Spatiotemporal evolution of extreme hot and humid events in Hubei Province from 1985 to 2024 and their response to preceding extreme precipitation

Abstract

[Objective] In the context of global climate change, extreme hot and humid events have become more frequent and widespread, posing significant threats to human health, socioeconomic development, and ecosystems. Investigating the spatiotemporal evolution of extreme hot and humid events and their response patterns to preceding extreme precipitation provides a scientific basis for improving regional climate adaptation strategies and early warning systems for extreme weather events. [Methods] Based on ERA5 reanalysis data from 17 cities in Hubei Province from 1985 to 2024, extreme hot and humid events were identified using the simplified Wet-Bulb Globe Temperature(sWBGT) index. Trend tests, multiple regression, and other method were applied to systematically analyze the spatiotemporal evolution characteristics of extreme hot and humid events in the study area and their response mechanisms to extreme precipitation. [Results] (1) Extreme hot and humid events in Hubei Province exhibited a significant increasing trend, and their duration showed an upward trend, particularly for HS-EP events(hot and humid events with preceding extreme precipitation).(2) Extreme hot and humid events showed different spatial distribution patterns. The western region experienced high frequency(>80 times), long duration(>5.6 days), and low intensity(<35), while the central region exhibited low frequency(<70 times), short duration(<4.8 days), and high intensity(>36).(3) Preceding extreme precipitation played a regulatory role in extreme hot and humid events. The logarithmic ratios of three characteristics(frequency, duration, and intensity) between HS-EP events and HS-NEP events(hot and humid events without preceding extreme precipitation) were-1.200, 0.148, and-0.005, respectively.(4) The impact of preceding extreme precipitation showed notable lagged effects and regional differences, exhibiting an evolution pattern of “short-term suppression(1~2 days)-long-term enhancement(7~10 days)”[Conclusion] The findings reveal the spatiotemporal distribution patterns of extreme hot and humid events in Hubei Province and their response patterns to preceding precipitation, providing new insights into the interactive response mechanisms between regional extreme hot and humid events and extreme precipitation under global warming.

Keywords

extreme hot and humid events / extreme precipitation / spatiotemporal distribution / lagged effect / regional differences / spatiotemporal evolution / response mechanism / influencing factors