Les travaux présentés dans cette thèse portent premièrement sur la caractérisation de nouveaux photosensibilisateurs par des méthodes spectroscopiques. Ainsi les cinétiques de la réaction d'oxydation entre deux photosensibilisateurs à l'état triplet, imidazole-2-carboxaldehyde et 6-carboxypterine, et trois halogénures ont été déterminées par photolyse laser. La réactivité de l'état singulet de la 6- carboxypterine avec les halogénures et quatre acides organiques a été étudiée par fluorimétrie. Ces photosensibilisateurs sont relevants pour la photochimie à la surface de l'océan, mais également à la surface des particules atmosphériques. Les réactions mises en évidence mènent à la formation d'espèces radicalaires très réactives, influençant ainsi la composition de la phase condensée et gazeuse de l'environnement marin. La suite de cette étude s'est focalisée sur l'analyse des produits formés à partir de processus photo-induites à interface air-eau en présence d'une microcouche de surface d'un organique, utilisant deux organiques différents, l'octanol et l'acide nonanoique. En présence d'un photosensibilisateur et de lumière UVA, les changements en phase gaz ont été suivi par SRI-ToF-MS en ligne et en phase condensée par UPLC-(ESI)-HRMS. Ainsi on a démontré que la photochimie à la surface mène à la formation de produits fonctionnalisés et insaturés initiée par une abstraction d'hydrogène sur l'organique surfactant. Ces produits, observés en phase condensée et gazeuse, ont le potentiel de contribuer à la formation d'aérosols. Etonnamment, des produits ont également été observés dans les deux phases sans l'ajout d'un photosensibilisateur et montrant une activité photochimique de l'acide nonanoique seul à l'interface air-eau. Les mécanismes potentiels et les conséquences environnementales sont discutés / The works presented in this thesis concern firstly the characterization of two new photosensitizers by spectroscopic methods. This way the kinetics of the oxidation reaction between the triplet state of the photosensitizers, imidazole-2-carboxaldehyde and 6-carboxypterin, and three halides have been determined by laser flash photolysis. Also, the reactivity of the singlet state of 6-carboxypterin with halides and four organic acids has been studied by static fluorimetry. These photosensitizers are relevant for the photochemistry at the surface of the ocean, but also at the surface of atmospheric particles. The reactions evidenced by these studies lead to the formation of very reactive radical species influencing the composition of the condensed and gas phase of the marine environment. This study then focalized on the analysis of the products formed at the organic coated air-water interface through photo-induced processes. Two different organics were used as surfactants, octanol and nonanoic acid. In the presence of a photosensitizer and UVA light, the changes in the gas phase were monitored online by SRI-ToF-MS and in the condensed bulk phase by UPLC-(ESI)-HRMS offline analysis. These analysis showed that photochemical reactions at the interface lead to the formation of functionalized and unsaturated compounds initiated by a hydrogen abstraction on the organic surfactant. These products, observed in the condensed and gas phase have the potential to contribute to the formation of aerosols. Surprisingly, some of these products were also observed in the two phases without the presence of a photosensitizer, bringing into evidence a photochemistry of nonanoic acid at the air-water interface. Potential formation mechanisms of the products and environmental consequences are discussed

Particulate matter (PM) suspended in air varies in size from nanometers to micrometers and contains a wide range of chemical components, including organic compounds, black carbon (soot), inorganic minerals and metals. Atmospheric aerosols are generated from either primary sources like volcanic eruptions, re-suspended soil dust, sea spray, vegetative detritus, fossil fuel and biomass combustion emissions; or secondary atmospheric reactions via gas-to-particle conversion of atmospheric gases. Particle size, abundance, and chemical composition determine how a particle interacts with light and other atmospheric constituents (e.g. gases, water vapor) in addition to its impact on human health. While atmospheric scientists have been working on characterizing atmospheric aerosols for many years, major gaps persist in understanding the properties of many globally-important sources. This dissertation provides new understanding of the chemical composition of biomass burning and sea spray aerosols. PM emissions from biomass burning vary by fuel, and depend on fuel type and composition, moisture content, and combustion conditions. Although biomass smoke is critically important in global climate and local-regional health impacts, the physical and chemical composition of biomass burning aerosol is still not fully understood in the case of peat, agricultural residues and cooking fires. The Fire Laboratory at Missoula Experiments (FLAME) were designed to fulfill these gaps to improve our understanding in both historically undersampled and well-studied fuels while adding new instrumentation and experimental methods to provide previously unavailable information on chemical properties of biomass burning emissions. Globally-important