Chemistry Reference
In-Depth Information
Greater Athens Area and 8 stations in the Greater Thessaloniki Area covering
traffic sites, urban and suburban areas and also industrial areas. In addition other
monitoring sites in smaller urban centres (Patras, Volos, Heraklio) have been set.
In Cyprus air quality is accessed through a network of nine monitoring stations
covering urban, industrial and rural sites.
Except from these national network other remote monitoring stations have been
established by EMEP (European Monitoring and Evaluation Programme) at the
sites of Finokalia (Grete island, Greece), Aliartos (Central Greece) and Ayia
Marina (Cyprus), while a monitoring station of the GAW (Global Atmosphere
Watch) programme of WHO (World Health Organization) has been established at
Athens suburban area (DEM, Agia Paraskevi). These stations provide continuous
measurements of gaseous pollutants (O
3
, CO, NO
x
) and also measurements of
particle properties (optical properties, chemical composition, mass and mass size
distribution).
The monitoring network in EMB compared to those established in Central and
North Europe or even with the Western Mediterranean Basin (e.g.: Spain) is rather
insufficient. Particularly there is a lack of data on continuous or long-term moni-
toring of the chemical composition of particulate matter [
12
]. For some substances
(e.g. carbonaceous aerosol), the variability is expected to be much larger than can
be resolved by integrating the available measurements and the research studies need
to be supported by assessment of the local scale variability. In order to understand
the temporal evolution (trends) there is also a particular need for aerosol
measurements at additional sites with little influence from local and regional
emission sources.
4 Particulate Matter in the Eastern Mediterranean Basin
A number of studies (e.g.: [
13
-
22
]) have investigated PM concentration levels and
their temporal trends in urban sites of Athens. Similarly in the city of Thessaloniki,
PM pollution has been the subject of many studies since the early 1990s (e.g.,
[
23
-
26
]). All these studies have reached the conclusion that urban centres in Greece
(Athens and Thessaloniki) exhibit high PM concentrations, compared to other Euro-
pean and US cities of the same size. In both cities, all urban stations exceeded the EU
annual and 24-h limits several times during the last decade. The long-termmonitoring
of PM concentrations in the Athens area [
14
,
16
,
27
,
28
] registered the occurrence of a
significant number of PM
10
exceedances of the limits established by the EU legisla-
tion and pointed out the need for abatement strategies.
However, the analysis of the PM
10
and PM
2.5
long-term measurements
conducted in an urban background site of Athens reveals that despite the great
variability of the mass concentration values a descending trend exists. Figure
2
summarises the trend analysis of the 24 h PM
10
and PM
2.5
mass concentrations at
the urban background station (Agia Paraskevi) within the GAA for the period
2001-2010. The data were obtained from the public air quality database of
