Impacts of impervious surface spatial patterns on surface heat island intensity in Chinese cities

Expansion of impervious surface area (ISA) due to rapid urbanization affects crucially the surface urban heat island intensity (SUHII) in China, but spatial patterns of impervious surface area and impact on SUHII remain to be studied． Here in this article satellite Land Surface Temperature (LST) data and high-resolution ISA data from 31 cities in China are used to comprehensively analyze effects of total area, aggregation, patch density and landscape shape of impervious surface, as well as impact of population and NDVI differences on SUHII． Significant spatial and seasonal variations in daytime SUHII are revealed, with decreasing intensity from south to north, but the pattern is exactly the opposite at night． Total area, aggregation, and landscape shape of ISA have a positive correlation with SUHII, but patch density has a negative correlation with SUHII． A stepwise multiple linear regression model reveals that indicators of landscape structure, population, and NDVI can explain 63.7% and 57.0% of changes in summer day and night SUHII, and 78.6% and 39.8% of changes in winter day and night SUHII． The aggregation index and landscape shape index of the ISA are significantly correlated with daytime SUHII, total area index and aggregation index exert significant impact on nighttime SUHII. These data will help to optimize urban landscape structure and reduce impact of heat island effect on urban safety．