A study of Urban heat island intensity based on “local climate zones”: A case study in Fuzhou, China

Urban heat island intensity (UHII) is an important metric used in measuring Urban heat island (UHI) effect. Nevertheless, its quantitative measurement has not yet been clearly addressed. Due to the limitation of meteorological stations either in their number or location, the traditional method which calculates the temperature difference between urban and rural areas based on the meteorological station data fails to accurately describe the UHII of a city. In order to work out this problem, Steward and Oke proposed a classification schema - “Local Climate Zones” (LCZ). This paper applied the new framework of LCZ to the study of UHII in Fuzhou using remote sensing technology. Fuzhou has witnessed a rapid urban expansion process since the late 1970s. The fast expansion of the city has caused severe UHI phenomenon occurring in the city and thus to have become the top one furnace city in China. The study reveals that the remote sensing technology based LCZ can effectively distinguish the thermal contrasts among all LCZ classes. In addition, the LCZ can fully disclose the distribution patterns of UHI. In this study, we revealed a UHII
LCZ
of 6.73°C for Fuzhou city on 27 September 2015, which indicates an intensification of the UHI in the city.