Analysis and research of absorbing aerosols in Beijing-Tianjin-Hebei region

In the Beijing-Tianjin-Hebei (BTH) urban agglomeration, the atmospheric particulate matter (PM) pollution has become exacerbated year by year. In an attempt to understand the current condition of aerosol particulate pollution in the BTH region, the temporal and spatial distribution, future trend changes, and potential source areas of absorbing aerosols in the BTH region from 2005 to 2019 were analyzed based on Ozone Monitoring Instrument/Aura Near UV Aerosol Optical Depth and Single Scattering Albedo 1-orbit L2 Swath 13 × 24 km V003 (OMAERUV) daily product data; besides, relevant influencing factors were explored in this study. As per the analysis of results, the ultraviolet aerosol index (UVAI) increased by 3.03% in the time series from 2005 to 2019. Spatially, the absorbing aerosol in the North China Plain was always maintained in a high-value area, and the15-year average annual UVAI value has been as high as 0.45. In the monthly time series, a “V” shape started from January. The peak value of seasonal characteristics reached the highest in winter, followed by autumn and spring, and the lowest in summer. The external potential sources in the BTH region are mainly sand and dust sources generated in the northwest, while those of absorbing aerosols are mainly carbon sources in spring, with the lowest external absorbing aerosols in summer. The potential sources of absorbing aerosols in autumn are relatively complicated. The potential sources of absorbing aerosols are mainly sand and dust sources in the north. The time series of absorbing aerosols mainly showed an anti-continuous rise, and 54.23% of absorbing aerosols indicated an upward trend that would occur in the future. The relationship between absorbing aerosols and PM2.5 is mutual conversion. According to the path coefficient, industrial production activities are important sources of atmospheric absorbing aerosols, and precipitation can reduce the content of absorbing aerosols in the atmosphere caused by industrial production.