Long-Term Air Pollution Characteristics and Multi-scale Meteorological Factor Variability Analysis of Mega-mountain Cities in the Chengdu-Chongqing Economic Circle

Abstract

Currently, air quality has become central to global environmental policymaking. As a typical mountain megacity in the Cheng-Yu region, the air pollution in Chongqing is unique and sensitive. This study aims to comprehensively investigate the long-term annual, seasonal, and monthly variation characteristics of six major pollutants and seven meteorological parameters. The emission distribution of major pollutants is also discussed. The relationship between pollutants and the multi-scale meteorological conditions was explored. The results indicate that particulate matter (PM), SO 2 and NO 2 showed a “U-shaped” variation, while O 3 showed an “inverted U-shaped” seasonal variation. Industrial emissions accounted for 81.84%, 58% and 80.10% of the total SO 2 , NOx and dust pollution emissions, respectively. The correlation between PM2.5 and PM10 was strong ( R = 0.98). In addition, PM only showed a significant negative correlation with O 3 . On the contrary, PM showed a significant positive correlation with other gaseous pollutants (SO 2 , NO 2 , CO). O 3 is only negatively correlated with relative humidity and atmospheric pressure. These findings provide an accurate and effective countermeasure for the coordinated management of air pollution in Cheng-Yu region and the formulation of the regional carbon peaking roadmap. Furthermore, it can improve the prediction accuracy of air pollution under multi-scale meteorological factors, promote effective emission reduction paths and policies in the region, and provide references for related epidemiological research. Graphical abstract Supplementary Information The online version contains supplementary material available at 10.1007/s11270-023-06279-8.

Variation characteristics and coordinated emission reduction of air pollutants in megacity of Chengdu-Chongqing economic circle under dual carbon goal

“…S5) [74]. Furthermore, the unique climatic features of this region are extremely low wind speeds (0.9-1.4 m/s), a high frequency of atmospheric inversions and high relative humidity (79-84%) all year round [10,[75][76][77]. The closed environment makes the stability of the atmospheric stratification in the basin boundary layer higher than that in other areas at the same latitude.…”

“…Recent population research have revealed that PM 2.5 exposure is related to reproductive and neurological diseases, while O 3 exposure is associated with cardiopulmonary disease and lung cancer [8,9]. Previous studies have shown that about 7 million premature deaths per year are due to air pollution [10,11]. Previous studies also indicate that about 98% of cities in developing countries fail to fulfill the air quality guidelines of World Health Organization (WHO) [12,13].…”

“…In special terrain such as basins and valleys, the task of high-efficiency control of environmental pollution in megacities is even more arduous. Due to the unique terrain and meteorological factors, rapid economic development and high emission sources, it is critical to explore the characteristics and formation mechanism of air pollutions in Chengdu [10,[70][71][72]. What's more, most of the existing studies are mostly limited to single pollutant (PM or O 3 ) and short-term (1-2 years of heavy pollution) studies, or focus on measurements of short-term events or case studies.…”