Soil drying intensification increases the connection between dry and hot extremes in a changing climate

Abstract

Global warming intensifies dry and hot extremes as well as their cascade occurrences, leading to devastating impacts on the environment, economy, and society. However, the linkages between dry and hot extremes remain poorly understood. Here, we examine the soil drying characteristics prior to the occurrence of hot extremes to better understand the dynamic relationship between dry and hot extremes. We find that rapidly evolving dry extremes are more likely (43.22%−44.90%) to be followed by hot extremes compared to slowly evolving ones (31.99%−32.78%), with large disparities observed in the northern mid-high latitudes (≥30°N). This higher probability is associated with elevated vapor pressure deficit and increased radiation, coupled with reduced precipitation. We identify the significant role of land−atmosphere coupling in linking rapid soil dryness and hot extremes. Our findings underscore the increased risk of hot extremes following rapid soil dryness and provide insights into preparedness and adaptation strategies for cascading dry and hot hazards.