Evaluation of NOx emissions for Turkey using satellite and ground-based observations

Abstract

Abstract The aim of this study was to evaluate NO x emissions from available inventories using satellite NO 2 retrievals for Turkey. NO x emissions from two available inventories (EMEP and TNO) were compared with each other, differences and similarities were determined. NO x emission inventories were also compared with OMI NO 2 satellite retrievals. Correlation coefficients (R 2 ) between parameters and emissions were found in the range of 0.29–0.69 for selected high populated cities. OMI NO 2 satellite retrievals overpass NO 2 ground observation stations were also processed and the correlation between these observations for selected cities were found highest in summer and lowest in fall and winter. According to the comparison for individual cities, good correlations were observed for Ankara (R 2 = 0.62), Izmir (R 2 = 0.59) and Istanbul (R 2 = 0.90). Weekly profiles and weekend/weekday ratios for ground-based and OMI NO 2 observations were calculated and weekly profiles used for EMEP were also compared with observed weekly profiles. Findings showed that OMI is able to detect polluted regions in Turkey, but there are discrepancies between OMI and ground-based NO 2 observations. Results also indicated issues on NO x emissions of large scale power plants in EMEP emission inventory for Turkey.