The Ocean's Vital Skin: Toward an Integrated Understanding of the Sea Surface Microlayer

Frontiers in Marine Science, Journal Year: 2017, Volume and Issue: 4

Published: May 30, 2017

Despite the huge extent of ocean's surface, until now relatively little attention has been paid to sea surface microlayer (SML) as ultimate interface where heat, momentum and mass exchange between ocean atmosphere takes place. Via SML, large-scale environmental changes in such warming, acidification, deoxygenation eutrophication potentially influence cloud formation, precipitation global radiation balance. Due deep connectivity biological, chemical physical processes, studies SML may reveal multiple sensitivities regional changes. Understanding processes at particular involving an important determinant interface, could therefore provide essential contribution reduction uncertainties regarding ocean-climate feedbacks. This review identifies gaps our current knowledge highlights a need develop holistic mechanistic understanding diverse occurring ocean-atmosphere interface. We advocate development strong interdisciplinary expertise collaboration order bridge atmospheric sciences. Although this will pose significant methodological challenges, initiative would represent new role model for research Earth System

Language: Английский

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Microlayer source of oxygenated volatile organic compounds in the summertime marine Arctic boundary layer

Proceedings of the National Academy of Sciences, Journal Year: 2017, Volume and Issue: 114(24), P. 6203 - 6208

Published: May 30, 2017

Summertime Arctic shipboard observations of oxygenated volatile organic compounds (OVOCs) such as acids, key precursors climatically active secondary aerosol (SOA), are consistent with a novel source OVOCs to the marine boundary layer via chemistry at sea surface microlayer. Although this has been studied in laboratory setting, acid emissions from microlayer have not previously observed ambient environments. Correlations between measurements OVOCs, including high levels formic acid, atmosphere (measured by an online high-resolution time-of-flight mass spectrometer) and dissolved matter ocean point for measured OVOCs. That is photomediated indicated correlations diurnal cycles OVOC solar radiation. In contrast, do correlate isoprene, monoterpenes, or dimethyl sulfide. Results box model calculations heterogeneous As ice retreats carbon inputs increase, impact on summer likely increase. Globally, should be assessed other environments quantify its SOA burdens atmosphere, ultimately climate.

Language: Английский

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Sea spray aerosol chemical composition: elemental and molecular mimics for laboratory studies of heterogeneous and multiphase reactions

Chemical Society Reviews, Journal Year: 2018, Volume and Issue: 47(7), P. 2374 - 2400

Published: Jan. 1, 2018

Schematic representation of the reactive uptake N₂O₅to a sea spray aerosol particle containing thick organic film.

Language: Английский

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Atmospheric photochemistry at a fatty acid–coated air-water interface

Science, Journal Year: 2016, Volume and Issue: 353(6300), P. 699 - 702

Published: Aug. 11, 2016

Active fatty acid layers Saturated acids are considered to be inert, but they can surprisingly reactive when present as a coating at an air-water interface. Rossignol et al. show that nonanoic is photochemically active it monolayer on water surface (see the Perspective by Vaida). Fatty ubiquitous in environment, and their photochemical processing could have substantial impact local ozone particle formation. Science , this issue p. 699 ; see also 650

Language: Английский

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Unravelling New Processes at Interfaces: Photochemical Isoprene Production at the Sea Surface

Environmental Science & Technology, Journal Year: 2015, Volume and Issue: 49(22), P. 13199 - 13205

Published: Sept. 10, 2015

Isoprene is an important reactive gas that produced mainly in terrestrial ecosystems but also marine ecosystems. In the environment, isoprene seawater by various biological processes. Here, we show photosensitized reactions involving sea-surface microlayer lead to production of significant amounts isoprene. It suggested H-abstraction processes are initiated photochemically excited dissolved organic matter which will degrade fatty acids acting as surfactants. This chemical interfacial processing may represent a abiotic source boundary layer.

