Paper Title
Air Quality Dispersion Modeling in the City Of Istanbul by Calmet/Calpuff Modeling System

Abstract
The CALMET/CALPUFF modeling system was used to calculate the dispersion of pollutants from anthropogenic sources in Istanbul, Turkey. The study area was selected as 170 km x 85 km to cover the Istanbul metropolitan area. The emission sources were broadly categorized as point, line and area sources, covering industrial, vehicular and residential sources respectively. Five major pollutants consisting of particulate matter (PM10), sulfur dioxide (SO2), carbon monoxide (CO), non-methane volatile organic compounds (NMVOCs) and nitrogen oxides (NOX) emitted through these sources were identified. Meteorological data was obtained from 25 meteorological stations operated by Turkish State Meteorological Service and Istanbul Metropolitan Municipality which are located around the center of the city of Istanbul. The data for the parameters of wind speed, wind direction, temperature, pressure, humidity, precipitation and cloudiness were taken from all stations as hourly basis for the year 2007.CALPUFF model performance was also tested by comparing the predicted pollutant concentrations with those measured at ten ambient air quality stations. Mainly two methods were used: root of the mean square error (RMSE) and an index of agreement (d). Index Terms- Air Quality Modeling, Dispersion, CALPUFF, Istanbul.