Akademik Veri Yönetim Sistemi
ATMOSPHERIC ENVIRONMENT, cilt.374, 2026 (SCI-Expanded, Scopus)
This study examined O 3 formation regimes in the Aegean Region (T & uuml;rkiye), a complex environment with diverse pollution sources, including urban, industrial, and biogenic emissions. Satellite-derived Sentinel-5P TROPOMI formaldehyde (HCHO) and nitrogen dioxide (NO 2 ) retrievals were analyzed along with routine ground-level O 3 and NO 2 station measurements to evaluate the spatial and temporal variability of O 3 production, using the formaldehydeto-nitrogen dioxide ratio (FNR) as an indicator of O 3 sensitivity to its precursors. Satellite observations showed high NO 2 ( 4-5 & times; 10 15 molecules cm-2 ) over industrial areas and elevated HCHO ( 1.2 & times; 10 16 molecules cm-2 ) over forested and coastal regions. Region specific FNR ranges were estimated for O 3 formation regimes. Monthly FNR values indicated that NO x -limited regimes increased during summer with consistent NO x -saturated hotspots around polluted regions, while transitional to NO x -saturated regimes were found in Apr and Oct. Significant correlations were found between monthly MDA8O 3 and HCHO (R = 0.50-0.89***) levels in stations. Ozone formation with significantly high levels in the Aegean Region mainly occurred throughout an extended season including Apr and Oct compared to the ozone season (May-Sep). However, there are regions with NO x -saturated regime such as Izmir and Aydin exhibited consistently high NO 2 levels even in summer months. The findings showed significant variation in the region that future ozone control strategies need to be planned according to local conditions.