|
Titel |
Significant variations of trace gas composition and aerosol properties at Mt. Cimone during air mass transport from North Africa – contributions from wildfire emissions and mineral dust |
VerfasserIn |
P. Cristofanelli, A. Marinoni, J. Arduini, U. Bonafè, F. Calzolari, T. Colombo, S. Decesari, R. Duchi, M. C. Facchini, F. Fierli, E. Finessi, M. Maione, M. Chiari, G. Calzolai, P. Messina, E. Orlandi, F. Roccato, P. Bonasoni |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
1680-7316
|
Digitales Dokument |
URL |
Erschienen |
In: Atmospheric Chemistry and Physics ; 9, no. 14 ; Nr. 9, no. 14 (2009-07-17), S.4603-4619 |
Datensatznummer |
250007505
|
Publikation (Nr.) |
copernicus.org/acp-9-4603-2009.pdf |
|
|
|
Zusammenfassung |
High levels of trace gas (O3 and CO) and aerosol (BC, fine and coarse
particle volumes), as well as high scattering coefficient
(σp) values, were recorded at the regional GAW-WMO station of
Mt. Cimone (CMN, 2165 m a.s.l., Italy) during the period 26–30 August
2007. Analysis of air-mass circulation, aerosol chemical characterization
and trace gas and aerosol enhancement ratios (ERs), showed that high O3
and aerosol levels were likely linked to (i) the transport of anthropogenic
pollution from northern Italy, and (ii) the advection of air masses rich in
mineral dust and biomass burning (BB) products from North Africa. In
particular, during the advection of air masses from North Africa, the CO and
aerosol levels (CO: 175 ppbv, BC: 1015 ng/m3, fine particle volume:
3.00 μm3 cm−3, σp: 84.5 Mm−1) were even
higher than during the pollution event (CO: 138 ppbv, BC: 733 ng/m3,
fine particles volume: 1.58 μm3 cm−3, σp: 44.9 Mm). Moreover, despite the presence of mineral dust able to affect
significantly the O3 concentration, the analysis of ERs showed that the
BB event represented an efficient source of fine aerosol particles (e.g.
BC), but also of the O3 recorded at CMN. In particular, the calculated
O3/CO ERs (0.10–0.17 ppbv/ppbv) were in the range of values found in
literature for relatively aged (2–4 days) BB plumes and suggested
significant photochemical O3 production during the air-mass transport.
For fine particles and σp, the calculated ERs was higher in the
BB plumes than during the anthropogenic pollution events, stressing the
importance of the identified BB event as a source of atmospheric aerosol
able to affect the atmospheric radiation budget. These results suggest that
episodes of mineral dust mobilization and wildfire emissions over North
Africa could significantly influence radiative properties (as deduced from
σp observations at CMN) and air quality over the Mediterranean
basin and northern Italy. |
|
|
Teil von |
|
|
|
|
|
|