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The rapidly warming Arctic has transitioned to thinner sea ice which fractures, producing leads. Few studies have investigated Arctic sea spray aerosol (SSA) produced from open ocean, leads, and melt ponds, which vary in salinity and organic and microbial community composition. A marine aerosol reference tank was deployed aboard an icebreaker to the Arctic Ocean during August–September 2018 to study SSA generated from locally collected surface waters. Aerosol generation experiments were carried out using water collected from the marginal ice zone, a human-made hole in sea ice near the North Pole, and both lead and melt pond water during an ice floe drift period. Salinity, chlorophyll a, organic carbon, nitrogen, and microbial community composition were measured. Eukaryotic plankton and bacterial abundance were elevated in experimental water from the marginal ice zone, but the relative contributions from major eukaryotic taxonomic groups varied little across the experiments. The chemical composition of individual SSA particles was analyzed using Raman microspectroscopy and computer-controlled scanning electron microscopy with energy-dispersive X-ray spectroscopy. Individual sea salt aerosol, primary organic aerosol, and mineral dust particles were observed. Sea salt aerosol constituted 44–95% of individual submicrometer and 68–100% of supermicrometer particles, by number, generated during each experiment. Carbon was detected in 85%, by number, of the individual sea salt particles, with visible organic coatings. Carbohydrates were detected in 72% of particles, by number, with smaller contributions from long-chain fatty acids (13%) and siliceous material (15%). SSA generated from melt pond water contained only long-chain fatty acids and siliceous material. Quantification of the ice-nucleating activity showed that locally produced SSA may define the High Arctic background ice-nucleating particle population, but cannot account for the peak atmospheric concentrations observed. As the Arctic warms, the increasing SSA emissions have a complex dependence on changing biological and physical processes.
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High Arctic Ocean seawater and aerosol data, August-September 2018
The Arctic is rapidly warming and has transitioned to thinner sea ice which fractures, producing leads. Sea ice loss is expected to be increasing sea spray aerosol production in the High Arctic. Few studies have investigated Arctic sea spray aerosol (SSA) produced from open ocean, leads, and melt ponds, characterized by varied salinity, microbial community, and organic composition. The concentrations, size distributions, single-particle composition, and ice-nucleating activity of the SSA experimentally-generated were measured and compared to the chemical and biological properties of the surface waters. A marine aerosol reference tank (MART) was deployed aboard the Swedish Icebreaker Oden to the high Arctic Ocean during August – September 2018 to study SSA generated from locally-collected surface water. Surface water salinity, chlorophyll-a, organic carbon, nitrogen, and microbial community composition (18s and 16s DNA-derived, flow cytometry of nano- and picoplankton) data are submitted. Experimental aerosol data submitted include type, size, mole ratio, Raman spectra, Raman type, and ice nucleating particles. High resolution Fourier Transform Ion Cyclotron Resonance mass spectrometry (FTICR-MS) data for surface water and experimentally-generated aerosol dissolved organic matter are included .
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- PAR ID:
- 10488952
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- Arctic Ocean aerosol air-sea exchange biogeochemical processes sea ice pack ice leads dissolved organic matter
- Format(s):
- Medium: X
- Location:
- High Arctic Ocean
- Sponsoring Org:
- National Science Foundation
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