpene SOA tracers ranged from 044 to 241 ng mminus3

(48 ng mminus3) with the predominance of 3-acetyladipic acid(mean 15 ng mminus3) The formation of MBTCA can beexplained by further reaction ofcis-pinonic acid with OHradical (Szmigielski et al 2007) Thus it has been con-sidered as a higher-generation product However MBTCA(mean 0007 ng mminus3) was found to be a minor species



among the monoterpene SOA tracers Such a phenomenonwas previously reported in aerosols over the remote Pacificand Atlantic oceans where MBTCA was also found tobe less significant than those in the coastal aerosols (Fuet al 2011) suggesting a relatively short atmosphericlifetime of MBTCA β-Caryophyllinic acid formed eitherby ozonolysis or photo-oxidation ofβ-caryophyllene (Jaouiet al 2007) was identified in all the samples ranging from0005 to 0048 ng mminus3 (0017 ng mminus3)

In Figure 5 the relative abundance of isoprene SOA trac-ers shows that 2-methyltetrols are found as the major speciesin the marine aerosol samples followed by 2-methylglycericacid and C5-alkene triols being similar to those in ma-rine aerosols collected during a round-the-world cruise (Fuet al 2011) Figure 6andashd show the variation of isopreneSOA tracers among the marine aerosol samples with obviousdifferent patterns which may imply their different forma-tion processes andor atmospheric fates For example cham-ber experiments have demonstrated that 2-methylglycericacid is formed under high-NOx conditions while the 2-methyltetrols are mainly generated under low-NOx condi-tions (Surratt et al 2006) Paulot et al (2009) reported thatgas-phase isoprene epoxydiols (IEPOX) that formed from theoxidation of isoprene hydroxyhydroperoxides (ISOPOOH)are likely to be key intermediates for isoprene SOA underlow-NOx conditions Recent studies (Surratt et al 2010 Linet al 2012) have shown that IEPOX reactively uptakes ontosulfate aerosols to yield 3-MeTHF-34-diols 2-methyltetrolsC5-alkene triols dimers and IEPOX-derived organosulfatesRecently 3-MeTHF-34-diols are proposed to be formedthrough the acid-catalyzed intramolecular rearrangement ofisoprene epoxydiols under low-NOx conditions (Lin et al2012)

In a previous study the concentration ratios of C5-alkenetriols to 2-methyltetrols were found to belt010 in marineaerosols over the open oceans (Fu et al 2011) while theywere much higher (up to 066) over the coastal regions suchas off the California coast in the Indian Ocean near Indiaand the South China Sea The lower ratios in the pristine openoceans are in agreement with the low ratios (lt010) obtainedin laboratory experiments for the isoprene photooxidation inthe absence of NOx (Kleindienst et al 2009) The low ratiosobtained in remote marine aerosols and the presence of C=Cbond in the structure of C5-alkene triols may suggest a signif-icant chemical decomposition during long-range transportIn the present study a large variation of the concentrationratios of C5-alkene triols to 2-methyltetrols (002ndash13) wasobserved with the largest value of QFF3357 (Fig 7) Sur-ratt et al (2010) reported that relative humidity can affect theconcentration ratio of C5-alkene triols to 2-methyltetrols inthe absence of NOx Although both QFF3357 and QFF3362were collected during humid and foggy days with high levelsof isoprene SOA tracer a very low ratio was obtained for thelatter sample (Fig 7) Such a pattern is consistent with those

34

0

2500

5000

0

005

01

0

15

3

0

20

40

0

15

3

0

004

008

(a) 2-Methyltetrols

(b) C5-alkene triols

(c) 3-MeTHF-34-diols

(d) 2-MGA

(e) Sulfate

Con

cent

ratio

n (n

g m

-3)

[H+ ]

(microm

ol m

-3)

(f) Aerosol acidity

QFF

3352

Q

FF33

54

QFF

3355

Q

FF33

56

QFF

3357

Q

FF33

58

QFF

3359

Q

FF33

60

QFF

3361

Q

FF33

62

850

851

Figure 6 Concentrations of isoprene SOA tracers and aerosol acidity measured in the marine 852

aerosols collected over the Arctic Ocean during the MALINA campaign in August 2009 853

854

Fig 6 Concentrations of isoprene SOA tracers and aerosol aciditymeasured in the marine aerosols collected over the Arctic Oceanduring the MALINA campaign in August 2009

of sulfate loading (Fig 6e) indicating an influence of aerosolacidity

Aerosol acidity has been reported to have significant im-pacts on SOA formation from the oxidation of isoprene andother biogenic VOCs (eg Surratt et al 2007 Offenberg etal 2009) In the present study the aerosol acidity (Ziembaet al 2007) was roughly estimated by [H+] = 2[SO2minus

4 ] +

[NOminus

3 ] ndash [NH+

4 ] where the brackets represent ion concen-trations in molar units that were measured using ion chro-matography (761 Compact IC Metrohm Switzerland) Asshown in Figure 6f the [H+] values ranged from 0002 to0060 micromol mminus3 QFF3357 showed much stronger aciditythan the other samples which indicates that the aerosol acid-ity may enhance the formation of C5-alkene triols rather than2-methyltetrols in the pristine atmosphere over the ArcticOcean Furthermore aerosol acidity can favor the formation



35

QFF

3352

QFF

3354

QFF

3355

QFF

3356

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n R

atio

855

856

Figure 7 Concentration ratios of isoprene SOA tracers measured in the summertime marine 857

aerosols collected during the MALINA cruise in the Arctic Ocean 858

859

Fig 7Concentration ratios of isoprene SOA tracers measured in thesummertime marine aerosols collected during the MALINA cruisein the Arctic Ocean

of 3-MeTHF-34-diols and 2-MGA (Fig 6cndashd) Interestinglya strong positive correlation (R2 = 095) was observed be-tween 3-MeTHF-34-diols and C5-alkene triols (Fig 8) inmarine aerosols over the Arctic Ocean which supports theidea that both of them can be formed through the oxidationof IEPOX under low-NOx conditions (Surratt et al 2010Lin et al 2012)

Two diastereoisomeric 2-methyltetrols (2-methylthreitoland 2-methylerythritol) were first identified as oxidationproducts of isoprene in the Amazonian forest aerosols(Claeys et al 2004) Since then these organic marker com-pounds have been detected in ambient aerosols from differentlocations in the world (Hallquist et al 2009 and referencestherein) Concentrations of 2-methylerythritol are generally15ndash25 times more abundant than that of 2-methylthreitolin ambient aerosols (Claeys et al 2004 Cahill et al 2006Fu et al 2010) Interestingly rather lower ratios of 2-methylerythritol to 2-methylthreitol (down to 076) were ob-served in the summertime marine aerosols over the ArcticOcean ranging from 076ndash21 (Fig 7) Such a variation in-dicates that the formation processes andor the sources of thetwo isomers varied with time and location this also indicatesthat one of the isomers may have a larger preference to at-mospheric oxidative aging (ie heterogeneous reaction withhydroxyl radicals) during long-range transport Another pos-sibility is that such a difference may be due to one isomericepoxide preferentially produced in the gas phase oxidationof isoprene (Paulot et al 2009) In addition Noziere etal (2011) recently reported that 2-methyltetrols could be ofbiogenic origin at a certain level A good correlation between2-methyltetrols and sugar compounds was also reported by