biomass fuels were combusted in a controlled environment, and PM was chemically characterized to compute fuel based emission factors (EF) as the amount of chemical species released per unit mass of fuel burned. We showed that chemical composition of PM varies for different fuel types and certain fuels types (e.g., peat and ocote) emit considerably high concentrations of polycyclic aromatic compounds that are associated with negative health effects. We also showed that PM from biomass smoke contains fluoride for the first time, at approximately 0.1% by weight. With respect to the annual global emissions of PM due to biomass burning, this makes biomass burning an important source of fluoride to the atmosphere. Further, peatland fire emissions are one of the most understudied atmospheric aerosol sources but are a major source of greenhouse gases globally and cause severe air quality problems in Asia. This thesis provides the first field-based emissions characterization study, for samples collected at peat burning sites in Central Kalimantan, Indonesia. Using these EFs and estimates of the mass of fuel burned, it was estimated that 3.2 - 11 Tg of PM2.5 were emitted to atmosphere during 2015 El Niño peat fire episode which is ~10 % of estimated total annual PM flux for biomass burning. Overall, these studies computed more representative EFs for previously undersampled sources like peat, and previously unidentified chemical species like fluoride that can be used to update regional and global emission inventories. The concentration and composition of organic compounds in sea spray aerosol (SSA) alters its optical properties, hygroscopicity, cloud condensation, and ice nucleation properties and thus affects Earth’s radiative budget. In the past, SSA has been difficult to characterize, because of low concentrations relative to background pollutants. Nascent SSA was generated during a mesocosm, using a wave-flume at the University of California, San Diego and was characterized for saccharides and inorganic ions in order to assess their relative enrichment in fine (PM2.5) and coarse (PM10-2.5) SSA and sea surface microlayer (SSML) relative to seawater. For the first time, we showed that saccharides comprise a significant fraction of organic matter in fine and coarse SSA contributing 11 % and 27 %, respectively. Relative to sodium, saccharides were enriched 14-1314 times in fine SSA, 3-138 times in coarse SSA, but only up to 1.0-16.2 times in SSML. The saccharide and ion concentration in SSML and persistent whitecap foam was quantitatively assessed by another mesocosm study performed under controlled conditions. We demonstrated that relative to sodium, saccharides were enriched 1.7-6.4 times in SSML and 2.1-12 times in foam. Higher enrichment of saccharides in foam over the SSML indicates that surface active organic compounds become increasingly enriched on aged bubble film surfaces. Similarly, we showed that fine SSA contains saccharides characteristic of energy-related polysaccharides, while coarse SSA contains saccharides that are characteristic of structure-related polysaccharides. The ultrafiltration studies showed that structure-related polysaccharides effectively coagulate to form large particulate organic matter and size is likely the reason for their exclusion from small SSA. The enrichment of organic species in SSML, foam and SSA led to an enrichment of inorganic ions probably through chelation with organic molecules. Mean enrichment factors for major ions demonstrated the highest enrichment in fine SSA for potassium (1.3), magnesium (1.4), and calcium (1.7). Consequently, due to these organic and inorganic enrichments, SSA develops a significantly different chemical profile compared to seawater. These improved chemical profiles of SSA should be used to develop laboratory proxies to further study the transfer of organic matter across the ocean-air interface and the physical properties of SSA. . Overall, the results presented in this dissertation provide new chemical profiles for previously understudied emission sources like peatland fire emissions, and previously unquantified chemical species like F- in biomass burning emissions and enrichment of saccharides and ions in SSA. These data could be used in updating regional and global emission inventories, atmospheric modeling and human exposure studies.

Glancing angle laser induced fluorescence was used to monitor the kinetics of the photodegradation of chlorophyll at the surface of various salt solutions. The loss was measured using varying wavelengths of actinic radiation in the presence and absence of gas phase ozone. The loss rate of illuminated chlorophyll was faster on salt water surfaces than fresh water surfaces, both in the presence and absence of ozone. On salt water surfaces, the dependence of the loss rate on [O3(g)] was different under illuminated conditions than in the dark. This was further investigated by measuring the excitation spectra and the dependence of chlorophyll loss on the concentration of salts at the salt water surface. The possible production of reactive halogen atoms is the likely reason for the observed enhancement. The following results provide evidence of photosensitized oxidation of halogen anions, in the UV-visible range of the spectrum, resulting in halogen atom release.

