Aerosol seasonal variations over urban–industrial regions in Ukraine according to AERONET and POLDER measurements

摘要

The paper presents an investigation of aerosol seasonal variations in severalurban–industrial regions in Ukraine. Our analysis of seasonal variations ofoptical and physical aerosol parameters is based on the sun-photometer2008–2013 data from two urban ground-based AERONET (AErosol RObotic NETwork) sites in Ukraine (Kyiv,Lugansk) as well as on satellite POLDER instrument data for urban–industrialareas in Ukraine. We also analyzed the data from one AERONET site in Belarus(Minsk) in order to compare with the Ukrainian sites. Aerosol amount andoptical depth (AOD) values in the atmosphere columns over the large urbanizedareas like Kyiv and Minsk have maximum values in the spring (April–May) and latesummer (August), whereas minimum values are observed in late autumn. Theresults show that fine-mode particles are most frequently detected during thespring and late summer seasons. The analysis of the seasonal AOD variationsover the urban–industrial areas in the eastern and central parts of Ukraineaccording to both ground-based and POLDER data exhibits the similar traits.The seasonal variation similarity in the regions denotes the resemblance inbasic aerosol sources that are closely related to properties of aerosolparticles. The behavior of basic aerosol parameters in the western part ofUkraine is different from eastern and central regions and shows an earlierappearance of the spring and summer AOD maxima. Spectral single-scatteringalbedo, complex refractive index and size distribution of aerosol particlesin the atmosphere column over Kyiv have different behavior for warm(April–October) and cold seasons. The seasonal features of fine and coarseaerosol particle behavior over the Kyiv site were analyzed. A prevailinginfluence of the fine-mode particles on the optical properties of the aerosollayer over the region has been established. The back-trajectory and clusteranalysis techniques were applied to study the seasonal back trajectories andprevailing directions of the arrived air mass for the Kyiv and Minsk sites.