36

y = 2992x + 0007 Rsup2 = 095 plt005 n=10

0

05

1

15

2

25

0 002 004 006 008

3-MeTHF-34-diols (ng m-3)

C5-

alke

ne tr

iols

(ng

m-3

)

860

861

Figure 8 Linear correlation between the concentrations of 3-MeTHF-34-diols and C5-alkene 862

triols measured in the summertime marine aerosols collected during the MALINA cruise 863

864

Fig 8Linear correlation between the concentrations of 3-MeTHF-34-diols and C5-alkene triols measured in the summertime marineaerosols collected during the MALINA cruise

Cahill et al (2006) who proposed that 2-methyltetrols mayarise directly from a similar biological source as sugars in ad-dition to the well-documented photochemical pathway Fur-ther from Fig 7 we can obtain an intriguing negative cor-relation (R2 = 041plt001 n = 10) between the concen-tration ratios of 2-methylerythritol to 2-methylthreitol andC5-alkene triols to 2-methyltetrols which warrants a furtherstudy

326 Other polar organic acids

Seven aromatic acids were detected in the marine aerosolsincluding three phthalic acids and four hydroxybenzoic acids(Table S1) Their total concentrations ranged from 0056to 18 ng mminus3 (037 ng mminus3) Phthalic acids have been pro-posed as a surrogate for the contributions of secondary oxi-dation to organic aerosols although primary sources such asbiomass burning and fossil fuel combustion cannot be ex-cluded (Kawamura and Yasui 2005 Kundu et al 2010)Their isomeric composition was characterized by a predomi-nance of phthalic acid (Table S1) being consistent with thosereported in continental aerosols (Wang et al 2006)

Other hydroxypolyacids including glycolic (hydroxy-acetic acid) lactic glyceric malic and tricarballylic acidswere detected in the Arctic Ocean aerosols with the pre-dominance of malic acid (Table S1) Glycolic acid isthe smallestα-hydroxy acid It is hygroscopic and highlywater-soluble The concentration range of glycolic acid was012ndash15 ng mminus3 (065 ng mminus3) which was lower than those(034ndash43 ng mminus3 20 ng mminus3) in wintertime Arctic aerosols(Fu et al 2009b) Polyacids such as malic acid are also con-sidered as secondary oxidation products of precursor organic



compounds In addition biomass burning can emit malic acidand other dicarboxylic acids andor their precursors into theatmosphere (Kundu et al 2010)

33 Source strength of organic aerosols

Based on previously studied emission profiles of organiccompounds (Schauer et al 1996 Simoneit et al 2004b) andthe above discussion organic compound classes quantifiedin the marine aerosols from the Arctic Ocean can be roughlyapportioned to five emission sources and one photooxidationproduct group as follows (a) ldquoterrestrial natural backgroundrdquocharacterized by higher plant waxn-alkanes HMW fattyacids and fatty alcohols (b) ldquomarine natural backgroundrdquomainly reflected from LMW fatty acids LMW fatty alco-hols and cholesterol (c) ldquobiomass burningrdquo characterized bylevoglucosan and its isomersβ-sitosterol 4-hydroxybenzoicacid and ligninresin acids (d) ldquoprimary biological originrdquocharacterized by primary saccharides and reduced sugars aswell as ergosterol and (e) ldquophotooxidationrdquo reflected by bio-genic SOA tracers aromatic acids and hydroxy-polyacidsLMW dicarboxylic acids that are also of photochemical ori-gin and abundant in atmospheric aerosols were not includedin this study According to the above-mentioned categoriesall the measured organic species were converted into theircarbon contents to calculate the relative abundances of eachcategory As shown in Fig 9 the most abundant groupwas primary biological origin (99ndash66 mean 46 ) fol-lowed by photooxidation (96ndash402 216 ) marine natu-ral background (83ndash340 163 ) plastic emission (19ndash127 83 ) biomass burning (11ndash128 43 ) andterrestrial natural background (22ndash63 36 ) Interest-ingly QFF3354 obtained the highest contribution to marinenatural emissions this sample was collected during the pe-riod when the biological activity was higher than other sam-pling periods as seen from Chla (Table 1)

In order to obtain further information on the relative abun-dances of organic aerosols from primary and secondarysources some tracer-based methods were used to estimatetheir contributions to aerosol OC Here the measured con-centrations of mannitol were used to calculate the con-tributions of fungal spores to OC (Bauer et al 2008)The measured biogenic SOA tracers were used to esti-mate the secondary organic carbon (SOC) formed fromthe oxidation of isopreneα-pinene andβ-caryophylleneusing a tracer-based method (Kleindienst et al 2007) Itshould be noted that such estimation might suffer from alarge uncertainty a point that has been discussed in de-tails by Yttri et al (2011a b) and El Haddad et al (2011)As shown in Table 2 fungal-sporendashderived OC rang-ing from 040 to 407 ngC mminus3 was by far the domi-nant source which accounts for 011ndash262 (107) ofaerosol OC For biogenic SOC the isoprene-derived SOC(080ndash193 ngC mminus3 mean 230 ngC mminus3) was comparablewith those of α-pinenendashderived SOC (19ndash104 ngC mminus3

37

QFF

3352

QFF

3354

QFF

3355

Q

FF33

56

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Rel

ativ

e ab

unda

nce

()

865

866

Figure 9 Source strengths of organic species measured in the marine aerosols collected 867

during the MALINA campaign 868

Fig 9 Source strengths of organic species measured in the marineaerosols collected during the MALINA campaign

208 ngC mminus3) β-Caryophyllenendashderived SOC was ratherminor (022ndash21 ngC mminus3 073 ngC mminus3) only accountingfor 007ndash051 (019 ) of OC In total these biogenic pri-mary emission source and secondary aerosol formation cancontribute 14ndash645 of OC with an average of 176 Such a low percentage suggests that the major portion ofmarine organic aerosols in the Arctic Ocean is still notspecified at a molecular level The unknown portion mayinclude oligomers organosulfates organic nitrates aminoacids humic-like substances HMW organics such as pro-teins as well as other bioaerosols that are either from theocean surface water through bubble bursting or from long-range atmospheric transport