Glancing angle laser induced fluorescence was used to monitor the kinetics of the photodegradation of chlorophyll at the surface of various salt solutions. The loss was measured using varying wavelengths of actinic radiation in the presence and absence of gas phase ozone. The loss rate of illuminated chlorophyll was faster on salt water surfaces than fresh water surfaces, both in the presence and absence of ozone. On salt water surfaces, the dependence of the loss rate on [O3(g)] was different under illuminated conditions than in the dark. This was further investigated by measuring the excitation spectra and the dependence of chlorophyll loss on the concentration of salts at the salt water surface. The possible production of reactive halogen atoms is the likely reason for the observed enhancement. The following results provide evidence of photosensitized oxidation of halogen anions, in the UV-visible range of the spectrum, resulting in halogen atom release.

Under low wind speed conditions, surfactants accumulate at the air-sea interface, dampen short-gravity capillary (Bragg) waves, and form natural sea slicks that are detectable visually and in synthetic aperture radar (SAR) imagery. Marine organisms, such as phytoplankton, zooplankton, seaweed, and bacteria, produce and degrade surfactants during various life processes. This study coordinates in situ sampling with TerraSAR-X satellite overpasses in order to help guide microbiological analysis of the sea surface microlayer (SML) and associated subsurface water (SSW). Samples were collected in the Gulf of Mexico during a research cruise (LASER) in February 2016 to determine abundance of surfactant associated bacteria in the sea surface microlayer and subsurface water column. By using real time polymerase chain reaction (quantitative PCR, or qPCR) to target Bacillus spp. associated with surfactant production, results indicate that more surfactant-associated bacteria reside in the subsurface water in low wind speed conditions. Sequencing results suggest that Bacillus and Pseudomonas are more abundant in the SSW in low wind speed conditions. These results indicate that these bacteria reside in the SSW, presumably producing surfactants that move to the surface via physical processes, accumulate on and enrich the sea surface microlayer.

No description available.

Primary marine aerosol particles containing biogenic polymer microgels play a potential role for cloud formation in the pristine high Arctic summer. One of the major sources of the polymer gels in Arctic aerosol was suggested to be the surface water and more specifically, the surface microlayer (SML) of the open leads within the perennial sea ice as a result of bubble bursting at the air-sea interface.  Phytoplankton and/or ice algae are believed to be the main origins of the polymer gels. In this thesis, we examine the chemical composition of biogenic polymers, with focus on polysaccharides, in seawater and airborne aerosol particles collected during the Arctic Summer Cloud Ocean Study (ASCOS) in the summer of 2008. The main results and findings include: A novel method using liquid chromatography coupling with tandem mass spectrometry was developed and applied for identification and quantification of polysaccharides. The enrichment of polysaccharides in the SML was shown to be a common feature of the Arctic open leads. Rising bubbles and surface coagulation of polymers are the likely mechanism for the accumulation of polysaccharides at the SML. The size dependencies of airborne polysaccharides on the travel-time since the last contact with the open sea are indicative of a submicron microgel source within the pack ice.  The similarity of polysaccharides composition observed between the ambient aerosol particles and those generated by in situ bubbling experiments confines the microgel source to the open leads. The demonstrated occurrence of polysaccharides in surface sea waters and in air, with surface-active and hygroscopic properties, has shown their potential to serve as cloud condensation nuclei and subsequently promote cloud-drop activation in the pristine high Arctic. Presumably this possibility may renew interest in the complex but fascinating interactions between marine biology, aerosol, clouds and climate. / At the time of doctoral defence, the following paper was unpublished and had a status as follows: Paper 4: Manuscript

The sea-surface microlayer (SML) is the boundary layer at the air-sea interface where many biogeochemical processes occur. Many organisms (e.g., bacteria) produce surface active agents (surfactants) for life processes, which accumulate in the SML and dampen short gravity-capillary waves, resulting in sea surface slicks. Synthetic aperture radar (SAR) is capable of remotely sensing these features on the sea surface by measuring reflected backscatter from the ocean surface in microwaves. This study coordinates SAR overpasses with in situ SML and subsurface (SSW) microbial sample collection to guide subsequent analysis after 16s rRNA sequencing on the Illumina MiSeq. In April 2017, 138 SML and SSW samples were collected near a targeted oil-seep where the Taylor Platform was knocked down in the Gulf of Mexico, both in and out of visually-observed oil slicks. In July and August 2018, 220 SML and SSW samples were collected near the Looe Key coral reef and a coastal seagrass area. Analysis of microbial abundance and diversity between the two experiments shows that within oil slicks, surfactant- and oil-associated bacteria prefer to reside within the SSW rather than in the SML. In natural slicks in the coastal seagrass area, these bacteria are more abundant in the SML. Outside of these slicks, surfactant-associated bacteria are more abundant within the SML than the SSW. This suggests that the presence of oil reduces the habitability of the SML, whereas natural slicks created by foam and other surfactants creates a more habitable environment in the SML. With lower wind speed, abundance of these bacteria are greater, as increased wind speed results in a harsher environment. The diurnal cycle had an effect on the relative abundance of surfactant-associated bacteria in the SML and SSW. Our results demonstrate the usefulness of synthetic aperture radar to remotely sense sea surface slicks in coordination with in situ surfactant-associated bacteria data collection of the sea surface slicks.

