Satellite Observations of PM2.5 Changes and Driving Factors Based Forecasting Over China 2000–2025
2020
Zhang, Ying | Li, Zhengqiang | Chang, Wenyuan | Zhang, Yuanxun | de Leeuw, Gerrit | Schauer, James J.
In China, atmospheric fine particulate matter (PM₂.₅) pollution is a challenging environmental problem. Systematic PM₂.₅ measurements have started only in 2013, resulting in a lack of historical data which is a key obstacle for the analysis of long-term PM₂.₅ trends and forecasting the evolution over this hot region. Satellite data can provide a new approach to derive historical PM₂.₅ information provided that the column-integrated aerosol properties can adequately be converted to PM₂.₅. In this study, a recently developed formulation for the calculation of surface PM₂.₅ concentrations using satellite data is introduced and applied to reconstruct a PM₂.₅ time series over China from 2000 to 2015. The formulated model is also used to explore the PM₂.₅ driving factors related to anthropogenic or meteorological parameters in this historical period. The results show that the annually averaged PM₂.₅ over China’s polluted regions increased rapidly between 2004 and 2007 (with an average rate of 3.07 μg m⁻³ yr⁻¹) to reach values of up to 61.1 μg m⁻³ in 2007, and decreased from 2011 to 2015 with an average rate of -2.61 μg m⁻³ yr⁻¹, to reach a value of 46.9 μg m⁻³ in 2015. The analysis shows that the increase in PM₂.₅ before 2008 was mainly associated with increasing anthropogenic factors, further augmented by the effect of meteorological influences. However, the decrease in PM₂.₅ after 2011 is mainly attributed to the effect of pollution control measures on anthropogenic factors, whereas the effects of meteorological factors have continued to increase since 2000. The results also suggest that further reduction in anthropogenic emissions is needed to accelerate the decrease in PM₂.₅ concentrations to reach the target of 35 μg m⁻³ over major polluted areas in China before 2025.
显示更多 [+] 显示较少 [-]