BVOCs' role in dynamic shifts of summer ozone formation regimes across China and policy implications.

Abstract

Biogenic volatile organic compounds (BVOCs) are crucial players in atmospheric chemistry, significantly impacting the formation of tropospheric ozone (O₃). While China has made substantial strides in reducing anthropogenic VOC (AVOCs) emissions, O₃ levels persist, highlighting the complex interplay between biogenic and anthropogenic sources. A critical knowledge gap exists in understanding how BVOC emissions influence ozone formation regimes (OFRs) and how this knowledge can inform effective air quality policies. This study employs the Model of Emissions of Gases and Aerosols from Nature (MEGAN) version 3.2 and the Community Multiscale Air Quality Modeling System (CMAQ) version 5.3.3 models, combined with process analysis (PA) and the Integrated Source Apportionment Method (ISAM), to evaluate the impact of BVOC emissions on OFRs in China. The models simulate BVOC emissions and their effects on OFRs across various regions during July 2019. The findings highlight that BVOCs play a pivotal role in shifting OFRs, with significant implications for ozone mitigation strategies in China. The study suggests that effective ozone control measures must consider the dual impact of BVOCs and AVOCs, with tailored strategies for different regions and times of day. The study also proposes potential challenges in mitigating BVOC emissions and outlines future research directions for interdisciplinary collaboration to address the complexities of ozone pollution management. This research advances the understanding of BVOCs' roles in ozone formation dynamics and provides a foundation for developing more effective air quality management policies in China, especially as global greening and climate change continue to influence BVOC emissions.