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Abstract The formation of ice in clouds can strongly impact cloud properties and precipitation processes during storms, including atmospheric rivers. Sea spray aerosol (SSA) particles are relatively inefficient as ice nucleating particles (INPs) compared to mineral dust. However, due to the vast coverage of the Earth's surface by the oceans, a number of recent studies have focused on identifying sources of marine INPs, particularly in regions lacking a strong influence from dust. This study describes the integration, validation, and application of a system coupling a continuous flow diffusion chamber with a single particle mass spectrometer using a pumped counterflow virtual impactor to remove nonnucleated particles and selectively measure the composition of INPs with a detection efficiency of 3.10×10−4. In situ measurements of immersion freezing INP composition were made at a coastal site in California using the integrated system. Mineral dust particles were the most abundant ice crystal residual type during the sampling period and found to be ice active despite having undergone atmospheric processing. SSA were more abundant in ambient measurements but represented only a minor fraction of the ice crystal residual population at −31 °C. Notably, the SSA particles that activated were enriched with organic nitrogen species that were likely transferred from the ocean. Calculations of ice nucleation active site densities were within good agreement with previous studies of mineral dust and SSA.
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Atmospheric oxidation impact on sea spray produced ice nucleating particles
Ice nucleating particles (INPs) in sea spray aerosol (SSA) are important for ice formation in clouds over oceans. We found that SSA INP concentrations during a phytoplankton bloom were degraded with exposure to 3 to 8 days of atmospheric oxidation.
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- Award ID(s):
- 1801971
- PAR ID:
- 10555770
- Publisher / Repository:
- The Royal Society of Chemistry
- Date Published:
- Journal Name:
- Environmental Science: Atmospheres
- Volume:
- 3
- Issue:
- 10
- ISSN:
- 2634-3606
- Page Range / eLocation ID:
- 1513 to 1532
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D3EA00060E
