Drivers and Decoupling Effects of PM2.5 Emissions in China: An Application of the Generalized Divisia Index

Although economic growth brings abundant material wealth, it is also associated with serious PM2.5 pollution. Decoupling PM2.5 emissions from economic development is important for China's long-term sustainable development. In this paper, the generalized Divisia index method (GDIM) is extended by introducing innovation indicators to investigate the main drivers of PM2.5 pollution in China and its four subregions from 2008 to 2017. Afterwards, a GDIM-based decoupling index is developed to examine the decoupling states between PM2.5 emissions and economic growth and to identify the main factors leading to decoupling. The obtained results show that: (1) Innovation input scale and GDP are the main drivers for increases in PM2.5 emissions, while innovation input PM2.5 intensity, emission intensity, and emission coefficient are the main reasons for reductions in PM2.5 pollution. (2) China and its four subregions show general upward trends in the decoupling index, and their decoupling states turn from weak decoupling to strong decoupling. (3) Innovation input PM2.5 intensity, emission intensity, and emission coefficient contribute largely to the decoupling of PM2.5 emissions. Overall, this paper provides valuable information for mitigating haze pollution.