Influence of meteorological factors and emission sources on spatial and temporal variations of PM10 concentrations in Istanbul metropolitan area

Winter weather conditions vs. air quality in Tricity, Poland

“…Such tendency indicates the high pressure weather which contributes to the intensification of heating processes and consequently to the increase in emission of the products of traditional energy sources combustion thereby weakening natural air ventilation. The significant influence of anticyclonic weather on concentration levels of the pollutants was demonstrated by Czarnecka and Nidzgorska-Lencewicz (2011), Drzeniecka-Osiadacz and Netzel (2010a), Unal et al (2011) and Kukkonen et al (2005). The significance of such weather conditions was slightly more marked with respect to particulate matter concentration.…”

“…Cluster analysis is a statistical classification method used to identify homogeneous subgroups in a population and gather them into sets of data basing on their similarity (Gerstengarbe and Werner 1997). As a reliable and relatively simple method of classification, clustering is also used in studies on air quality, with hierarchical clustering being used most commonly (Yonemura et al 2008;Yoo et al 2011;Unal et al 2011). However, in this paper, we use the k-means clustering, which belongs to a group of nonhierarchical cluster analysis methods.…”

“…The results of many studies confirm a positive, ventilation part that wind plays despite lower speed during anticyclonic weather and in a built-up area (Czarnecka and Nidzgorska-Lencewicz 2011;Drzeniecka-Osiadacz and Netzel 2010b;Grivas et al 2004;Ocak and Turalioglu 2010;Pires et al 2008;Zabalza et al 2007). In Istanbul, the average PM10 concentration level calculated for wind speed ≥4.5 m·s −1 was about half that at wind speed below 1 m·s −1 both in the conditions pressure lower as well as higher than 1,018 hPa (Unal et al 2011). Different directional coefficients characterising the relationship between concentration of pollutants and wind speed in the analysed episodes of an increased PM10 concentration in four European cities were obtained by Kukkonen et al (2005) and Vardouulakis and Kassomenos (in Ocak and Turalioglu 2010).…”

“…In the period [2005][2006][2007][2008][2009], mean annual concentration of particulate matter in Istanbul was from 46 to 70 μg·m −3 and the daily standard was exceeded on a regular basis; in some regions, it was exceeded in more than 90 % of days in a year (Unal et al 2011). PM10 measurement series of 1 year duration in Athens showed that the percentage of 24-h admissible value of 50 μg· m −3 was exceeded in 11.5-91.5 % of cases at four sites (Grivas et al 2004).…”

“…The literature on the subject describes winter seasons or episodes of increased or very high concentration of pollution, primarily PM10, which occurred in the conditions of anticyclonic weather marked by freezing weather and constant balance in the lower part of the boundary layer of atmosphere (Czarnecka and Nidzgorska-Lencewicz 2011;Cheng et al 2007;Demuzere et al 2009;DrzenieckaOsiadacz and Netzel 2010b;Grivas et al 2004;Kassomenos et al 2003;Malek et al 2006;Greene et al 1999;Kukkonen et al 2005;Mira-Salama et al 2008;Unal et al 2011;van der Wal and Janssens 2000). In such conditions, the greatest risk of the increase of concentration of pollutants is connected with inversions of temperature often occurring during 24-h periods (Drzeniecka-Osiadacz and Netzel 2010a; İçağa and Sabah 2009;Kuznetsova et al 2008;Silva et al 2007;Wallace et al 2010).…”