基于遥感的绍兴市热岛效应研究

Study on Heat Island Effect Based on Remote Sensing in Shaoxing City

利用LandsatTM影像,根据亮温计算公式,由灰度数据反演绍兴城区亮温;并对反演结果进行处理得到城区热岛图。热岛特点表现为绍兴城区整体上呈一热岛分布区,形成岛屿状的高温区域,高温中心集中于城区。由于绍兴市广泛的水域分布,对城市热岛影响明显,表现出高温区域与低值区域交错分布,说明城市水域能有效地降低地表温度和缓解城市热岛。将热岛图与绍兴市地图结合,发现绍兴市城市热岛面积随着城市的发展而扩大,但强度没有明显的改变。

In this paper, according to the brightness temperature computing mode, planetary brightness temperature in urban area of Shaoxing is retrieved by digital numbers derived from the Landsat TM images, which is processed to map the heat island effect. The results indicate that the urban area of Shaoxing appears to be a heat island distribution, which forms the islands shape in the high temperature region. The high temperature centers centralize in the urban. Widespread waters＂ distribution in the Shaoxing city produces obvious influence to city heat island. It displays interlacing distribution between the high temperature regions and the low value regions. Waters in the city can effectively bring down the surface temperature and relieve the heat island effect, which confirms the function of urban waters of reducing the temperature for the first time in the actual observation. Combining the heat island map with the map of Shaoxing, the scope of the heat island of Shaoxing expands with the development of the city while the intension of the heat island dose not enhance dramatically.