AIR POLLUTION – MONITORING MODELLING AND HEALTH

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Air Pollution – Monitoring, Modelling and Health
Fig. 9. Surface winds at 10m on 18 January 1993 at 00Z.
The hourly concentrations of PM 10 were examined by several researchers. As an example,
Karaca et al. (2005) interpreted the analyses for monthly average variations of PM 10
concentrations in Istanbul. The numerical results of the study indicate that cyclonic behavior
of the time series of PM 10 concentrations occurs in winter and summer times with the effect
of prevailing meteorological conditions. According to Kindap et al. (2006) Istanbul had
hourly PM 10 levels observed from monitoring sites that were in excess of 300µg/m 3 at
several locations in the beginning of 2000s. Attributing to predominantly westerly winds at
this period it is investigated that long-range transport is effective on elevating PM levels in
Istanbul. Following the 2000s, air quality levels for Istanbul present different characteristics
based on the changing of emission sources in the city. Fig. 10 presents the temporal variation
of the annual average concentrations of some critical pollutants following fuel switching
period in the city. In this figure, the hourly PM 10 , SO 2 and NO x , concentrations reported over
the five year period (1 January 2005 through 31 December 2010).As seen in the figure sulfur
dioxide concentrations in the city remained below the air quality standards whereas PM 10
and NO 2 concentrations exceeded the air quality standards.