4 Conclusions

Ten organic compound classes were measured in ma-rine aerosols collected in the southern Beaufort SeaCanadian Arctic The identified organics (73ndash185 ng mminus3476 ng mminus3) were more abundant in the samples that wereinfluenced by air masses from northern Canada Distribu-tions of biogenic SOA tracers in the marine aerosols werecharacterized by a predominance of isoprene andα-pineneoxidation products whileβ-caryophyllene oxidation was aminor contributor Total measured organic species accountedfor 18ndash11 (41 ) of OC among which sugar compounds



were the main contributor By using a tracer-based methodbiogenic SOC can account for 11ndash461 (69 ) of aerosolOC This is still lower than the contribution of fungal-sporendashderived OC which on average accounted for 107 of aerosol OC highlighting the importance of primary bio-logical aerosols in the MBL over the Arctic Ocean in sum-mer Similarly the results of source apportionment show thatthe identified organics in the MBL over the Arctic Oceanare mainly of primary biological origin followed by sec-ondary aerosol formation In addition the large variation oforganic chemical composition of both primary and secondaryorganic aerosol tracers in different samples implies a verycomplex nature of marine aerosols over the Arctic OceanFurther study is needed to characterize the seasonal variationand size distribution of organic aerosols and to better evalu-ate the impact of primary bioaerosols and biogenic VOCs onthe aerosol chemistry in the polar regions

Supplementary material related to this article isavailable online athttpwwwbiogeosciencesnet106532013bg-10-653-2013-supplementpdf

AcknowledgementsThis study is in part supported by the JapaneseMinistry of Education Science Sport and Culture (grant-in-aidNo 19204055) and by the Environment Research and TechnologyDevelopment Fund of the Ministry of the Environment Japan(B-0903) P F appreciates the financial support from the JapanSociety for the Promotion of Science (JSPS) and the ChineseNational Natural Science Foundation (No 41175106) We thankSimon Belanger for providing the Chla data This study wasconducted as a part of the Malina Scientific Program funded byANR (Agence nationale de la recherche) INSU-CNRS (Institutnational des sciences de lrsquounivers ndash Centre national de la recherchescientifique) CNES (Centre national drsquoetudes spatiales) and ESA(European Space Agency) We are grateful to M Babin PI of theMalina Project as well as the captain and crews of the CanadianIcebreakerCCGS Amundsen Special thanks to Julien Para for hishelp during the aerosol sampling

Edited by S Belanger

References

Anttila T Langmann B Varghese S and OrsquoDowd C Con-tribution of isoprene oxidation products to marine aerosolover the North-East Atlantic Adv Meteorol 2010 482603doi1011552010482603 2010

Arnold S R Spracklen D V Williams J Yassaa N SciareJ Bonsang B Gros V Peeken I Lewis A C Alvain Sand Moulin C Evaluation of the global oceanic isoprene sourceand its impacts on marine organic carbon aerosol Atmos ChemPhys 9 1253ndash1262doi105194acp-9-1253-2009 2009

Baker H G Baker I and Hodges S A Sugar composition ofnectars and fruits consumed by birds and bats in the tropics andsubtropics Biotropica 30 559ndash586 1998

Barrie L A Arctic air pollution an overview of current knowl-edge Atmos Environ 20 643ndash663 1986

Bauer H Claeys M Vermeylen R Schueller E Weinke GBerger A and Puxbaum H Arabitol and mannitol as tracersfor the quantification of airborne fungal spores Atmos Environ42 588ndash593 2008

Bendle J Kawamura K Yamazaki K and Niwai T Latitu-dinal distribution of terrestrial lipid biomarkers andn-alkanecompound-specific stable carbon isotope ratios in the atmosphereover the western Pacific and Southern Ocean Geochim Cos-mochim Ac 71 5934ndash5955 2007

Burshtein N Lang-Yona N and Rudich Y Ergosterol ara-bitol and mannitol as tracers for biogenic aerosols in theeastern Mediterranean Atmos Chem Phys 11 829ndash839doi105194acp-11-829-2011 2011

Cahill T M Seaman V Y Charles M J Holzinger R andGoldstein A H Secondary organic aerosols formed from ox-idation of biogenic volatile organic compounds in the SierraNevada Mountains of California J Geophys Res 111 D16312doi1010292006JD007178 2006

Claeys M Graham B Vas G Wang W Vermeylen R Pashyn-ska V Cafmeyer J Guyon P Andreae M O Artaxo P andMaenhaut W Formation of secondary organic aerosols throughphotooxidation of isoprene Science 303 1173ndash1176 2004

Claeys M Wang W Vermeylen R Kourtchev I Chi X FarhatY Surratt J D Gomez-Gonzalez Y Sciare J and MaenhautW Chemical characterization of marine aerosol at AmsterdamIsland during the austral summer of 2006ndash2007 J Aerosol Sci41 13ndash22 2010

Eglinton G and Hamilton R J Leaf epicuticular waxes Science156 1322ndash1335 1967

El Haddad I Marchand N Temime-Roussel B Wortham HPiot C Besombes J-L Baduel C Voisin D ArmengaudA and Jaffrezo J-L Insights into the secondary fraction ofthe organic aerosol in a Mediterranean urban area MarseilleAtmos Chem Phys 11 2059ndash2079doi105194acp-11-2059-2011 2011

Ekstrom S Noziere B and Hansson H-C The Cloud Con-densation Nuclei (CCN) properties of 2-methyltetrols and C3-C6 polyols from osmolality and surface tension measurementsAtmos Chem Phys 9 973ndash980doi105194acp-9-973-20092009

Facchini M C Rinaldi M Decesari S Carbone C Finessi EMircea M Fuzzi S Ceburnis D Flagan R Nilsson E Dde Leeuw G Martino M Woeltjen J and OrsquoDowd C DPrimary submicron marine aerosol dominated by insoluble or-ganic colloids and aggregates Geophys Res Lett 35 L17814doi1010292008GL034210 2008

Fine P M Cass G R and Simoneit B R T Chemical char-acterization of fine particle emissions from fireplace combustionof woods grown in the northeastern United States Environ SciTechnol 35 2665ndash2675 2001

Frohlich-Nowoisky J Burrows S M Xie Z Engling GSolomon P A Fraser M P Mayol-Bracero O L ArtaxoP Begerow D Conrad R Andreae M O Despres V Rand Poschl U Biogeography in the air fungal diversity over



land and oceans Biogeosciences 9 1125ndash1136doi105194bg-9-1125-2012 2012

Fu P Q Kawamura K and Barrie L A Photochemical andother sources of organic compounds in the Canadian high Arcticaerosol pollution during winter-spring Environ Sci Technol43 286ndash292 2009a

