The Suzhou urban as the research object, the surface brightness temperature was retrieved by the 1987,2005 and 2010 Landsat TM / ETM+thermal infrared band remote sensing images, then calculated the relative brightness temperature and the urban heat island ratio index, according to the relative brightness temperature, the Suzhou urban heat island effect was divided into four grades: green island, weak island, heat island and strong island, and compared the 3 periods urban heat island ratio index. The results show that: (1) with the urbanization process accelerated, the urban heat island ratio index has been rising in 1987-2010, the urban heat island effect is enhanced year by year; (2) the green island area and the strong island area in 1987-2010 are declining, are reduced by 23.82.km2and 8.75.km2, the weak island area and the heat island area are increasing, are increased by 22.69.km2and 9.83.km2; (3) the Suzhou urban expansion and the urban heat island expansion trend has the same space consistency in 1987-2010, while the urban area is sprawling, the urban heat island area is also expanding; (4) the urban vegetation and the urban heat island effect is a negative correlation in 1987-2010, appropriate to increase the urban green space for the mitigation of urban heat island effect has a positive effect.
Surface urban heat island effect and its relationship with urban expansion in Nanjing, China
