Quantitatively evaluating the effect of urbanization on heat waves in China

Xiaojun Wu; Lunche Wang; Rui Yao; Ming Luo; Shaoqiang Wang; Lizhe Wang

doi:10.1016/j.scitotenv.2020.138857

Quantitatively evaluating the effect of urbanization on heat waves in China

Sci Total Environ. 2020 Aug 20:731:138857. doi: 10.1016/j.scitotenv.2020.138857. Epub 2020 May 5.

Authors

Xiaojun Wu¹, Lunche Wang², Rui Yao¹, Ming Luo³, Shaoqiang Wang¹, Lizhe Wang⁴

Affiliations

¹ Hunan Key Laboratory of Remote Sensing of Ecological Environment in Dongting Lake Area, School of Geography and Information Engineering, China University of Geosciences, Wuhan 430074, China; Hubei Key Laboratory of Critical Zone Evolution, School of Geography and Information Engineering, China University of Geosciences, Wuhan 430074, China.
² Hunan Key Laboratory of Remote Sensing of Ecological Environment in Dongting Lake Area, School of Geography and Information Engineering, China University of Geosciences, Wuhan 430074, China; Hubei Key Laboratory of Critical Zone Evolution, School of Geography and Information Engineering, China University of Geosciences, Wuhan 430074, China. Electronic address: wang@cug.edu.cn.
³ School of Geography and Planning, Guangdong Key Laboratory for Urbanization and Geo-simulation, Sun Yat-sen University, Guangzhou, China.
⁴ Faculty of Computer Science, China University of Geosciences, Wuhan 430074, China; Hubei Key Laboratory of Intelligent Geo-Information Processing, China University of Geosciences, Wuhan 430074, China.

PMID: 32402903
DOI: 10.1016/j.scitotenv.2020.138857

Abstract

In this study, the long-term trends and spatial characteristics of heat waves (HW) were analyzed using observations at a dense network of 2000 meteorological stations in China during 1961-2014. The contribution of urbanization to HW was quantitatively evaluated at the national scale based on a method of dynamically classifying urban and rural stations. The results based on different HW measures showed that HW in China became increasingly frequent, intense and longer, and emerged earlier and terminated later. More significant variation trends of HW were observed in southern and northern China, whereas relatively weaker and negative trends occurred in the Jianghuai-Plain region. The effect of urbanization on HW was evaluated in eight subregions of China, the results showed that the urbanization had an notable impact on the progression of HW. The urbanization contribution was pronounced in all subregions, especially in the southwestern, northern and southern China, where contributions were found to be >45%. In northwestern China, a negative urbanization effect was found in some HW measures, which was inferred to be related to the local dry climate. Overall, the contribution of urbanization to HW reached 30-50% for the urban areas of China. This study provided great insights in understanding the variations in extreme weather events and their relationships with urbanization.

Keywords: China; Heat waves; Spatial distribution; Temporal trend; Urbanization.