Marine Bacteria Affect Saccharide Enrichment in Sea Spray Aerosol during a Phytoplankton Bloom

Four North Atlantic Aerosol and Marine Ecosystems Study (NAAMES) field campaigns from winter 2015 through spring 2018 sampled an extensive set of oceanographic and atmospheric parameters during the annual phytoplankton bloom cycle. This unique dataset provides four seasons of open-ocean observations of wind speed, sea surface temperature (SST), seawater particle attenuation at 660 nm (cp,660, a measure of ocean particulate organic carbon), bacterial production rates, and sea-spray aerosol size distributions and number concentrations (NSSA). The NAAMES measurements show moderate to strong correlations (0.56 < R < 0.70) between NSSA and local wind speeds in the marine boundary layer on hourly timescales, but this relationship weakens in the campaign averages that represent each season, in part because of the reduction in range of wind speed by multiday averaging. NSSA correlates weakly with seawater cp,660 (R = 0.36, P << 0.01), but the correlation with cp,660, is improved (R = 0.51, P < 0.05) for periods of low wind speeds. In addition, NAAMES measurements provide observational dependence of SSA mode diameter (dm) on SST, with dm increasing to larger sizes at higher SST (R = 0.60, P << 0.01) on hourly timescales. These results imply that climate models using bimodal SSA parameterizations to wind speed rather than a single SSA mode that varies with SST may overestimate SSA number concentrations (hence cloud condensation nuclei) by a factor of 4 to 7 and may underestimate SSA scattering (hence direct radiative effects) by a factor of 2 to 5, in addition to overpredicting variability in SSA scattering from wind speed by a factor of 5.

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A Dynamic Link between Ice Nucleating Particles Released in Nascent Sea Spray Aerosol and Oceanic Biological Activity during Two Mesocosm Experiments

Journal of the Atmospheric Sciences ◽

10.1175/jas-d-16-0087.1 ◽

2017 ◽

Vol 74 (1) ◽

pp. 151-166 ◽

Cited By ~ 46

Author(s):

Christina S. McCluskey ◽

Thomas C. J. Hill ◽

Francesca Malfatti ◽

Camille M. Sultana ◽

Christopher Lee ◽

...

Keyword(s):

Biological Activity ◽

Heterotrophic Bacteria ◽

Phytoplankton Bloom ◽

Sea Spray ◽

Emission Rates ◽

Phytoplankton Blooms ◽

Aerosol Composition ◽

Chl A ◽

Mesocosm Experiments ◽

Sea Spray Aerosol

Abstract Emission rates and properties of ice nucleating particles (INPs) are required for proper representation of aerosol–cloud interactions in atmospheric models. Few investigations have quantified marine INP emissions, a potentially important INP source for remote oceanic regions. Previous studies have suggested INPs in sea spray aerosol (SSA) are linked to oceanic biological activity. This proposed link was explored in this study by measuring INP emissions from nascent SSA during phytoplankton blooms during two mesocosm experiments. In a Marine Aerosol Reference Tank (MART) experiment, a phytoplankton bloom was produced with chlorophyll-a (Chl a) concentrations reaching 39 μg L−1, while Chl a concentrations more representative of natural ocean conditions were obtained during the Investigation into Marine Particle Chemistry and Transfer Science (IMPACTS; peak Chl a of 5 μg L−1) campaign, conducted in the University of California, San Diego, wave flume. Dynamic trends in INP emissions occurred for INPs active at temperatures > −30°C. Increases in INPs active between −25° and −15°C lagged the peak in Chl a in both studies, suggesting a consistent population of INPs associated with the collapse of phytoplankton blooms. Trends in INP emissions were also compared to aerosol composition, abundances of microbes, and enzyme activity. In general, increases in INP concentrations corresponded to increases in organic species in SSA and the emissions of heterotrophic bacteria, suggesting that both microbes and biomolecules contribute to marine INP populations. INP trends were not directly correlated with a single biological marker in either study. Direct measurements of INP chemistry are needed to accurately identify particles types contributing to marine INP populations.

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Sea Spray Aerosol Chamber Study on Selective Transfer and Enrichment of Free and Combined Amino Acids

ACS Earth and Space Chemistry ◽

10.1021/acsearthspacechem.1c00080 ◽

2021 ◽

Author(s):

Nadja Triesch ◽

Manuela van Pinxteren ◽

Matthew Salter ◽

Christian Stolle ◽

Ryan Pereira ◽

...