Primär emittierte marine Aerosolpartikel haben einen wichtigen Einfluss auf den Strahlungshaushalt der Erde, indem sie unter anderem als Kondensations (CCN)- oder Eiskeime (INP) für die Bildung von Wolken wirken. In den ozeanisch geprägten Polarregionen dominieren diese marinen Aerosolpartikel in der Luft und können dort eine bedeutende bzw. sich noch verändernde Rolle im Rahmen des Klimawandels einnehmen. Sie entspringen vordergründig aus dem ozeanische Oberflächenwasser und dem hauchdünnen Oberflächenfilm, dem sogenannte sea surface microlayer (SML), und werden durch das Platzen von durch Wind eingetragene Luftblasen freigesetzt. Primär emittierte marine Aerosolpartikel bestehen aus anorganischem Meersalz und organischen Kohlenstoffverbindungen, deren relative Anteile sich stark in Abhängigkeit vom Aerosoldurchmessers unterscheiden. In diesem Zusammenhang stellen die marinen Kohlenhydrate eine wichtige organische Stoffgruppe dar, deren ozeanische Quellen, Übergang vom Ozean in die Atmosphäre, Veränderungen in der Atmosphäre als auch deren Beitrag bei der Kondensation und Eiskeimbildung noch nicht ausreichend verstanden sind. Dieser begrenzte Kenntnisstand ist unter anderem auf das mangelnde Vorhandensein analytischer Methoden zurückzuführen, die eine zuverlässige Bestimmung von Kohlenhydraten in den stark salzhaltigen Matrices bei sehr niedrigen Massekonzentrationen mit hohen Wiederfindungsraten gewährleisten. Im Rahmen dieser Doktorarbeit wurde durch Kombination der Hochleistungs-Anionenaustauschchromatographie mit gepulster amperometrischer Detektion (HPAEC-PAD) und einer Entsalzung durch Elektrodialyse eine analytische Methode entwickelt, welche die Bestimmung eines breiten Spektrums an gelösten Kohlenhydraten in freier (als Monosaccharide) und gebundener (als Oligo- oder Polysaccharide) Form in Meerwasser und anderen salzhaltigen Matrices ermöglicht. Mithilfe dieser neuen Methode wurde ein biogeochemischer Zusammenhang zwischen dem Vorkommen von freier Glucose und der eiskeimbildenden Aktivität im arktischen SML beobachtet. Außerdem wurde im meereisfreien Teil des Südlichen Ozeans der primäre Transfer von Kohlenhydraten vom Ozean über den SML in die Atmosphäre und deren sekundäre atmosphärische Veränderungen erforscht. Die umfangreichen Untersuchungen mariner Kohlenhydrate in polarem Meerwasser und Aerosolpartikeln zeigen Indizien einer bisher noch unterschätzten atmosphärischen Bedeutung mikrobiologischer Prozesse auf.:1. Introduction ............................................................................................................................................... 1 1.1 The Polar Oceans ................................................................................................................................. 3 1.1.1 Geographical Definitions and Characteristics.......................................................................... 3 1.1.2 Role in Earth’s Climate System ................................................................................................ 5 1.1.3 Changing Climate and Consequences ...................................................................................... 6 1.2 Sea Spray Aerosol over the Polar Oceans ........................................................................................... 9 1.2.1 Production Mechanisms of Sea Spray Aerosol ........................................................................ 9 1.2.2 Chemo-Selective Sea-Air Transfer and Atmospheric Aging ................................................... 10 1.2.3 Impact on Earth’s Radiation Budget ...................................................................................... 12 1.3 The Surface of the Polar Oceans ....................................................................................................... 15 1.3.1 The Sea Surface Microlayer ................................................................................................... 15 1.3.2 Selective Enrichment of Chemical Compounds ..................................................................... 15 1.3.3 Atmospheric Relevance for Atmospheric Chemistry and Cloud Microphysics ..................... 24 1.4 Marine Carbohydrates....................................................................................................................... 26 1.4.1 Chemical Structures ............................................................................................................... 26 1.4.2 Microbial Role ........................................................................................................................ 28 1.4.3 Marine Carbohydrates in the Atmosphere ............................................................................ 30 1.4.4 Chemical Analysis and Sea Salt Interference ......................................................................... 31 2. Results and Discussions ........................................................................................................................... 35 2.1 First Publication ................................................................................................................................. 35 2.1.1 Glucose as a Potential Chemical Marker for Ice Nucleating Activity in Arctic Seawater and Melt Pond Samples ......................................................................................................................... 35 2.1.2 Supporting Information ......................................................................................................... 47 2.2 Second Publication ............................................................................................................................ 