A comprehensive overview of PM10 levels in İstanbul: annual and seasonal spatio-temporal variations and the long-distance transport

This study provides a comprehensive overview of the particulate matter with aerodynamic diameters 10 µm (PM10) levels in the megacity Istanbul. PM10 concentrations of ten ambient air quality monitoring stations in Istanbul were studied for the period of 2007-2015. The study focuses on: (i) similarities and differences among urban areas, (ii) on spatial and temporal variations of PM10, (iii) emission sources within Istanbul, (iv) long-distance PM10 transport. PM10 concentrations in Istanbul show significant variations across the megacity, with high PM10 levels at heavy traffic points and industrial zones. Results indicate that the number of exceedences allowed by the EU standards is violated daily and annually at all monitoring sites which indicate serious air quality problem in Istanbul. The seasonal variation is characterized by high concentrations in the winter, and autumn, and low concentrations in the summer. Studies on high PM10 episodes shed light on key atmospheric driving mechanisms which transport air parcels from the Atlantic, Europe and North Africa.