Risks of Climate-Environment Cycle Deterioration Triggered by Extreme Weather: Quantifying the Impacts of the 2022 Compound Drought and Heatwave in Sichuan

Abstract

In summer 2022, Sichuan suffered an unprecedented compound heatwave-drought, cut-ting hydropower output and forcing a rapid coal-fired power ramp-up to secure supply, driving elevated emission intensities in its power sector. However, the fluctuations in power generation from thermal power and hydropower are significantly influenced by policy and economic factors. In meteorological-electrical coupling research, it is necessary to isolate the disturbances caused by major non-meteorological factors such as policy and economics on power generation to identify the true role of meteorological conditions. Therefore, this study proposes the “squeeze verification method,” which indirectly verifies the numerical confidence of the power time series variable under non-extreme weather conditions: by integrating CRU meteorological data, WIND energy data, and public environmental data, the ARIMA model is applied to quantify the power shortage amount caused purely by meteorological factors after stripping off the economic factors of policies in July–September 2022, which totaled 33,142 GWh, as well as the increase in thermal power generation, which amounted to 6806 GWh. Using localized emission factors, we calculated implicit emission increases: NOx dominated pollutant growth, while extra CO2 emissions accounted for 8.16% of annual power-sector carbon emissions. This study further uncovered synergistic environmental risks tied to emergency coal-fired power generation. These risks include elevated air pollutant and CO2 emissions, aggravated ozone pollution, and a reinforced positive feedback loop that intensifies the extreme weather cycle. Finally, we propose targeted preventive strategies to mitigate these cascading environmental risks and ensure the sustainable development of the energy system.