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| Titel |
Aerosol ageing in an urban plume – implication for climate |
| VerfasserIn |
P. Roldin, E. Swietlicki, A. Maßling, A. Kristensson, J. Löndahl, A. Eriksson, J. Pagels, S. Gustafsson |
| 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 ; 11, no. 12 ; Nr. 11, no. 12 (2011-06-22), S.5897-5915 |
| Datensatznummer |
250009864
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| Publikation (Nr.) |
 copernicus.org/acp-11-5897-2011.pdf |
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| Zusammenfassung |
| The climate effects downwind of an urban area resulting from gaseous and
particulate emissions within the city are as yet inadequately quantified.
The aim of this work was to estimate these effects for Malmö city in
southern Sweden (population 280 000). The chemical and physical particle
properties were simulated with a model for Aerosol Dynamics, gas phase
CHEMistry and radiative transfer calculations (ADCHEM) following the
trajectory movement from upwind of Malmö, through the urban background
environment and finally tens and hundreds of kilometers downwind of
Malmö. The model results were evaluated using measurements of the
particle number size distribution and chemical composition. The total
particle number concentration 50 km (~ 3 h) downwind, in the center
of the Malmö plume, is about 3700 cm−3 of which the Malmö
contribution is roughly 30%. Condensation of nitric acid, ammonium and to
a smaller extent oxidized organic compounds formed from the emissions in
Malmö increases the secondary aerosol formation with a maximum of
0.7–0.8 μg m−3 6 to 18 h downwind of Malmö. The secondary
mass contribution dominates over the primary soot contribution from
Malmö already 3 to 4 h downwind of the emission sources and
contributes to an enhanced total surface direct or indirect aerosol
shortwave radiative forcing in the center of the urban plume ranging from
−0.3 to −3.3 W m−2 depending on the distance from Malmö, and the
specific cloud properties. |
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