Fu P Q Kawamura K Chen J and Barrie L A Isoprenemonoterpene and sesquiterpene oxidation products in the highArctic aerosols during late winter to early summer Environ SciTechnol 43 4022ndash4028 2009b

Fu P Q Kawamura K Kanaya Y and Wang Z F Contribu-tions of biogenic volatile organic compounds to the formationof secondary organic aerosols over Mt Tai Central East ChinaAtmos Environ 44 4817ndash4826 2010

Fu P Q Kawamura K and Miura K Molecular char-acterization of marine organic aerosols collected duringa round-the-world cruise J Geophys Res 116 D13302doi1010292011JD015604 2011

Gantt B Meskhidze N and Kamykowski D A new physically-based quantification of marine isoprene and primary or-ganic aerosol emissions Atmos Chem Phys 9 4915ndash4927doi105194acp-9-4915-2009 2009

Graham B Guyon P Taylor P E Artaxo P Maenhaut WGlovsky M M Flagan R C and Andreae M O Organiccompounds present in the natural Amazonian aerosol Character-ization by gas chromatography-mass spectrometry J GeophysRes 108 4766doi1010292003JD003990 2003

Hallquist M Wenger J C Baltensperger U Rudich Y Simp-son D Claeys M Dommen J Donahue N M GeorgeC Goldstein A H Hamilton J F Herrmann H Hoff-mann T Iinuma Y Jang M Jenkin M E Jimenez J LKiendler-Scharr A Maenhaut W McFiggans G Mentel ThF Monod A Prevot A S H Seinfeld J H Surratt J DSzmigielski R and Wildt J The formation properties and im-pact of secondary organic aerosol current and emerging issuesAtmos Chem Phys 9 5155ndash5236doi105194acp-9-5155-2009 2009

Hawkins L N and Russell L M Polysaccharides pro-teins and phytoplankton fragments Four chemically distincttypes of marine primary organic aerosol classified by sin-gle particle spectromicroscopy Adv Meteorol 2010 612132doi1011552010612132 2010

Hoffmann D Tilgner A Iinuma Y and Herrmann H Atmo-spheric stability of levoglucosan a detailed laboratory and mod-eling study Environ Sci Technol 44 694ndash699 2010

Iziomon M G Lohmann U and Quinn P K Summertime pol-lution events in the Arctic and potential implications J GeophysRes 111 D12206doi1010292005JD006223 2006

Jaoui M Lewandowski M Kleindienst T E Offenberg J Hand Edney E Oβ-Caryophyllinic acid An atmospheric tracerfor β-caryophyllene secondary organic aerosol Geophys ResLett 34 L05816doi1010292006GL028827 2007

Kawamura K and Gagosian R B Implications ofω-oxocarboxylic acids in the remote marine atmosphere for photo-oxidation of unsaturated fatty acids Nature 325 330ndash332 1987

Kawamura K Ishimura Y and Yamazaki K Four yearsrsquo obser-vations of terrestrial lipid class compounds in marine aerosolsfrom the western North Pacific Global Biogeochem Cycles 171003doi1010292001GB001810 2003

Kawamura K and Yasui O Diurnal changes in the distributionof dicarboxylic acids ketocarboxylic acids and dicarbonyls inthe urban Tokyo atmosphere Atmos Environ 39 1945ndash19602005

Kawamura K Ono K Tachibana E Charriere B and SempereR Distributions of low molecular weight dicarboxylic acids ke-toacids andα-dicarbonyls in the marine aerosols collected overthe Arctic Ocean during late summer Biogeosciences 9 4725ndash4737doi105194bg-9-4725-2012 2012

Kleindienst T E Jaoui M Lewandowski M Offenberg J HLewis C W Bhave P V and Edney E O Estimates of the con-tributions of biogenic and anthropogenic hydrocarbons to sec-ondary organic aerosol at a southeastern US location AtmosEnviron 41 8288ndash8300 2007

Kleindienst T E Lewandowski M Offenberg J H Jaoui Mand Edney E O The formation of secondary organic aerosolfrom the isoprene + OH reaction in the absence of NOx At-mos Chem Phys 9 6541ndash6558doi105194acp-9-6541-20092009

Kundu S Kawamura K Andreae T W Hoffer A and An-dreae M O Molecular distributions of dicarboxylic acidsketocarboxylic acids andα-dicarbonyls in biomass burningaerosols implications for photochemical production and degra-dation in smoke layers Atmos Chem Phys 10 2209ndash2225doi105194acp-10-2209-2010 2010

Langmann L Scannell C and OrsquoDowd C D New directionsorganic matter contribution to marine aerosols and cloud con-densation nuclei Atmos Environ 42 7821ndash7822 2008

Lau A P S Lee A K Y Chan C K and Fang M Ergosterolas a biomarker for the quantification of the fungal biomass inatmospheric aerosols Atmos Environ 40 249ndash259 2006

Law K S and Stohl A Arctic air pollution Origins and impactsScience 315 1537ndash1540 2007

Leck C and Bigg K Biogenic particles in the surface microlayerand overlaying atmosphere in the central Arctic Ocean duringsummer Tellus 57B 305ndash316 2005

Lewis D H and Smith D C Sugar alcohols (polyols) in fungiand green plants 1 Distributions physiology and metabolismNew Phytol 66 143ndash184 1967

Lin Y-H Zhang Z Docherty K S Zhang H BudisulistioriniS H Rubitschun C L Shaw S L Knipping E M EdgertonE S Kleindienst T E Gold A and Surratt J D Isopreneepoxydiols as precursors to secondary organic aerosol forma-tion acid-catalyzed reactive uptake studies with authentic com-pounds Environ Sci Technol 46 250ndash258 2012

Medeiros P M Conte M H Weber J C and Simoneit BR T Sugars as source indicators of biogenic organic carbonin aerosols collected above the Howland Experimental ForestMaine Atmos Environ 40 1694ndash1705 2006

Meskhidze N and Nenes A Phytoplankton and cloudiness in theSouthern Ocean Science 314 1419ndash1423 2006

Myriokefalitakis S Vignati E Tsigaridis K Papadimas CSciare J Mihalopoulos N Facchini M C Rinaldi M Den-tener F J Ceburnis D Hatzianastasiou N OrsquoDowd CD van Weele M and Kanakidou M Global modeling ofthe oceanic source of organic aerosols Adv Meteorol 2010939171doi1011552010939171 2010

Neususzlig C Plewka A Herrmann H and Quinn P K Carbona-ceous aerosol over the Indian Ocean OCEC fractions and se-



lected specifications from size-segregated onboard samples JGeophys Res 107 8031doi1010292001JD000327 2002

Noziere B Gonzalez N J D Borg-Karlson A-K Pei Y Re-deby J P Krejci R Dommen J Prevot A S H and An-thonsen T Atmospheric chemistry in stereo A new look at sec-ondary organic aerosols from isoprene Geophys Res Lett 38L11807doi1010292011GL047323 2011

