Climate extremes that severely impacted East China from summer 2020 to summer 2022

Heatwaves wreaked havoc across the Northern Hemisphere in summer 2022 and resulted in at least 15,000 deaths in Europe. Eastern China also experienced an unprecedentedly hot and dry summer. The maximum 2-m air temperature (Tmax) at around 300 national meteorological stations broke the historical record, and high temperature warnings sounded for 41 consecutive days. As a consequence, a devastating chain of disasters took shape. With Tmax >40°C, more than 270 million people suffered from heat stress, and there were hundreds of casualties reported due to thermoplegia. The long-lasting heatwaves and precipitation deficit subsequently led to severe drought in the Yangtze River basin. Decreased runoff reduced the hydropower generation by half in Sichuan Province, while the super heatwave led to a remarkable increase in electricity consumption and further aggravated the power shortage. Meanwhile, the drought induced a 10-day wildfire in Chongqing over August 17 to 26, 2022, that burned forests and emitted large quantities of pollutants and carbon into the air. Furthermore, Poyang Lake (the largest freshwater lake in China) lost more than 75% of its water in the summer, and the out-of-season drought continued until November 9, when the water level was only 6.67 m, which broke the historical minimum. The severe heatwave and drought in summer 2022 significantly highlight the importance and necessity to better understand climate extremes in China.