Acta Geographica Sinica ›› 2019, Vol. 74 ›› Issue (11): 2342-2357.doi: 10.11821/dlxb201911011

• Climate Change and Ecological Environment • Previous Articles     Next Articles

Impacts of urbanization on spatio-temporal variations of temperature over the Pearl River Delta

WU Zixuan1,2,3,ZHANG Qiang1,2,3(),SONG Changqing1,2,3,ZHANG Fen4,ZHU Xiudi1,2,3,SUN Peng5,FAN Keke1,2,3,YU Huiqian1,2,3,SHEN Zexi1,2,3   

  1. 1. Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education, Beijing Normal University, Beijing 100875, China
    2. State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875, China
    3. Academy of Disaster Reduction and Emergency Management, Beijing Normal University, Beijing 100875, China
    4. Key Laboratory of Western China's Environmental Systems, Ministry of Education, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China
    5. School of Geography and Tourism, Anhui Normal University, Wuhu 241000, Anhui, China
  • Received:2018-06-19 Revised:2019-07-01 Online:2019-11-25 Published:2019-11-01
  • Contact: ZHANG Qiang E-mail:zhangq68@bnu.edu.cn
  • Supported by:
    National Natural Science Foundation of China(41771536);National Natural Science Foundation of China(41601023);Creative Research Groups of National Natural Science Foundation of China(41621061);National Science Foundation for Distinguished Young Scholars of China(51425903)

Abstract:

Daily temperature data at 21 stations across the Pearl River Delta during the period of 1967-2015 were selected, and these stations were divided into urban stations and suburban stations based on population, population density and DMSP/OLS data. Meanwhile, spatio-temporal variations due to urbanization were investigated by comparing the temperature changes at urban and suburban stations. The results show that: (1) In the past 50 years, the annual average temperature, the average maximum temperature and the average minimum temperature in the Pearl River Delta region increased significantly, and the average minimum temperature increased at the highest rate, or 1.05-1.16 times of the average temperature and 0.95-1.32 times of the average maximum temperature, respectively. Among them, the seasonal difference of annual average temperature change rate is generally manifested as the strongest temperature increase in autumn and winter, with the temperature increase rate higher than 0.3 ℃/10a, and the temperature increase rate is weaker in spring and summer, with the temperature increase rate as low as 0.16 ℃/10a. (2) Using urban and Sea Surface Temperature (SST) comparison to study the urbanization effect, affected by urbanization, the annual average temperature of the Pearl River Delta is increasing by 0.096 ℃/10a. (3) Using urban and rural comparison to study the urbanization effect, from 1967 to 2015, urbanization leads to the temperature increase in urban areas. Generally speaking, urbanization contributes the most to the increase of average minimum temperature. Meanwhile, the seasonal difference in the contribution rate of urbanization to the annual average temperature change indicates that the increase rate is stronger in summer and winter, with the contribution rate higher than 11.8%, and lower in spring and autumn, with the contribution rate being only 4.46%. (3) The selection of stations division method, the different periods of urbanization development and time scale of research all lead to the uncertainty of the research results on the warming effect of urbanization. Different stations classification methods indicate that urbanization contributes the most to the increase of the minimum temperature, and for a longer time scale, the contribution rate of urbanization to the increase of the minimum temperature is up to 38.6%.

Key words: urbanization, temperature, station classification methods, Pearl River Delta