More extreme-heat occurrences related to humidity in China: Study

Atmospheric humidity is a crucial factor affecting the efficiency of evaporation, making the combination of hot and humid conditions more physiologically stressful than extreme dry-temperature conditions. The record-breaking extreme heat event in Europe in 2003, the rare extreme heat wave in Russia in 2010, and a long-duration heat wave in southern China in 2013, aside from the thousands of human casualties, all caused billions of dollars in economic losses. The co-occurrence of day and night heat extremes has attracted much attention in China because, with its vast population and many laborers engaged in outdoor work, the recent rapid increases in air temperature that have resulted in more frequent and intense heat waves pose particularly dangerous conditions across most of the country. According to this study, the anomalies of humidity play a more important role than those of temperature in the occurrence of extreme compound humid-heat events in most parts of China, but particularly in eastern regions. Since 1961, the human population and land areas of China have experienced strongly increasing compound heat extremes, with a faster rate of exposure to extreme compound humid-heat events than to extreme compound high-temperature events. More information: Wenyue He et al, More extreme-heat occurrences related to humidity in China, Atmospheric and Oceanic Science Letters. Citation: More extreme-heat occurrences related to humidity in China: Study retrieved 8 July 2023 from https://phys. org/news/2023-07-extreme-heat-occurrences-humidity-china.