OrsquoDowd C D Facchini M C Cavalli F Ceburnis D MirceaM Decesari S Fuzzi S Yoon Y J and Putaud J P Bio-genically driven organic contribution to marine aerosol Nature431 676ndash680 2004

OrsquoDowd C D and de Leeuw G Marine aerosol production areview of the current knowledge Phil Trans R Soc A 3651753ndash1774 2007

Offenberg J H Lewandowski M Edney E O Kleindienst TE and Jaoui M Influence of aerosol acidity on the formationof secondary organic aerosol from biogenic precursor hydrocar-bons Environ Sci Technol 43 7742ndash7747 2009

Pacini E From anther and pollen ripening to pollen presentationPlant Sys Evol 222 19ndash43 2000

Paris J-D Stohl A Nedelec P Arshinov M Yu PanchenkoM V Shmargunov V P Law K S Belan B D and Ciais PWildfire smoke in the Siberian Arctic in summer source charac-terization and plume evolution from airborne measurements At-mos Chem Phys 9 9315ndash9327doi105194acp-9-9315-20092009

Paulot F Crounse J D Kjaergaard H G Kurten A St ClairJ M Seinfeld J H and Wennberg P O Unexpected epoxideformation in the gas-phase photooxidation of isoprene Science325 730ndash733 2009

Quinn P K Shaw G Andrews E Dutton E G Ruoho-AirolaT and Gong S L Arctic haze current trends and knowledgegaps Tellus 59B 99ndash114 2007

Rinaldi M Decesari S Finessi E Giulianelli L Carbone CFuzzi S OrsquoDowd C D Ceburnis D and Facchini M C Pri-mary and secondary organic marine aerosol and oceanic biologi-cal activity recent results and new perspectives for future studiesAdv Meteorol 2010 310682doi1011552010310682 2010

Rogge W F Mazurek M A Hildemann L M Cass G R andSimoneit B R T Quantification of urban organic aerosols ata molecular level Identification abundance and seasonal varia-tion Atmos Environ Part A 27 1309ndash1330 1993

Rontani J-F Charriere B Forest A Heussner S Vaultier FPetit M Delsaut N Fortier L and Sempere R Intense pho-tooxidative degradation of planktonic and bacterial lipids in sink-ing particles collected with sediment traps across the CanadianBeaufort Shelf (Arctic Ocean) Biogeosciences 9 4787ndash4802doi105194bg-9-4787-2012 2012

Schauer J J Rogge W F Hildemann L M Mazurek M A andCass G R Source apportionment of airborne particulate matterusing organic compounds as tracers Atmos Environ 30 3837ndash3855 1996

Schmitt-Kopplin P Liger-Belair G Koch B P Flerus RKattner G Harir M Kanawati B Lucio M Tziotis DHertkorn N and Gebefugi I Dissolved organic matter in seaspray a transfer study from marine surface water to aerosolsBiogeosciences 9 1571ndash1582doi105194bg-9-1571-20122012

Sempere R Tedetti M Panagiotopoulos C Charriere B andVan Wambeke F Distribution and bacterial availability of dis-solved neutral sugars in the South East Pacific Biogeosciences5 1165ndash1173doi105194bg-5-1165-2008 2008

Simoneit B R T Organic matter in eolian dusts over the AtlanticOcean Mar Chem 5 443ndash464 1977

Simoneit B R T and Mazurek M A Organic matter of thetroposphere-II Natural background of biogenic lipid matter inaerosols over the rural western United States Atmos Environ16 2139ndash2159 1982

Simoneit B R T Cardoso J N and Robinson N An assessmentof terrestrial higher molecular weight lipid compounds in aerosolparticulate matter over the south Atlantic from about 30ndash70 SChemosphere 23 447ndash465 1991

Simoneit B R T Biomass burning-a review of organic tracers forsmoke from incomplete combustion Appl Geochem 17 129ndash162 2002

Simoneit B R T Elias V O Kobayashi M Kawamura KRushdi A I Medeiros P M Rogge W F and Didyk B MSugars-dominant water-soluble organic compounds in soils andcharacterization as tracers in atmospheric particulate matter En-viron Sci Technol 38 5939ndash5949 2004a

Simoneit B R T Kobayashi M Mochida M Kawamura KLee M Lim H J Turpin B J and Komazaki Y Composi-tion and major sources of organic compounds of aerosol particu-late matter sampled during the ACE-Asia campaign J GeophysRes 109 D19S10doi1010292004JD004598 2004b

Speranza A Calzoni G L and Pacini E Occurrence of mono-or disaccharides and polysaccharide reserves in mature pollengrains Sex Plant Reprod 10 110ndash115 1997

Spracklen D V Arnold S R Sciare J Carslaw K and Pio CGlobally significant oceanic source of organic carbon aerosolGeophys Res Lett 35 L12811doi1010292008GL0333592008

Stohl A Berg T Burkhart J F Fjaeacuteaeligraa A M Forster CHerber A Hov Oslash Lunder C McMillan W W OltmansS Shiobara M Simpson D Solberg S Stebel K StromJ Toslashrseth K Treffeisen R Virkkunen K and Yttri K EArctic smoke ndash record high air pollution levels in the EuropeanArctic due to agricultural fires in Eastern Europe in spring 2006Atmos Chem Phys 7 511ndash534doi105194acp-7-511-20072007

Surratt J D Murphy S M Kroll J H Ng N L HildebrandtL Sorooshian A Szmigielski R Vermeylen R MaenhautW Claeys M Flagan R C and Seinfeld J H Chemical com-position of secondary organic aerosol formed from the photoox-idation of isoprene J Phys Chem A 110 9665ndash9690 2006

Surratt J D Lewandowski M Offenberg J H Jaoui M Klein-dienst T E Edney E O and Seinfeld J H Effect of acidityon secondary organic aerosol formation from isoprene EnvironSci Technol 41 5363ndash5369 2007

Surratt J D Chan A W H Eddingsaas N C Chan M NLoza C L Kwan A J Hersey S P Flagan R C WennbergP O and Seinfeld J H Reactive intermediates revealed insecondary organic aerosol formation from isoprene Proc NatlAcad Sci USA 107 6640ndash6645 2010

Szmigielski R Surratt J D Gomez-Gonzalez G Van der VekenP Kourtchev I Vermeylen R Blockhuys F Jaoui M Klein-dienst T E Lewandowski M Offenberg J H Edney E



O Seinfeld J H Maenhaut W and Claeys M 3-Methyl-123-butanetricarboxylic acid An atmospheric tracer for terpenesecondary organic aerosol Geophys Res Lett 34 L24811doi1010292007GL031338 2007

