Thermal environment change and its socioeconomic drivers in Shanghai City during the 1990s
20世纪90年代上海市热环境变化及其社会经济驱动力

The urbanization process has significant environmental implications including reduction in evapotranspiration, promotion of more rapid surface runoff, increased storage and transfer of sensible heat, and reduction of air and water quality. The thermal environment is an important factor for the urban eco-environment. There are two main aspects of drivers for urban thermal environment dynamic, land cover change and human socioeconomic activities. This paper first retrieves the urban land surface temperature of Shanghai city using Landsat imagery data (TM/ETM+) on a pixel-by-pixel basis, then discusses the urban thermal environment dynamic and its drivers in Shanghai city during the 1990s. The results reveal the characters of the urban heat island effect. The extent of the heat island expands distinctly and the thermal environment worsens, however, the strength of heat island in the center of the urban area decreases and its spatial pattern becomes more complex. There are many different scales of socioeconomic drivers and synthesis interactions for the thermal environment dynamic. The rapid sprawling of the urban built-up area is the apparent driver of the expanding heat island. To improve the thermal environment in the urban center, decreasing population density is a synthesis driver, but the change of energy consumption patterns represented by industry is the key driver. Man-made countermeasures are the most effective means to change the pattern of thermal radiation and storage by increasing green vegetation cover and decreasing impervious surfaces.