Long-term temporal analysis of the columnar and surface aerosol relationship with planetary boundary layer height at a southern coastal site of Turkey

摘要

Highlights Long-term relationship between PM10, AOD and PBLH over a coastal region in the southern Turkey was studied. Seasonal variation of the PM10-PBLH relationship over the region was firstly reported. Lower correlations were observed in spring and summer due to the transported aerosols. PM10/AOD ratio by both MODIS and AERONET AODs were used to explore the effect of transported aerosols. Differences were found between low and high polluted seasons.Mersin is industrialized city with 1.8 million people, a dense port, and different industries. The region is under the influence of mineral dust transport originated from the arid and semi-arid regions, mainly in spring and autumn. Planetary boundary layer height (PBLH) is one of major parameters influencing surface air quality. In this study, the relationship between particulate matters having diameter of 10 μm or less (PM10) and PBLH was investigated in an urban coastal site of Turkey. Relationships between PBLH and the ratios of PM10 to Aerosol Optical Depth (AOD) from MODIS and AERONET were also analyzed to account for transported aerosol that is not concentrated in the planetary boundary layer (PBL). PBL is known as the atmospheric boundary layer (ABL) that is the lowest part of the atmosphere and its behavior is directly influenced by its contact with a planetary surface. The PM10, AOD and PBLH showed a seasonal variability with increasing multiyear seasonal mean values of AOD and PBLH from winter to summer while decreasing trend was found for PM10 over the analyzed site. Paired dataset for MODIS overpass and AERONET observational times shared the same seasonal patterns; however, the magnitude of the seasonal variations differed. The relationship of PBLH–PM10 was weak over the site. Positive correlations observed in spring and summer could be characterized by lower PM10 concentrations and transported aerosols over the region. Compared to PBLH–PM10 correlations, the PM10/AOD ratio increased correlations significantly from −0.18 to −0.43 for MODIS overpass time and −0.18 to −0.30 for AERONET observational time. Improvements were also showed seasonal differences.