Significant increase in extreme heat events along an urban–rural gradient

Abstract

Abstract Cities worldwide are expecting more intense and frequent extreme heat events (EHEs) with climate change and urban growth. While previous studies have shown large intra-urban spatial variations in temperature, little is known regarding how EHEs were spatially distributed within a city. Here, taking Shenzhen, a rapidly urbanizing megacity in China as a case study, we examined the spatiotemporal pattern of EHEs, and further compared it with that of air temperature, using data collected from 85 weather stations from 2008 to 2017. We found: 1) Similar to air temperature, EHEs showed large spatial heterogeneity city-wide, which, however, was different from that of air temperature; 2) The differences in EHEs between urban and non-urban areas had significant increasing trends, with increasing rate of 0.50d/y (p