Keyword(s):

Amino Acids ◽

Sea Spray ◽

Selective Transfer ◽

Chamber Study ◽

Sea Spray Aerosol ◽

Aerosol Chamber

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Linking variations in sea spray aerosol particle hygroscopicity to composition during two microcosm experiments

10.5194/acp-2016-36 ◽

2016 ◽

Author(s):

Sara D. Forestieri ◽

Gavin C. Cornwell ◽

Taylor M. Helgestad ◽

Kathryn A. Moore ◽

Christopher Lee ◽

...

Keyword(s):

Light Scattering ◽

Relative Humidity ◽

Salt Content ◽

Sea Salt ◽

Sea Spray ◽

Hygroscopic Growth ◽

Phytoplankton Blooms ◽

Aerosol Composition ◽

Sea Spray Aerosol ◽

Indoor And Outdoor

Abstract. The extent to which water uptake influences the light scattering ability of marine sea spray aerosol (SSA) particles depends critically on SSA chemical composition. The organic fraction of SSA can increase during phytoplankton blooms, decreasing the salt content and therefore the hygroscopicity of the particles. In this study, subsaturated hygroscopic growth factors at 85 % relative humidity (GF(85 %)) of SSA particles were quantified during two induced phytoplankton blooms in marine aerosol reference tanks (MARTs). One MART was illuminated with fluorescent lights and the other was illuminated with sunlight, referred to as the "indoor" and "outdoor" MARTs, respectively. GF(85 %) values for SSA particles were derived from measurements of light scattering and particle size distributions, concurrently with online single particle and bulk aerosol composition measurements. During both microcosm experiments, the observed bulk average GF(85 %) values were depressed substantially relative to pure, inorganic sea salt, by 10 to 19 %, with a one (indoor MART) and six (outdoor MART) day lag between GF(85 %) depression and the peak chlorophyll-a concentrations. The fraction of organiccontaining SSA particles generally increased after the peak of the phytoplankton blooms. The GF(85 %) values were inversely correlated with the fraction of particles containing organic or other biological markers. This indicates these particles were less hygroscopic than the particles identified as predominately sea salt containing and demonstrates a clear relationship between SSA particle composition and the sensitivity of light scattering to variations in relative humidity. The implications of these observations to the direct climate effects of SSA particles are discussed.

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Gaseous chemistry and aerosol mechanism developments for version 3.5.1 of the online regional model, WRF-Chem

Geoscientific Model Development ◽

10.5194/gmd-7-2557-2014 ◽

2014 ◽

Vol 7 (6) ◽

pp. 2557-2579 ◽

Cited By ~ 30

Author(s):

S. Archer-Nicholls ◽

D. Lowe ◽

S. Utembe ◽

J. Allan ◽

R. A. Zaveri ◽

...

Keyword(s):

Gas Phase ◽

Chemical Mechanism ◽

Reduced Form ◽

Sea Spray ◽

Wind Fields ◽

Aerosol Composition ◽

Aerosol Emission ◽

Sea Spray Aerosol ◽

The Impact ◽

Phase Chemical

Abstract. We have made a number of developments to the Weather, Research and Forecasting model coupled with Chemistry (WRF-Chem), with the aim of improving model prediction of trace atmospheric gas-phase chemical and aerosol composition, and of interactions between air quality and weather. A reduced form of the Common Reactive Intermediates gas-phase chemical mechanism (CRIv2-R5) has been added, using the Kinetic Pre-Processor (KPP) interface, to enable more explicit simulation of VOC degradation. N2O5 heterogeneous chemistry has been added to the existing sectional MOSAIC aerosol module, and coupled to both the CRIv2-R5 and existing CBM-Z gas-phase schemes. Modifications have also been made to the sea-spray aerosol emission representation, allowing the inclusion of primary organic material in sea-spray aerosol. We have worked on the European domain, with a particular focus on making the model suitable for the study of nighttime chemistry and oxidation by the nitrate radical in the UK atmosphere. Driven by appropriate emissions, wind fields and chemical boundary conditions, implementation of the different developments are illustrated, using a modified version of WRF-Chem 3.4.1, in order to demonstrate the impact that these changes have in the Northwest European domain. These developments are publicly available in WRF-Chem from version 3.5.1 onwards.

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