 |
| Titel |
Long-term measurement of aerosol chemical composition in Athens, Greece. |
| VerfasserIn |
Despina Paraskevopoulou, Eleni Liakakou, Christina Theodosi, Evangelos Gerasopoulos, Nikolaos Mihalopoulos |
| Konferenz |
EGU General Assembly 2014
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250096992
|
| Publikation (Nr.) |
 EGU/EGU2014-12528.pdf |
|
|
|
|
|
| Zusammenfassung |
| The collection of our samples was conducted for a period of five years (2008 – 2013) in
Athens, Greece. The site is situated at the premises of the National Observatory of Athens on
Penteli Hill, northeast Athens suburbs, and is considered an urban background station. The
aim of our study was a first long-term estimation of the chemical mass closure of aerosol. For
the purposes of the study, we applied three filter samplers during the sampling period:
two Partisol FRM Model 2000 air samplers (one of them collecting PM10 and the
other PM2.5 fractions of aerosol) and one Dichotomous Partisol auto-sampler (with
PM2.5 and PM2.5-10 inlet). Aerosols were collected on Whatman QM-A quartz
fiber filters and the mass of the collected samples was estimated by weighing the
pre-combusted filters before and after sampling, under controlled conditions, using a
microbalance. All quartz filters were analysed for organic (OC) and elemental carbon
(EC) by a thermal – optical transmission technique. The concentration of water
soluble organic carbon (WSOC) was defined for each filter using a total organic
carbon analyzer, while the content in main water soluble ions (Cl-, Br-, NO-3,
SO4-2, PO4-3, C2O4-2, NH4+, K+, Na+, Mg+2, Ca+2) was determined by ion
chromatography. Additionally the filters were analyzed for trace metals by inductively
coupled plasma optical emission spectrometry (ICP-OES). Aerosol chemical mass
closure calculations were conducted for the PM2.5 fraction. The area of Athens is
characterized by aged aerosol that can originate from the marine boundary layer,
the European mainland and occasionally from North African desert areas. The
contribution of dust and particulate organic matter on PM levels was estimated
taking into consideration the location of the sampling site, while identification and
evaluation of sources was performed. Additionally, non-sea salt concentrations of the
main ions were estimated to complete the chemical closure in the extended area.
According to this first analysis of the aforementioned acquired data, the dominant
components of fine particulate matter were carbonaceous aerosol, dust and sulfate
anions. The average mass concentration of PM2.5 was 20μg/m3 for the whole studied
period while, about 23%, 20% and 15% of the total mass is due to POM, dust and
nssSO4-2, respectively. As a result of the mass closure exercise the measured PM2.5
fraction, collected in the studied site, was feasible to be reconstructed to a large extent. |
|
|
|
|
|
|