The impact of external uncertainty factors on the time-frequency and quantile effects of China’s clean energy stock market Index

This paper explores the impact mechanism of global risk factors on the Chinese clean energy stock market. Based on data from 2019 to 2024, the study applies wavelet coherence and quantile regression methods to systematically examine the effects of U.S. economic policy uncertainty (EPU), geopolitical risk (GPR), the CBOE volatility index (VIX), and the U.S. Treasury yield curve spread (T10Y3M) on the Chinese clean energy stock market. The findings reveal that the impacts of these risk factors exhibit significant time-varying and nonlinear characteristics. Specifically, the effect of the T10Y3M shifts from a negative impact at lower quantiles to a positive impact at higher quantiles; geopolitical risk maintains significant effects across multiple time scales; economic policy uncertainty primarily exerts its influence in the short and medium frequency bands; and market volatility shows intermittent strong correlations in the high-frequency domain. The results suggest that while the Chinese clean energy market retains a certain level of independence, it remains susceptible to global risk shocks under extreme market conditions. These findings provide new perspectives on understanding the risk transmission mechanisms of the clean energy market and offer valuable insights for investors’ risk management and policymakers’ market regulation.