A study on the spatial-temporal patterns and influencing factors of atmospheric vulnerability in the Pearl River Delta

Atmospheric environmental assessment has emerged as a prominent area of research due to global climate change and regional atmospheric pollution issues. Accurate evaluation of atmospheric environmental vulnerability characteristics and understanding driving mechanisms are crucial for effective air pollution monitoring and prevention. This study focuses on the Pearl River Delta (PRD) region and employs the Vulnerability-Scoping-Diagram (VSD) model framework to establish an index system for assessing atmospheric environmental vulnerability based on exposure, sensitivity, and adaptability, combining the entropy value method and adopts Geographic Information System (GIS) for the time change and spatial evolution analysis, and finally utilizing the factor detection and interaction in Geodetector to explore the contribution degree of each driving factor of atmospheric environmental vulnerability and the exchange of influencing factors. The findings of this research are as follows: Firstly, the sensitivity index and resilience index of the atmospheric environment of the PRD exhibit an overall upward trend with fluctuations, while the exposure index demonstrates a pattern of initial increase, followed by a decrease, and subsequent increase with significant interannual variability. Secondly, the atmospheric environment vulnerability level of the PRD is primarily categorized as low and mild, with a negligible proportion of moderate vulnerability and no instances of severe or extreme vulnerability. The vulnerability index shows an initial increase followed by a subsequent decline from 2016 to 2020, indicating an overall improvement in the region's atmospheric environment. Thirdly, notable variations exist in the atmospheric environment vulnerability indices among the nine cities in the PRD, in which moderate vulnerability and low vulnerability are mainly concentrated in Guangzhou, Shenzhen, Foshan, and Dongguan in the central part of the PRD. lower vulnerability is primarily observed in the eastern and western regions of the PRD characterized by favorable natural environments and limited human interference, such as Huizhou, Zhaoqing, and Zhuhai. Finally, the atmospheric environment vulnerability of the PRD is the result of the combined effect of various driving factors, among which the urban built-up area, PM2.5 concentration, SO2 concentration, population density and the share of tertiary industry in GDP are the key drivers.