Atmospheric black carbon in Helsinki
Atmospheric fine particle black carbon (BC) was measured close to downtown of Helsinki, during November 1996–June 1997. The average BC concentrations were 1.5 μg m −3 for working days, 1.2 μg m −3 for Saturdays, and about 1 μg m −3 for Sundays and public holidays. The overall average BC concentratio...
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Published in | Atmospheric environment (1994) Vol. 34; no. 9; pp. 1497 - 1506 |
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Main Authors | , , , , , |
Format | Journal Article |
Language | English |
Published |
Oxford
Elsevier Ltd
2000
Elsevier Science |
Subjects | |
Online Access | Get full text |
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Summary: | Atmospheric fine particle black carbon (BC) was measured close to downtown of Helsinki, during November 1996–June 1997. The average BC concentrations were 1.5
μg
m
−3 for working days, 1.2
μg
m
−3 for Saturdays, and about 1
μg
m
−3 for Sundays and public holidays. The overall average BC concentration was equal to 1.38
μg
m
−3 and its average contribution to fine particle mass equal to 19%. On working days BC concentrations showed a clear diurnal variation with the highest hourly average values occurring during the morning (2.7
μg
m
−3) and evening (1.9
μg
m
−3) rush hours. Contribution of the long-range transport to the BC was estimated to be on average about 0.4
μg
m
−3, which is believed to represent the average regional background over southern Finland. However, this transport was very different from different geographical regions: from the densely populated areas of East- and Central-Europe it was about 0.8
μg
m
−3, while in northerly and northwesterly air masses it was only about 0.15
μg
m
−3. Local traffic was by far the most important local BC source contributing about 63, 54 and 44% on working days, Saturdays and Sundays, respectively. Other local sources were largely masked by the traffic and their contribution was estimated roughly to be of the order of 10%. The rest of BC was attributed to long-range transport. |
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Bibliography: | ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 |
ISSN: | 1352-2310 1873-2844 |
DOI: | 10.1016/S1352-2310(99)00344-1 |