English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The extent to which water uptake influences the light scattering ability ofmarine sea spray aerosol (SSA) particles depends critically on SSA chemicalcomposition. The organic fraction of SSA can increase during phytoplanktonblooms, decreasing the salt content and therefore the hygroscopicity of theparticles. In this study, subsaturated hygroscopic growth factors at 85 %relative humidity (GF(85 %)) of predominately submicron SSA particleswere quantified during two induced phytoplankton blooms in marine aerosolreference tanks (MARTs). One MART was illuminated with fluorescent lights andthe other was illuminated with sunlight, referred to as the "indoor" and"outdoor" MARTs, respectively. Optically weighted GF(85 %) values forSSA particles were derived from measurements of light scattering and particlesize distributions. The mean optically weighted SSA diameters were 530 and570 nm for the indoor and outdoor MARTs, respectively. The GF(85 %)measurements were made concurrently with online particle compositionmeasurements, including bulk composition (using an Aerodyne high-resolutionaerosol mass spectrometer) and single particle (using an aerosoltime-of-flight mass spectrometer) measurement, and a variety ofwater-composition measurements. During both microcosm experiments, theobserved optically weighted GF(85 %) values were depressed substantiallyrelative to pure inorganic sea salt by 5 to 15 %. There was also a timelag between GF(85 %) depression and the peak chlorophyll a (Chl a)concentrations by either 1 (indoor MART) or 3-to-6 (outdoorMART) days. The fraction of organic matter in the SSA particles generallyincreased after the Chl a peaked, also with a time lag, and ranged fromabout 0.25 to 0.5 by volume. The observed depression in the GF(85 %)values (relative to pure sea salt) is consistent with the large observedvolume fractions of non-refractory organic matter (NR-OM) comprising the SSA.The GF(85 %) values exhibited a reasonable negative correlation with theSSA NR-OM volume fractions after the peak of the blooms (i.e., Chl amaxima); i.e., the GF(85 %) values generally decreased when the NR-OMvolume fractions increased. The GF(85 %) vs. NR-OM volume fractionrelationship was interpreted using the Zdanovskii–Stokes–Robinson (ZSR)mixing rule and used to estimate the GF(85 %) of the organic matter inthe nascent SSA. The estimated pure NR-OM GF(85 %) values were1.16 ± 0.09 and 1.23 ± 0.10 for the indoor and outdoor MARTS,respectively. These measurements demonstrate a clear relationship between SSAparticle composition and the sensitivity of light scattering to variations inrelative humidity. The implications of these observations to the directclimate effects of SSA particles are discussed

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