Molecular Diversity of Sea Spray Aerosol Particles: Impact of Ocean Biology on Particle Composition and Hygroscopicity

Journal Article · Mon May 01 00:00:00 EDT 2017 · Chem

DOI:https://doi.org/10.1016/j.chempr.2017.03.007· OSTI ID:1358472

Cochran, Richard E.; Laskina, Olga; Trueblood, Jonathan V.; Estillore, Armando D.; Morris, Holly S.; Jayarathne, Thilina; Sultana, Camille M.; Lee, Christopher; Lin, Peng; Laskin, Julia; Laskin, Alexander; Dowling, Jacqueline A.; Qin, Zhen; Cappa, Christopher D.; Bertram, Timothy H.; Tivanski, Alexei V.; Stone, Elizabeth A.; Prather, Kimberly A.; Grassian, Vicki H.

The impact of sea spray aerosol (SSA) on climate depends on the size and chemical composition of individual particles that make-up the total SSA ensemble. While the organic fraction of SSA has been characterized from a bulk perspective, there remains a lack of understanding as to the composition of individual particles within the SSA ensemble. To better understand the molecular components within SSA particles and how SSA composition changes with ocean biology, simultaneous measurements of seawater and SSA were made during a month-long mesocosm experiment performed in an ocean-atmosphere facility. Herein, we deconvolute the composition of freshly emitted SSA devoid of anthropogenic and terrestrial influences by characterizing classes of organic compounds as well as specific molecules within individual SSA particles. Analysis of SSA particles show that the diversity of molecules within the organic fraction varies between two size fractions (submicron and supermicron) with contributions from fatty acids, monosaccharides, polysaccharides and siliceous material. Significant changes in the distribution of these compounds within individual particles are observed to coincide with the rise and fall of phytoplankton and bacterial populations within the seawater. Furthermore, water uptake is impacted as shown by hygroscopicity measurements of model systems composed of representative organic compounds. Thus, the how changes in the hygroscopic growth of SSA evolves with composition can be elucidated. Overall, this study provides an important connection between biological processes that control the composition of seawater and changes in single particle composition which will enhances our ability to predict the impact of SSA on climate.

• Research Organization: Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1358472
• Report Number(s): PNNL-SA-117125; 48375; KP1704020
• Journal Information: Chem, Vol. 2, Issue 5; ISSN 2451-9294
• Country of Publication: United States
• Language: English

Related Subjects

Environmental Molecular Sciences Laboratory