Thuren A and Larsson P Phthalate esters in the Swedish atmo-sphere Environ Sci Technol 24 554ndash559 1990

Wang G H Kawamura K Lee S Ho K F and Cao J JMolecular seasonal and spatial distributions of organic aerosolsfrom fourteen Chinese cities Environ Sci Technol 40 4619-4625 2006

Wang H B Kawamura K and Shooter D Carbonaceous andionic components in wintertime atmospheric aerosols from twoNew Zealand cities Implications for solid fuel combustion At-mos Environ 39 5865ndash5875 2005a

Wang W Kourtchev I Graham B Cafmeyer J Maenhaut Wand Claeys M Characterization of oxygenated derivatives ofisoprene related to 2-methyltetrols in Amazonian aerosols us-ing trimethylsilylation and gas chromatographyion trap massspectrometry Rapid Commu Mass Spectrom 19 1343ndash13512005b

Xie Z Ebinghaus R Temme C Lohmann R Caba A andRuck W Occurrence and air-sea exchange of phthalates in theArctic Environ Sci Technol 41 4555ndash4560 2007

Yassaa N Peeken I Zollner E Bluhm K Arnold S SprchlenD and Williams J Evidence for marine production of monoter-penes Environ Chem 5 391ndash401 2008

Yttri K E Simpson D Noslashjgaard J K Kristensen K GenbergJ Stenstrom K Swietlicki E Hillamo R Aurela M BauerH Offenberg J H Jaoui M Dye C Eckhardt S BurkhartJ F Stohl A and Glasius M Source apportionment of thesummer time carbonaceous aerosol at Nordic rural backgroundsites Atmos Chem Phys 11 13339ndash3357doi105194acp-11-13339-2011 2011a

Yttri K E Simpson D Stenstrom K Puxbaum H andSvendby T Source apportionment of the carbonaceous aerosolin Norway ndash quantitative estimates based on14C thermal-opticaland organic tracer analysis Atmos Chem Phys 11 9375ndash9394doi105194acp-11-9375-2011 2011b

Zhang T Engling G Chan C-Y Zhang Y-N Zhang Z-SLin M Sang X-F Li Y D and Li Y-S Contribution of fun-gal spores to particulate matter in a tropical rainforest EnvironRes Lett 5doi1010881748-932652024010 2010

Ziemba L D Fischer E Griffin R J and Talbot RW Aerosol acidity in rural New England Temporal trendsand source region analysis J Geophys Res 112 D10SS22doi1010292006JD007605 2007



comprise primary organic aerosol (POA) and secondary or-ganic aerosol (SOA) Primary marine organic aerosols canbe produced from the interaction of wind with the ocean sur-face and results in the mechanical production of sea sprayaerosols (Rinaldi et al 2010) The best-known precursor ofmarine POA is dimethyl sulphide (DMS) that is producedbiogenically in the ocean Sea spray aerosols are assumed toenrich in organic matter when the marine surface is charac-terized by high biological activities (OrsquoDowd et al 2004)A recent study (Schmitt-Kopplin et al 2012) provides ev-idence that marine surface water via bubble bursting pro-cesses can produce a significant fraction of primary organicaerosols that typically contain homologous series of oxo-hydroxy- methoxy- branched fatty acids and mono- di- andtricarboxylic acids as well as monoterpenes and sugars

The atmospheric oxidation of volatile organic compounds(VOCs) emitted from the ocean can form SOA (OrsquoDowdand de Leeuw 2007) Traditionally the most studied SOAcomponent in the marine boundary layer (MBL) is methane-sulfonic acid (MSA) which is formed from the oxidationof DMS Other components such as organosulfates (sulfateesters of C9ndashC13 hydroxyl carboxylic acids) can be consid-ered as marine SOA tracers for the oxidation of unsaturatedfatty acids derived from marine algae (Claeys et al 2010)Meskhidze and Nenes (2006) proposed that SOA formationfrom the oxidation of phytoplankton-derived isoprene can af-fect the chemical composition of marine CCN and influencecloud droplet number Laboratory experiments (Ekstrom etal 2009) have shown that 2-methyltetrols tracers for iso-prene SOA (Claeys et al 2004) and related isoprene oxida-tion products can increase CCN levels in the pristine marineatmosphere that is limited in CCN In addition to the oceanicemission of isoprene recent shipboard measurements overthe South Atlantic Ocean have provided the evidence for ma-rine production of monoterpenes (Yassaa et al 2008) How-ever recent modeling studies suggested that the oceanic iso-prene and monoterpene sources are not significant enoughto control marine organic aerosols (Spracklen et al 2008Arnold et al 2009 Gantt et al 2009 Anttila et al 2010)For example Myriokefalitakis et al (2010) proposed thatthe annual global marine SOA from isoprene and monoter-pene oxidation was minor (01 Tg yrminus1) compared to thosefrom the oxidation of DMS (4 Tg yrminus1) and marine amines(1 Tg yrminus1)

Despite considerable advances in primary and secondarymarine aerosol studies during the last decade the chemi-cal nature of marine organic aerosols remains poorly under-stood due to their diverse sources and formation mechanisms(OrsquoDowd and de Leeuw 2007) Marine organic aerosolsare influenced not only by oceanic emissions of primaryaerosols and SOA precursors but also by continental emis-sions through long-range atmospheric transport So far fieldmeasurements concerning organic molecular compositionsof marine aerosols are limited (eg Simoneit et al 1991Simoneit et al 2004b Fu et al 2011) In particular lit-

tle is known about the abundances of biogenic SOA trac-ers from the oxidation of isoprene (eg 2-methyltetrols) andαβ-pinene (eg pinonic and pinic acids) in the MBL (Fu etal 2011) especially in the polar regions During the polarsunrise season the Arctic atmosphere can serve as a uniquephotochemical reactor influenced by marine-derived parti-cles from the Arctic Ocean and continent-derived particlesand their precursors from the mid-latitudes in Eurasia orNorth America (Barrie 1986 Quinn et al 2007) Duringsummer the Arctic atmosphere is isolated from lower lati-tudes by the polar front (Iziomon et al 2006) Because cli-mate change is proceeding fastest in the high latitudes (Lawand Stohl 2007) and the Arctic Ocean waters could be animportant source of Arctic aerosols in summer there is anincreasing demand for better understanding the molecularcharacteristics and the sources of biogenic POA and SOAin the summertime Arctic atmosphere

The objective of this study is to investigate the chemi-cal speciation of both POA and SOA in the MBL over thesouthern Beaufort Sea Canadian Arctic More than 110 or-ganic compounds including aliphatic lipids anhydrosugarsprimary saccharides lignin and resin acids aromatic acidspolyacids sterols as well as polar organic tracer (eg 2-methyltetrols pinic acid andβ-caryophyllinic acid) for thephotooxidation of biogenic VOCs have been detected in themarine aerosols Their possible sources formation processesand the contributions of different organic compounds to or-ganic carbon (OC) are also discussed

