Quantifying the cooling effect of river and its surrounding land use on local land surface temperature: A case study of Bahe River in Xi’an, China

Abstract

Rapid urbanization and unplanned development have posed a threat to the thermal environment in a country like China. The urban heat island (UHI) phenomenon is one of the most serious issues because of its strong relation to thermal comfort, air pollution, and public health. The water bodies, as an important component of the urban ecosystem, are generally considered a vital resource to mitigate the UHI. This study provides direct evidence with the help of satellite observation and field measurement data using the mono-window algorithm, spatial buffer analysis, and linear regression methods to explore how the stream water affects the local temperature variation. The results showed that Land use/cover change (LUCC) and Land surface temperature (LST) on both banks of the Bahe River changed significantly. The LST of the river was significantly massively reduced within the distance range of 300 to 500 m, and 400 to 600 m, with an average temperature dip from 3.7 to 2.8 °C, and from 3.2 to 1.7 °C respectively were during the summer on east and west river banks. In addition, the surrounding LUCC composition and configuration could strongly affect the maximum cooling scale. The results provide insights for urban planners and managers to arrange the LUCC composition between the river design in urban areas and the cooling effect demands.