Size-Dependent Morphology, Composition, Phase State, and Water Uptake of Nascent Submicrometer Sea Spray Aerosols during a Phytoplankton Bloom

Abstract. In situ measurements of aerosol water uptake and activation of aerosols into cloud droplets provide information on how aerosols influence the microphysical properties of clouds. Here we present a computational scheme that can be used in connection with such measurements to assess the influence of the particle hygroscopicity and mixing state (in terms of the water uptake) on the cloud nucleating ability of particles. Additionally, it provides an estimate for the peak supersaturation of water vapour reached during the formation of the observed cloud(s). The method was applied in interpreting results of a measurement campaign that focused on aerosol-cloud interactions taking place at a subarctic background site located in Northern Finland (second Pallas Cloud Experiment, 2nd PaCE). A set of case studies was conducted, and the observed activation behavior could be successfully explained by a maximum supersaturation that varied between 0.18 and 0.26% depending on the case. In these cases, the diameter corresponding to the activated fraction of 50% was in the range of 110–140 nm, and the particles were only moderately water soluble with hygroscopic growth factors varying between 1.1 and 1.4. The conducted analysis showed that the activated fractions and the total number of particles acting as CCN are expected to be highly sensitive to the particle hygroscopic growth properties. For example, the latter quantity varied over a factor between 1.8 and 3.1, depending on the case, when the mean hygroscopic growth factors were varied by 10%. Another important conclusion is that size-dependent activation profiles carries information on the mixing state of particles.

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Size-Dependent Changes in Sea Spray Aerosol Composition and Properties with Different Seawater Conditions

Environmental Science & Technology ◽

10.1021/es400416g ◽

2013 ◽

Vol 47 (11) ◽

pp. 5603-5612 ◽

Cited By ~ 120

Author(s):

Andrew P. Ault ◽

Ryan C. Moffet ◽

Jonas Baltrusaitis ◽

Douglas B. Collins ◽

Matthew J. Ruppel ◽

...

Keyword(s):

Sea Spray ◽

Aerosol Composition ◽

Size Dependent ◽

Sea Spray Aerosol

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review of Sea spray aerosol organic enrichment, water uptake and surface tension effects

10.5194/acp-2019-797-rc2 ◽

2019 ◽

Author(s):

Christopher Oxford

Keyword(s):

Surface Tension ◽

Water Uptake ◽

Organic Enrichment ◽

Sea Spray ◽

Sea Spray Aerosol

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Фазовая диаграмма состояния и межфазные характеристики в бинарной наносистеме

Физика твердого тела ◽

10.21883/ftt.2018.01.45307.099 ◽

2018 ◽

Vol 60 (1) ◽

pp. 180

Author(s):

М.А. Шебзухова ◽

А.А. Шебзухов

Keyword(s):

Interfacial Tension ◽

Size Effects ◽

Interfacial Layer ◽

Phase State ◽

Calculated Data ◽

Size Composition ◽

Size Dependent ◽

State Diagrams ◽

Monodispersed Particles ◽

The Matrix

AbstractThe size effects on the composition of coexisting phases, the interfacial layer between them, and the interfacial tension in a binary system composed of a matrix and the monodispersed particles of arbitrary (including nanoscale) size are described in the context of a Gibbs method for dispersed systems. Obtaining the relevant relationships has allowed plotting the size-dependent phase state diagrams for a Cr–Ti system with a point of equal concentrations with a minimum. The coefficients of size composition of the nanoparticles and the matrix, as well as those of interfacial tension under the isobaric and isothermal conditions, are calculated at different degree of dispersion. The calculated data coincide with the experimental ones.

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Factors driving the seasonal and hourly variability of sea-spray aerosol number in the North Atlantic

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1907574116 ◽

2019 ◽

Vol 116 (41) ◽

pp. 20309-20314 ◽

Cited By ~ 6

Author(s):

Georges Saliba ◽

Chia-Li Chen ◽

Savannah Lewis ◽

Lynn M. Russell ◽

Laura-Helena Rivellini ◽

...

Keyword(s):

Wind Speed ◽

North Atlantic ◽

Climate Models ◽

Marine Boundary Layer ◽

Phytoplankton Bloom ◽

Cloud Condensation Nuclei ◽

Sea Spray ◽

Wind Speeds ◽

The North ◽

Sea Spray Aerosol

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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Linking hygroscopicity and the surface microstructure of model inorganic salts, simple and complex carbohydrates, and authentic sea spray aerosol particles

Physical Chemistry Chemical Physics ◽

10.1039/c7cp04051b ◽

2017 ◽

Vol 19 (31) ◽

pp. 21101-21111 ◽

Cited By ~ 29

Author(s):

Armando D. Estillore ◽

Holly S. Morris ◽

Victor W. Or ◽

Hansol D. Lee ◽

Michael R. Alves ◽

...

Keyword(s):

Water Uptake ◽

Aerosol Particles ◽

Inorganic Salts ◽

Surface Microstructure ◽

Sea Spray ◽

Sea Spray Aerosol ◽

Complex Carbohydrates

Sea spray aerosol (SSA) particles are mixtures of organics and salts that show diversity in their morphologies and water uptake properties.

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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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Aerosol optical hygroscopicity measurements during the 2010 CARES campaign

Atmospheric Chemistry and Physics ◽

10.5194/acp-15-4045-2015 ◽

2015 ◽

Vol 15 (8) ◽

pp. 4045-4061 ◽

Cited By ~ 12

Author(s):

D. B. Atkinson ◽

J. G. Radney ◽

J. Lum ◽

K. R. Kolesar ◽

D. J. Cziczo ◽

...

Keyword(s):

Water Uptake ◽

Light Extinction ◽

Carbonaceous Aerosols ◽

Hygroscopic Growth ◽

Particle Size Distributions ◽

Range Analysis ◽

Size Dependent ◽

Atmospheric Processing ◽

Influence Of Water

Abstract. Measurements of the effect of water uptake on particulate light extinction or scattering made at two locations during the 2010 Carbonaceous Aerosols and Radiative Effects Study (CARES) study around Sacramento, CA are reported. The observed influence of water uptake, characterized through the dimensionless optical hygroscopicity parameter γ, is compared with calculations constrained by observed particle size distributions and size-dependent particle composition. A closure assessment has been carried out that allowed for determination of the average hygroscopic growth factors (GFs) at 85% relative humidity and the dimensionless hygroscopicity parameter κ for oxygenated organic aerosol (OA) and for supermicron particles (defined here as particles with aerodynamic diameters between 1 and 2.5 microns), yielding κ = 0.1–0.15 and 0.9–1.0, respectively. The derived range of oxygenated OA κ values are in line with previous observations. The relatively large values for supermicron particles is consistent with substantial contributions of sea-salt-containing particles in this size range. Analysis of time-dependent variations in the supermicron particle hygroscopicity suggest that atmospheric processing, specifically chloride displacement by nitrate and the accumulation of secondary organics on supermicron particles, can lead to substantial depression of the observed GF.

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