Language: Английский

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Atmospheric chemistry of bioaerosols: heterogeneous and multiphase reactions with atmospheric oxidants and other trace gases

Chemical Science, Journal Year: 2016, Volume and Issue: 7(11), P. 6604 - 6616

Published: Jan. 1, 2016

Once airborne, biologically-derived aerosol particles are prone to reaction with various atmospheric oxidants such as OH, NO₃, and O₃.

Language: Английский

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First Measurements of Organic Triplet Excited States in Atmospheric Waters

Environmental Science & Technology, Journal Year: 2018, Volume and Issue: 52(9), P. 5218 - 5226

Published: April 3, 2018

Photooxidants chemically transform organic compounds in atmospheric drops and particles. such as hydroxyl radical (•OH) singlet molecular oxygen (1O2*) have been characterized cloud fog drops, but there are no measurements of the triplet excited states matter (3C*). These "triplets", which formed from excitation chromophoric dissolved (CDOM), i.e., brown carbon, difficult to measure because they a mixture species instead single entity. Here, we use two-probe technique steady-state concentrations, rates photoformation, quantum yields oxidizing during simulated-sunlight illumination bulk waters. Concentrations 3C* (0.70–15) × 10–14 M with an average (±σ) value 5.0 (±5.1) M. The photoformation rate is 130 (±130) μM h–1, while yield 3.7 (±4.5)%. Based on our previous •OH 1O2* same samples, ratio concentrations for 1O2*:3C*:•OH approximately 3:1:0.04, respectively. At measured can be dominant aqueous oxidants phenols biomass combustion.

Language: Английский

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Sunlight as an energetic driver in the synthesis of molecules necessary for life

Physical Chemistry Chemical Physics, Journal Year: 2016, Volume and Issue: 18(30), P. 20067 - 20084

Published: Jan. 1, 2016

Solar radiation was overwhelmingly the largest source of energy on early Earth. Energy provided by Sun has potential to access different chemistries than other sources, such as hydrothermal vents, because unique characteristics photochemistry that differentiate it from conventional thermal chemistry. This review considers how sunlight-driven reactions can abiotically generate prebiotic molecules necessary for evolution life. We discuss briefly and likely environmental conditions Earth is both environment- molecule-specific. An overview fundamental principles photophysics followed discussion a selection prebiotically-relevant examples photochemical reactions, focusing syntheses lead production cellular components (e.g. sugars, lipids, biopolymer precursors). The role photostability an evolutionary driving force also considered. These highlight ability simple organic harness solar convert into high-energy chemical bonds, generating molecular complexity.

Language: Английский

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First Quantification of Imidazoles in Ambient Aerosol Particles: Potential Photosensitizers, Brown Carbon Constituents, and Hazardous Components

Environmental Science & Technology, Journal Year: 2016, Volume and Issue: 50(3), P. 1166 - 1173

Published: Jan. 4, 2016

Imidazoles are widely discussed in recent literature. They have been studied as a secondary product of the reaction dicarbonyls with nitrogen containing compounds number laboratory studies, potentially acting photosensitizers triggering organic aerosol growth and forming constituents light absorbing brown carbon. Despite knowledge from no quantitative information about imidazoles ambient particles is available. Within present study, five (1-butylimidazole, 1-ethylimidazole, 2-ethylimidazole, imidazol-2-carboxaldehyde, 4(5)-methylimidazole) were successfully identified quantified for first time samples different environments Europe China. Their concentrations range between 0.2 14 ng/m3. 4(5)-Methylimidazole was found to be most abundant imidazole. The occurrence seems favored at sites strong biomass burning influence or connected more polluted air masses. No connection particle pH imidazole concentration. Our work corroborates studies by showing that measurable amounts. Moreover, it further motivates explore potential photosensitizing properties small alkyl-substituted imidazoles.

Language: Английский

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Evidence for superiority of conventional adsorbents in the sorptive removal of gaseous benzene under real-world conditions: Test of activated carbon against novel metal-organic frameworks

Journal of Cleaner Production, Journal Year: 2019, Volume and Issue: 235, P. 1090 - 1102

Published: July 5, 2019

Language: Английский

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