55 A protocol for quantifying mono-and polysaccharides in seawater and related saline matrices by electro-dialysis (ED) – combined with HPAEC-PAD ........................................................................ 55 2.3 Third Publication ............................................................................................................................... 70 2.3.1 Aerosol Marine Primary Carbohydrates and Atmospheric Transformation in the Western Antarctic Peninsula ......................................................................................................................... 70 2.3.2 Supporting Information ......................................................................................................... 88 3. Atmospheric Implications ........................................................................................................................ 95 4. Summary ................................................................................................................................................ 98 5. References ............................................................................................................................................. 101 List of Abbreviations .................................................................................................................................. 121 List of Figures ............................................................................................................................................. 123 List of Tables .............................................................................................................................................. 124 Curriculum Vitae ........................................................................................................................................ 125 / Primary marine aerosol particles impact Earth’s radiation budget by acting, among other things, as cloud condensation nuclei (CCN) or ice nucleating particles (INP) for the formation of clouds. Over the polar oceans, primary marine aerosol emissions dominate the atmospheric particles and can play a significant and changing role there in the context of climate change. These particles are primarily emitted from the oceanic surface water and a thin surface film, the so-called sea surface microlayer (SML), by the bursting of air bubbles entrained by the wind. They consist of inorganic sea salt and organic matter (OM), whose relative proportions differ greatly depending on the aerosol diameter. In this context, the marine carbohydrates represent an important group of OM, whose oceanic sources, their transition from the sea to the atmosphere, atmospheric aging and contribution to the condensation of water droplets and ice nucleation are not well understood. This limited level of knowledge is due, among other things, to the lack of analytical methods that enable a reliable determination of carbohydrates at very low mass concentrations with high recovery rates in the salty matrices. Within the framework of this PhD thesis, an analytical method was developed by combining high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD) and a prior desalination by electro-dialysis (ED), which enables the determination of a wide range of dissolved carbohydrates in their free (as monosaccharides) and combined (as oligo- or polysaccharides) forms in seawater and other saline matrices. With this new method, a biogeochemical connection between the presence of free glucose and the ice nucleating activity in the Arctic SML could be observed. In addition, the primary transfer of carbohydrates from the ocean via the SML into the atmosphere and subsequent secondary atmospheric transformations were investigated in the sea ice-free part of the Southern Ocean. Consequently, the extensive investigations of marine carbohydrates in seawater and aerosol particles indicate an atmospheric importance of microbiological processes that has been underestimated until now.:1. Introduction ............................................................................................................................................... 1 1.1 The Polar Oceans ................................................................................................................................. 3 1.1.1 Geographical Definitions and Characteristics.......................................................................... 3 1.1.2 Role in Earth’s Climate System ................................................................................................ 5 1.1.3 Changing Climate and Consequences ...................................................................................... 6 1.2 Sea Spray Aerosol over the Polar Oceans ........................................................................................... 9 1.2.1 Production Mechanisms of Sea Spray Aerosol ........................................................................ 9 1.2.2 Chemo-Selective Sea-Air Transfer and Atmospheric Aging ................................................... 10 1.2.3 Impact on Earth’s Radiation Budget ...................................................................................... 12 1.3 The Surface of the Polar Oceans ....................................................................................................... 15 1.3.1 The Sea Surface Microlayer ................................................................................................... 15 1.3.2 Selective Enrichment of Chemical Compounds ..................................................................... 15 1.3.3 Atmospheric Relevance for Atmospheric Chemistry and Cloud Microphysics ..................... 