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| Titel |
Modelled radiative effects of sea spray aerosol using a source function encapsulating wave state |
| VerfasserIn |
Antti-Ilari Partanen, Eimear M. Dunne, Tommi Bergman, Anton Laakso, Harri Kokkola, Jurgita Ovadnevaite, Larisa Sogacheva, Dominique Baisnee, Jean Sciare, Astrid Manders, Colin O'Dowd, Gerrit de Leeuw, Hannele Korhonen |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250096834
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| Publikation (Nr.) |
 EGU/EGU2014-12358.pdf |
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| Zusammenfassung |
| Sea spray aerosol particles have significant effects on global climate by scattering solar
radiation (direct effect) and modifying cloud properties (indirect effect). Sea spray consists
mainly of sea salt, but in biologically active regions, major fraction of sea spray
may come in the form of primary marine organic matter (PMOM). Traditionally,
sea spray flux has been parameterized in global models in terms of wind speed,
and organic fraction of sea spray in terms of chlorophyll-a concentration. In this
study, we have incorporated recently developed parameterizations for the sea spray
aerosol source flux into the global aerosol-climate model ECHAM-HAMMOZ. The
parameterizations encapsulate the wave state via Reynolds number, and predict the
organic fraction of the sea spray aerosol source flux. The model was then used to
investigate the direct and indirect effects of sea spray aerosol particles. We compared
simulated sea spray concentrations with in-situ measurements from Mace Head (North
Atlantic), Point Reyes (North Pacific), and Amsterdam Island (Southern Indian
Ocean). Aerosol optical depth (AOD) was compared with satellite measurements from
PARASOL.
Modelled annual mean global emissions of sea salt and PMOM were 805 Tg yr-1
(uncertainty range of 378-1233 Tg yr-1) and 1.1 Tg yr-1 (0.5-1.8 Tg yr-1), respectively.
Sea salt emissions were considerably lower than the majority of previous estimates, but
PMOM was in the range of previous studies.
The model captured sea salt concentrations fairly well in the smaller size ranges at Mace
Head (annual normalized mean bias of -13% for particles with vacuum aerodynamic
diameter Dva |
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