2 Materials and methods

21 Sample collection

The FrancendashCanadandashUSA joint Arctic campaign MALINAwas conducted in the southern Beaufort Sea Canadian Arc-tic in summer 2009 Total suspended particulate (TSP) sam-ples (n = 10) were collected on a twondashthree day basis us-ing a high volume air sampler (Kimoto AS-810B) aboardthe icebreaker CCGSAmundsenon 3ndash25 August 2009 Onefield blank filter was performed by placing it in the samplerfor less than one minute without turning on the pump Allsamples were collected onto pre-combusted (450C for 6 h)quartz fiber filters (20times 25 cm Pallflex 2500QAT-UP) Thepump of the air sampler was switched onoff using a windspeed (gt5 m sminus1) and wind sector (plusmn 60deg) controller systemto avoid any potential contamination from the ship exhaustBefore the sampling filter was placed in a pre-combusted(450C for 6 h) glass jar with a Teflon-lined cap during thetransport and storage After the sampling the filter was re-covered into the glass jar transported to the laboratory andstored atminus20C prior to analysis







24 Analysis for OC










29

80

70

60 50oN

80

70

60

80

70

60

80

70

60

80

70

60

80 70

60

80

70

60

80

70

60

80

70

60

80

70

60


QFF3352

QFF3354

QFF3355

QFF3356

QFF3357

QFF3358

QFF3359

QFF3360

QFF3361

QFF3362

Cruise tracks

Sample ID

160oW 140 120 100 821 822




side 826

827









30

828

829



S1 832 833














31

QFF

3352

QFF

3354

QFF

3355

QFF

3356

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n (n

g m

-3)

834 835



838












32

QFF

3352

QFF

3354

QFF

3355

QFF

3356

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n (n

g m

-3) o

r Rat

io

839 840

841




845





33

QFF

3352

QFF

3354

QFF

3355

Q

FF33

56

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

Q

FF33

62

Rel

ativ

e ab

unda

nce

()

846 847


849



























34

0

2500

5000

0

005

01

0

15

3

0

20

40

0

15

3

0

004

008

(a) 2-Methyltetrols



(d) 2-MGA

(e) Sulfate

Con

cent

ratio

n (n

g m

-3)

[H+ ]

(microm

ol m

-3)

(f) Aerosol acidity

QFF

3352

Q

FF33

54

QFF

3355

Q

FF33

56

QFF

3357

Q

FF33

58

QFF

3359

Q

FF33

60

QFF

3361

Q

FF33

62

850

851



854




4 ] +

[NOminus

3 ] ndash [NH+




35

QFF

3352

QFF

3354

QFF

3355

QFF

3356

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n R

atio

855

856



859




36

y = 2992x + 0007 Rsup2 = 095 plt005 n=10

0

05

1

15

2

25

0 002 004 006 008


C5-

alke

ne tr

iols

(ng

m-3

)

860

861



864












37

QFF

3352

QFF

3354

QFF

3355

Q

FF33

56

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Rel

ativ

e ab

unda

nce

()

865

866





4 Conclusions








References

































































































24 Analysis for OC










29

80

70

60 50oN

80

70

60

80

70

60

80

70

60

80

70

60

80 70

60

80

70

60

80

70

60

80

70

60

80

70

60


QFF3352

QFF3354

QFF3355

QFF3356

QFF3357

QFF3358

QFF3359

QFF3360

QFF3361

QFF3362

Cruise tracks

Sample ID

160oW 140 120 100 821 822




side 826

827









30

828

829



S1 832 833














31

QFF

3352

QFF

3354

QFF

3355

QFF

3356

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n (n

g m

-3)

834 835



838












32

QFF

3352

QFF

3354

QFF

3355

QFF

3356

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n (n

g m

-3) o

r Rat

io

839 840

841




845





33

QFF

3352

QFF

3354

QFF

3355

Q

FF33

56

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

Q

FF33

62

Rel

ativ

e ab

unda

nce

()

846 847


849



























34

0

2500

5000

0

005

01

0

15

3

0

20

40

0

15

3

0

004

008

(a) 2-Methyltetrols



(d) 2-MGA

(e) Sulfate

Con

cent

ratio

n (n

g m

-3)

[H+ ]

(microm

ol m

-3)

(f) Aerosol acidity

QFF

3352

Q

FF33

54

QFF

3355

Q

FF33

56

QFF

3357

Q

FF33

58

QFF

3359

Q

FF33

60

QFF

3361

Q

FF33

62

850

851



854




4 ] +

[NOminus

3 ] ndash [NH+




35

QFF

3352

QFF

3354

QFF

3355

QFF

3356

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n R

atio

855

856



859




36

y = 2992x + 0007 Rsup2 = 095 plt005 n=10

0

05

1

15

2

25

0 002 004 006 008


C5-

alke

ne tr

iols

(ng

m-3

)

860

861



864












37

QFF

3352

QFF

3354

QFF

3355

Q

FF33

56

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Rel

ativ

e ab

unda

nce

()

865

866





4 Conclusions








References





























































































29

80

70

60 50oN

80

70

60

80

70

60

80

70

60

80

70

60

80 70

60

80

70

60

80

70

60

80

70

60

80

70

60


QFF3352

QFF3354

QFF3355

QFF3356

QFF3357

QFF3358

QFF3359

QFF3360

QFF3361

QFF3362

Cruise tracks

Sample ID

160oW 140 120 100 821 822




side 826

827









30

828

829



S1 832 833














31

QFF

3352

QFF

3354

QFF

3355

QFF

3356

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n (n

g m

-3)

834 835



838












32

QFF

3352

QFF

3354

QFF

3355

QFF

3356

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n (n

g m

-3) o

r Rat

io

839 840

841




845





33

QFF

3352

QFF

3354

QFF

3355

Q

FF33

56

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

Q

FF33

62

Rel

ativ

e ab

unda

nce

()

846 847


849



























34

0

2500

5000

0

005

01

0

15

3

0

20

40

0

15

3

0

004

008

(a) 2-Methyltetrols



(d) 2-MGA

(e) Sulfate

Con

cent

ratio

n (n

g m

-3)

[H+ ]

(microm

ol m

-3)

(f) Aerosol acidity

QFF

3352

Q

FF33

54

QFF

3355

Q

FF33

56

QFF

3357

Q

FF33

58

QFF

3359

Q

FF33

60

QFF

3361

Q

FF33

62

850

851



854




4 ] +

[NOminus

3 ] ndash [NH+




35

QFF

3352

QFF

3354

QFF

3355

QFF

3356

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n R

atio

855

856



859




36

y = 2992x + 0007 Rsup2 = 095 plt005 n=10

0

05

1

15

2

25

0 002 004 006 008


C5-

alke

ne tr

iols

(ng

m-3

)

