Trend Analysis and Risk Evaluation of Summer Extreme Heat in Fuyang, Anhui Province

Herein, extreme heat was analyzed, and risk days of extreme heat and population exposure were evaluated using a heat index based on data from five observation stations in Fuyang, Anhui Province, China, during the summer of 1970–2022. The results show that extremely hot days exhibited an increasing trend of 1.33 d/10 a and the heat index also showed a growing trend. The increasing trends demonstrated by the heat index on weekends were obviously lower than those on weekdays, with the highest value observed at 1400 LST. Further analysis reveals that low-risk days of extreme heat in Fuyang during the summer of 1970–2022 showed a decreasing trend of 0.85 d/10 a. Meanwhile, the number of middle-risk days of extreme heat increased by 1.42 d/10 a. This shift indicates that extreme heat in summer over Fuyang changed from low risk to middle risk. Compared with the 1978–2000 base period, population exposure to extreme heat more than doubled during 2005–2022. It is showed that the climate factor contributed 75.06% to changes in population exposure, followed by the population factor (17.32%) and the interaction effect of population and climate (7.62%).