Research on Urban Heat Island Effect Based on Landsat TM5 Images in Chuxiong City
PENG Yan-mei et al (Chuxiong Normal University,Chuxiong,Yunnan 675000)
Urbanization changed the land cover and ground hot environment deeply,as a result,the urban heat island effect became more and more obvious. The urban heat island effect of Chuxiong City in recent 20 years was discussed,based on the land surface temperature that retrieved from 3 band 6 data of Landsat TM5 images and real-time meteorological data at the satelite pass and recent year-book using Mono-window algorithm model in the spatial modeler of Erdas Imagine. In January of 1989,the temperature of urban building area was 0.50 ℃ higher than suburb. In December of 1999,the temperature of urban building area was 1.10 ℃ higher than that of suburb and the building area temperature of new town was 0.70 ℃ higher than that of old town. In March of 2007,the temperature of urban area was 1.35 ℃ higher than that of suburb and the temperature of new town was 0.10 ℃ higher than that of old town. From 1989 to 2007,urban heat island intensity become larger,temperature difference of new town and old town reduced but urban area and suburb increased,old city temperature gradually increased. The city high-temperature zone changed from town generally high to the west of old town and industrial area. Urdan high-temperature zone significantly affected by human activities,topography and industry development. Low-temperature zone changed from sporadic urban distribution to along with Longchuan River distribution. The water and green land had great contributions to the adjustment of urban temperature.