860

861



864












37

QFF

3352

QFF

3354

QFF

3355

Q

FF33

56

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Rel

ativ

e ab

unda

nce

()

865

866





4 Conclusions








References





























































































30

828

829



S1 832 833














31

QFF

3352

QFF

3354

QFF

3355

QFF

3356

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n (n

g m

-3)

834 835



838












32

QFF

3352

QFF

3354

QFF

3355

QFF

3356

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n (n

g m

-3) o

r Rat

io

839 840

841




845





33

QFF

3352

QFF

3354

QFF

3355

Q

FF33

56

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

Q

FF33

62

Rel

ativ

e ab

unda

nce

()

846 847


849



























34

0

2500

5000

0

005

01

0

15

3

0

20

40

0

15

3

0

004

008

(a) 2-Methyltetrols



(d) 2-MGA

(e) Sulfate

Con

cent

ratio

n (n

g m

-3)

[H+ ]

(microm

ol m

-3)

(f) Aerosol acidity

QFF

3352

Q

FF33

54

QFF

3355

Q

FF33

56

QFF

3357

Q

FF33

58

QFF

3359

Q

FF33

60

QFF

3361

Q

FF33

62

850

851



854




4 ] +

[NOminus

3 ] ndash [NH+




35

QFF

3352

QFF

3354

QFF

3355

QFF

3356

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n R

atio

855

856



859




36

y = 2992x + 0007 Rsup2 = 095 plt005 n=10

0

05

1

15

2

25

0 002 004 006 008


C5-

alke

ne tr

iols

(ng

m-3

)

860

861



864












37

QFF

3352

QFF

3354

QFF

3355

Q

FF33

56

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Rel

ativ

e ab

unda

nce

()

865

866





4 Conclusions








References





























































































31

QFF

3352

QFF

3354

QFF

3355

QFF

3356

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n (n

g m

-3)

834 835



838












32

QFF

3352

QFF

3354

QFF

3355

QFF

3356

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n (n

g m

-3) o

r Rat

io

839 840

841




845





33

QFF

3352

QFF

3354

QFF

3355

Q

FF33

56

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

Q

FF33

62

Rel

ativ

e ab

unda

nce

()

846 847


849



























34

0

2500

5000

0

005

01

0

15

3

0

20

40

0

15

3

0

004

008

(a) 2-Methyltetrols



(d) 2-MGA

(e) Sulfate

Con

cent

ratio

n (n

g m

-3)

[H+ ]

(microm

ol m

-3)

(f) Aerosol acidity

QFF

3352

Q

FF33

54

QFF

3355

Q

FF33

56

QFF

3357

Q

FF33

58

QFF

3359

Q

FF33

60

QFF

3361

Q

FF33

62

850

851



854




4 ] +

[NOminus

3 ] ndash [NH+




35

QFF

3352

QFF

3354

QFF

3355

QFF

3356

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n R

atio

855

856



859




36

y = 2992x + 0007 Rsup2 = 095 plt005 n=10

0

05

1

15

2

25

0 002 004 006 008


C5-

alke

ne tr

iols

(ng

m-3

)

860

861



864












37

QFF

3352

QFF

3354

QFF

3355

Q

FF33

56

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Rel

ativ

e ab

unda

nce

()

865

866





4 Conclusions








References





























































































32

QFF

3352

QFF

3354

QFF

3355

QFF

3356

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n (n

g m

-3) o

r Rat

io

839 840

841




845





33

QFF

3352

QFF

3354

QFF

3355

Q

FF33

56

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

Q

FF33

62

Rel

ativ

e ab

unda

nce

()

846 847


849



























34

0

2500

5000

0

005

01

0

15

3

0

20

40

0

15

3

0

004

008

(a) 2-Methyltetrols



(d) 2-MGA

(e) Sulfate

Con

cent

ratio

n (n

g m

-3)

[H+ ]

(microm

ol m

-3)

(f) Aerosol acidity

QFF

3352

Q

FF33

54

QFF

3355

Q

FF33

56

QFF

3357

Q

FF33

58

QFF

3359

Q

FF33

60

QFF

3361

Q

FF33

62

850

851



854




4 ] +

[NOminus

3 ] ndash [NH+




35

QFF

3352

QFF

3354

QFF

3355

QFF

3356

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n R

atio

855

856



859




36

y = 2992x + 0007 Rsup2 = 095 plt005 n=10

0

05

1

15

2

25

0 002 004 006 008


C5-

alke

ne tr

iols

(ng

m-3

)

860

861



864












37

QFF

3352

QFF

3354

QFF

3355

Q

FF33

56

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Rel

ativ

e ab

unda

nce

()

865

866





4 Conclusions








References

















































































































34

0

2500

5000

0

005

01

0

15

3

0

20

40

0

15

3

0

004

008

(a) 2-Methyltetrols



(d) 2-MGA

(e) Sulfate

Con

cent

ratio

n (n

g m

-3)

[H+ ]

(microm

ol m

-3)

(f) Aerosol acidity

QFF

3352

Q

FF33

54

QFF

3355

Q

FF33

56

QFF

3357

Q

FF33

58

QFF

3359

Q

FF33

60

QFF

3361

Q

FF33

62

850

851



854




4 ] +

[NOminus

3 ] ndash [NH+




35

QFF

3352

QFF

3354

QFF

3355

QFF

3356

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n R

atio

855

856



859




36

y = 2992x + 0007 Rsup2 = 095 plt005 n=10

0

05

1

15

2

25

0 002 004 006 008


C5-

alke

ne tr

iols

(ng

m-3

)

860

861



864












37

QFF

3352

QFF

3354

QFF

3355

Q

FF33

56

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Rel

ativ

e ab

unda

nce

()

865

866





4 Conclusions








References





























































































35

QFF

3352

QFF

3354

QFF

3355

QFF

3356

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Con

cent

ratio

n R

atio

855

856



859




36

y = 2992x + 0007 Rsup2 = 095 plt005 n=10

0

05

1

15

2

25

0 002 004 006 008


C5-

alke

ne tr

iols

(ng

m-3

)

860

861



864












37

QFF

3352

QFF

3354

QFF

3355

Q

FF33

56

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Rel

ativ

e ab

unda

nce

()

865

866





4 Conclusions








References

































































































37

QFF

3352

QFF

3354

QFF

3355

Q

FF33

56

QFF

3357

QFF

3358

QFF

3359

QFF

3360

QFF

3361

QFF

3362

Rel

ativ

e ab

unda

nce

()

865

866





4 Conclusions








References

































































































References




























































































organic molecular composition of marine aerosols over the ......organic molecular composition of...

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