关键词: 遥感, 气溶胶成分, APEC会议, OPAC模型

Abstract:

Variation of aerosol components impact greatly on air pollution and climate change, and remote sensing is able to detect aerosol composition properties while maintaining the natural states of ambient aerosol. Based on microphysical and optical properties of black carbon (BC), water soluble component (WASO), insoluble component (INSO) and mineral dust (DUST) provided by optical properties of aerosols and clouds (OPAC) model, mass concentration of the four components were retrieved and their contributions to total aerosol optical depth were calculated by using aerosol properties acquired from ground-based sun-sky radiometer measurements during APEC Forum days in Beijing in 2014. Results show that the average AOD (440 nm) on APEC Forum days (0.25) is much lower than that of pre-Forum days (0.72) and post-Forum days (0.57), and WASO dominantly contributes to the total aerosol optical depth. Mass density of BC, WASO, INSO, DUST is respectively 0.8 μg/m3、139.6 μg/m3、184.2 μg/m3、194.3 μg/m3 on pre-forum days, 1.1 μg/m3、56.4 μg/m3、40.3 μg/m3、7.8 μg/m3 on APEC Forum days, and 1.0 μg/m3、126.6 μg/m3、157.1 μg/m3、30.9 μg/m3 on post-Forum days. BC mass density doesn’t change much during APEC Forum, while the numeric numbers of mass densities of WASO, INSO, and DUST in APEC Forum days are much lower compared to those of pre-forum days and post-forum days. This illustrates clearly that the control measures for improving air quality undertaken by the government have been taking effect during APEC Forum days. In-situ measurements of BC concentration were used by aethalometer to verify the BC retrieval and find that the retrieved BC mass concentration agrees well with measured content with the correlation coefficient R2 of 0.68.

Key words: remote sensing, aerosol components, APEC, optical properties of aerosols and clouds model