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Titel |
Ice nucleating particles at a coastal marine boundary layer site: correlations with aerosol type and meteorological conditions |
VerfasserIn |
R. H. Mason, M. Si, J. Li, C. Chou, R. Dickie, D. Toom-Sauntry, C. Pöhlker, J. D. Yakobi-Hancock, L. A. Ladino, K. Jones, W. R. Leaitch, C. L. Schiller, J. P. D. Abbatt, J. A. Huffman, A. K. Bertram |
Medientyp |
Artikel
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Sprache |
Englisch
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ISSN |
1680-7316
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Digitales Dokument |
URL |
Erschienen |
In: Atmospheric Chemistry and Physics ; 15, no. 21 ; Nr. 15, no. 21 (2015-11-10), S.12547-12566 |
Datensatznummer |
250120155
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Publikation (Nr.) |
copernicus.org/acp-15-12547-2015.pdf |
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Zusammenfassung |
Information on what aerosol particle types are the major sources of ice
nucleating particles (INPs) in the atmosphere is needed for climate
predictions. To determine which aerosol particles are the major sources of
immersion-mode INPs at a coastal site in Western Canada, we investigated
correlations between INP number concentrations and both concentrations of
different atmospheric particles and meteorological conditions. We show that
INP number concentrations are strongly correlated with the number
concentrations of fluorescent bioparticles between −15 and −25 °C, and that the size distribution of INPs is most consistent with the size
distribution of fluorescent bioparticles. We conclude that biological
particles were likely the major source of ice nuclei at freezing
temperatures between −15 and −25 °C at this site for the time
period studied. At −30 °C, INP number concentrations are also
well correlated with number concentrations of the total aerosol particles
≥ 0.5 μm, suggesting that non-biological particles may have an
important contribution to the population of INPs active at this temperature.
As we found that black carbon particles were unlikely to be a major source
of ice nuclei during this study, these non-biological INPs may include
mineral dust. Furthermore, correlations involving chemical tracers of marine
aerosols and marine biological activity, sodium and methanesulfonic acid,
indicate that the majority of INPs measured at the coastal site likely
originated from terrestrial rather than marine sources. Finally, six
existing empirical parameterizations of ice nucleation were tested to
determine if they accurately predict the measured INP number concentrations.
We found that none of the parameterizations selected are capable of
predicting INP number concentrations with high accuracy over the entire
temperature range investigated. This finding illustrates that additional
measurements are needed to improve parameterizations of INPs and their
subsequent climatic impacts. |
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