Have government environmental auditing contributed to the green transformation of Chinese cities?

Faced with growing ecological problems, governments around the world are increasingly focusing on improving ecology and the environment. The topic of urban green transformation has attracted a great deal of research. However, not much of it has focused on the effectiveness of government environmental auditing, especially from the perspective of its role in sustainable governance. This article takes 285 cities in China from 2009 to 2020 as the research scale. It innovatively measures government environmental audits with dual indicators and uses System Gaussian Mixture Model (SGMM) to estimate that government environmental audits significantly promote urban green transformation, and the impact of "whether to implement government environmental auditing" is greater than the "intensity of government environmental auditing". The results show that government environmental audit intensity has a stronger impact on urban green transformation in eastern cities. In contrast, environmental audit coverage has a stronger impact in western cities. Moreover, the effect of government environmental auditing on green transformation is more significant in small and medium-sized cities and key environmental protection cities than in large cities and non-key environmental protection cities, respectively. Government environmental auditing could facilitate urban green transformation by restraining local government behavior, forcing green technology innovation, and promoting industrial structural upgrading. In addition, the intensity of government environmental auditing can better act on green transformation through the fore-mentioned mechanisms. It can play a crucial role in green technology innovation.