24 1.4 Marine Carbohydrates....................................................................................................................... 26 1.4.1 Chemical Structures ............................................................................................................... 26 1.4.2 Microbial Role ........................................................................................................................ 28 1.4.3 Marine Carbohydrates in the Atmosphere ............................................................................ 30 1.4.4 Chemical Analysis and Sea Salt Interference ......................................................................... 31 2. Results and Discussions ........................................................................................................................... 35 2.1 First Publication ................................................................................................................................. 35 2.1.1 Glucose as a Potential Chemical Marker for Ice Nucleating Activity in Arctic Seawater and Melt Pond Samples ......................................................................................................................... 35 2.1.2 Supporting Information ......................................................................................................... 47 2.2 Second Publication ............................................................................................................................ 55 A protocol for quantifying mono-and polysaccharides in seawater and related saline matrices by electro-dialysis (ED) – combined with HPAEC-PAD ........................................................................ 55 2.3 Third Publication ............................................................................................................................... 70 2.3.1 Aerosol Marine Primary Carbohydrates and Atmospheric Transformation in the Western Antarctic Peninsula ......................................................................................................................... 70 2.3.2 Supporting Information ......................................................................................................... 88 3. Atmospheric Implications ........................................................................................................................ 95 4. Summary ................................................................................................................................................ 98 5. References ............................................................................................................................................. 101 List of Abbreviations .................................................................................................................................. 121 List of Figures ............................................................................................................................................. 123 List of Tables .............................................................................................................................................. 124 Curriculum Vitae ........................................................................................................................................ 125

Species must interact with air—aqueous interfaces in order to transport between either phase, however organic coated water surfaces are ubiquitous in the environment, and the physical and chemical processes that occur at organic coated aqueous surfaces are often different than those at pure air—water interfaces. Three studies were performed investigating the transport of species across air—aqueous interfaces with organic coatings in an effort to gain further insight into these processes. Gas and solution phase absorption spectroscopy were used to study the effect of octanol coatings on the formation of molecular iodine (I2) by the heterogeneous ozonation of iodide and its partitioning between phases. Compared to uncoated solutions, the presence of octanol monolayers had a minor effect on the total amount of I2 produced, however, it did significantly enhance the gas to solution partitioning of I2. Incoherent broadband cavity-enhanced absorption spectroscopy (IBBC-EAS) was used to measure the gas-phase nitrogen dioxide (NO2) evolved via photolysis of aqueous nitrate solutions either uncoated or containing octanol, octanoic acid and stearic acid monolayers. Both octanol and stearic acid reduced the rate of gaseous NO2 evolution, and octanol also decreased the steady-state amount of gaseous NO2. Alternatively, octanoic acid enhanced the rate of gaseous NO2 evolution. Finally, the loss of aqueous carbon dioxide (CO2) from aqueous solutions saturated with CO2 was measured using a CO2 electrode in the absence and presence of stearic acid monolayers and octanol coatings, and a greenhouse gas analyzer was used to measure the evolution of gaseous CO2 from solutios with octanol monolayers. Enhanced losses of aqueous and evolved gaseous CO2 were observed with organic coated solutions compared to those uncoated. The results of these studies suggest that organic coatings influence the transport of I2, NO2 and CO2 via one, or a combination of: barrier effects, surface tension effects, chemistry effects and aqueous – surface – gas partitioning effects. These results, particularly the enhanced partitioning of these species to octanol coated aqueous surfaces, have important implications for species transport at air—aqueous interfaces, and may provide useful insight for future studies and parameters for atmospheric models of these species.