Seasonal variability of PM concentration in Tashkent

Abstract

Several hundred cities of the world, have announced goals to become "smart" cities that include environmental sustainability, health, climate-resiliency and livability. Tashkent is capital city of Uzbekistan can count a candidate to the list of "smart" environmentally-sustainable, healthy and livable cities. To investigate the ambient mass concentration, size-distribution and seasonal variability of atmospheric particulate matter (PM), a long-term monitoring campaign was undertaken at an urban background site of Tashkent city during 3 year period (December 1, 2011-November 30, 2014). Goal of the current paper is to analyze the seasonal variations of PM10 and PM2.5 concentration in the ambient air of the city. Monitoring of PM was carried out according to requirements of European standards and during monitoring, a low-volume PNS 16T-3.1 sampler, as well as quartz and fiberglass filters with a diameter of 47 mm, were used. Diurnal concentration of particles in atmospheric air was determined by the gravimetric method. The PM concentration levels varied greatly, with higher mean mass concentrations during the heating season. For whole monitoring period average concentration of PM2.5=29.3±13.5 μg/m3 and PM10=55.4±21.7 μg/m3 and that is under interim target values but higher than WHO recommended value (respectively equal to 10 μg/m3 and 20 μg/m3). Wintertime observed high concentration of PM compared to summer and spring (average PM2.5=42.0 μg/m3 and PM10=63.7 μg/m3). Springtime observed lower concentration of PM (average PM2.5=22.3 μg/m3 and PM10=45.9 μg/m3). Highest concentration of PM was observed in February (average PM2.5=45.0 μg/m3 and PM10=67.8 μg/m3) and lowest in June (average PM2.5=19.6 μg/m3 and PM10=41.7 μg/m3).