Agnès Borbon, M. Camredon, B. Aumont V. Michoud, S. Sauvage, S. Dusanter, N. Locoge V. Gros, N. Zannoni, C. Kalogridis, B. Bonsang M. Bocquet, C. Seigneur CARBO-SOR CARBOn within continental pollution plumes : SOurces and Reactivity

3 objectives Identify and quantify sources of primary and secondary gaseous organic carbon Composition and evolution of gaseous organic carbon in continental pollution plumes Atmospheric impact (reactivity and SOA) Posters : Michoud et al., Dusanter et al., Zannoni et al., Kalogridis et al.,

Methodology Modelling Inverse Source-receptor 0D box modelling Innovative instrumentation  Source-receptor approach : Europe and West Mediterranean One challenge Speciation of gaseous OC Coupled experimental methods CRM IMPiOVOC/GCMS Observations in Cap Corsica Secondary gaseous OC

Highlights Cape Corsica Air mass classification Reactivity == > see N. Zannoni’s talk Time series and multivariate analysis Lagrangian box modelling

Species groupSpecies name AVOCs methane, ethane, propane, n-butane, n-pentane, n-hexane, n-octane, n-nonane, n-undecane, n-dodecane, 2-methylpropane, 2-methylpentane, 2-methylhexane, 2,2- dimethylbutane, 2,2-dimethylpropane, …, ethylene, propylene, 1-butene, 2-methylpropene, 2-methyl-2-butene, 3- methyl-1-butene, 1,3-butadiene, trans-2-butene, cis-2-butene,.., benzene, toluene, ethylbenzene, styrene, m-xylene, o-xylene, p-xylene, acetylene, 1-butyne, acetonitrile. BVOCs isoprene, a-pinene, b-pinene, d-limonene, a-terpinene, b-terpinene, camphene. OVOCs acetaldehyde, formic acid, acetone, acetic acid, mglyox, methyl ethyl ketone, propionic acid, ethyl vinyl ketone, butiric acid, nopinone, pinonaldehyde, methacrolein, methyl vinyl ketone, formaldehyde, methanol. OthersNO, NO 2, CO. Cape Corsica > 80 species measured (NMHC, OVOC mono and multifunctional) Complementary techniques : on-line (GCFID/MS, PTR-TofMS, IMPIOVOC…) off-line

Low-levels of mixing ratios Dominated by OVOC Significant levels of biogenic VOCs (locally emitted) : typical levels for Mediterranean rural sites Cape Corsica

Air Mass Classification Back trajectories 48-h (HYSPLIT) 4 trajectoires / jour 3 criteria : origin, time since last contamination, photochemical clocks

Air Mass Classification Sector Source region Transport time FrequencyPeriod West S-France NW Spain 36h-48h30%20 & 24-28/07 North-EastN-Italy10h-20h20% 21-22/07 & 31/ /08 South Corsica Sardegna 12h-24h7%28-29/07 North-WestSE-France12h-18h4%30/07 Not all backtrajectories taken into account : homogeneity

Ageing At local scale : based on short-lived VOCs (BVOC and 1 st generation oxidation products) At the scale of long range transport : based on long-lived VOCS Jobson et al., JGR, 1994 Parrish et al., ± 5 min

Ageing At the scale of long range transport : based on long-lived VOCS β Urbain US Sidney, Tokyo Niwot ridge Atlantic ocean Point Arena

Ageing / Photochemical clocks At the scale of long range transport : based on long-lived VOCS W (>36 h processing) S NE (12-18h processing) NW

West SouthNorth EastNorth-West Time series Low frequency variations : anthropogenic + long-lived OVOC High frequency variations : primary and secondary biogenics Not only explained by air mass origin

West SouthNorth EastNorth-West Time series Ratios > 12-18h processing over sea Ratios < >36h processing over sea

PMF : 43 species (14 GC/FID/FID online, 22 PTRMS, 7 GC/FID/MS online) == > 329 observations Primary and secondary sources of gaseous OC 2 biogenic factors : one primary vs. one secondary Isoprene, Monoterpenes, Camphor … Correlated to T°C MVK, MACR, nopinone, pinonaldehyde … Correlated to T°C S W

Primary and secondary sources of gaseous OC 3 anthropogenic factors : ethane, acetylene… (k≈ 2-4x ) n-pentane, i-pentane… (k≈ 4x ) ethylene, propene, toluene… (k≈ 6x x )

Primary and secondary sources of gaseous OC One « oxygenated » factor : Carboxylic acids (formc, acetic, propanoïc, butyric) and other OVOC (methanol, acetone, acetaldehyde) Correlation with OA (R 2 = 0.48)

0D box modelling : continental plume scenario EMISSIONS DEPOSITION CHEMISTRY AND GAS-PHASE TRANSFERT Free troposphere Mixing layer Residual layer Emission Fluxes NO x, VOC, SO 2, CO F i =f (time, environnement) 183 species emitted species et reactions

0D box modelling : continental plume scenario OVOC hydrocarbons Gaseous OC dominated by OVOC (75%)

0D box modelling : continental plume scenario after 10 hours : OVOC hydrocarbons CO NO 2 NO 5 s -1

To conlude … in the frame of WP-2 Big efforts : instrumental development (CRM, IMPIOVOC, acids by PTR-ToFMS), laboratory analysis, QAQC Low levels, locally emitted biogenic fingerprint, dominance of OVOC (69%) == > intercomparison (OH reactivity, BVOC) == > unique, very detailed, complex database on gas OC To be completed for OVOC and SVOC Air mass classification : origin, transport time and aging Northern and Western sectors dominate ( 20% & 30% resp.) ; transport time > 1.5 days No systematic relationships between air mass origin and levels/composition of gaseous OC == > harmonization

To conlude … in the frame of WP-2 Multivariate analysis : Biogenic (primary/secondary) fingerprint, anthropogenic fingerprint as a function of lifetime, OVOC correlated to OA == > Joint analysis of VOC precursors/SOA by PMF 0D box modelling using GECKO-A generator : continental troposphere cas study Consistency between observations and model outputs (reactivity and OA mass concentration) at the time scale of transport time == > Support for data Ersa ( a posteriori analysis for OH reactivity)

About sources of gaseous OC … Koohkan, R.M., M. Bocquet, Y. Roustan, Y. Kim, C. Seigneur (2013). Estimation of volatile organic compound emissions for Europe using data assimilation, Atmos. Chem. Phys., 13, Inverse modelling : Statistical Inverse Modelling : see Michoud et al.’s poster

Thanks / Collaboration  Charbel Afif : (USJ, Beirut, Liban): IMPIOVOC development, field campaign  R. Berardo, E. Bon Nguyen, F. Chambraud, C.Gaimoz, A. Gratien, S. Oskanian, S. Morales, JM. Polienor, N. Touati (LISA, Créteil)  Guillaume Siour : extractions for 0D,  R. Sarda-Estève (LSCE)  PRIMEQUAL  ANR  ARMINES  ADEME  ChArMEx / MISTRALS  CEA-CNRS  EU-PIMMS