Abstract:
Based on the Landsat TM remote sensing images from 1990 to 2006, the relationship between different types of underlying surfaces and Urban Heat Island (UHI) by analyzing various underlying surfaces from different radius circular buffer zones (with Hefei Weather Station as their center) and their corresponding air temperatures (annual average temperaeure, maximum temperaeure,minimum temperaeure, and fixed time data). It is found that a very strong positive correlation between construction land and UHI and a negative correlation between woodland/grassland and UHI. There is a relatively strong positive correlation between water body and UHI at night. The influence of different types of underlying surfaces on UHI varies with different hours everyday. As far as range of influence is concerned, construction land is within 6 km; woodland/grassland is within 4 km; farmland influence reaches its peak at 4 km; influence of water body reaches 8 km slowly. At the same time, through analyzing the relationship between yearly Land Use and Land Cover Change (LUCC) and UHI, the authors give more evidence of the vital effect laid by city development on UHI. There is a relatively strong correlation between the maximum temperature and the annual variation of heat island intensity at 1400 LST and the yearly variation of LUCC. By the way, UHI decreases dramatically after the moving out of Hefei Weather Station. At last, the possible reasons for how the correlation between different underlying surfaces and UHI can be formed are discussed.