摘要
利用MODIS热红外数据,在完成几何校正、辐射定标、大气校正、云检测等数据预处理后,利用分裂窗算法反演得到乌鲁木齐2000-2005年1,4,7,10月的地表温度空间数据。在分析典型热温场的基础上,进行了热岛的季节和昼夜变化特征研究。结果表明:时间上,乌鲁木齐在夏季的白天和全年四季的夜晚均存在明显的城市热岛现象;空间上,乌鲁木齐城市和附近的戈壁、荒漠温度较高,近处的中山区和远郊的高山区温度较低,区域内温差较大、热岛强度高。乌鲁木齐城市热岛虽与其他大城市热岛特征在时空分布规律上有较多相似之处,但也有其自身的特性:干旱区城市郊区下垫面较多为戈壁荒漠,因此城市热岛效应在日间并不明显,相反有时会出现"城市冷岛"现象。
Urban heat island is the most prominent characteristic of temperature affected by human activities, it has attracted the extensive interests all over the world because of its effect on global warming, and therefore it automatically leads to an academic craze in researching climate, ecology and environment. With the acceleration of urbanization, urban heat island results gradually the shortage of water resources in arid areas. The present situation in Urumqi City is that there is a severe restriction in urban development and threatening of residents＇health. Land surface temperature （LST） is one of the most important parameters in researching urban heat island （UHI）. In this study, the data of land surface temperature are derived based on split-window algorithm using thermal infrared bands of MODIS data. Moreover, the spatial macro-distribution of land surface temperature in the study area is analyzed, and the temporal characteristics of urban heat island effect in the daytime, at night and in different seasons are compared. The results reveal that there is a remarkable urban heat island effect in Urumqi. The spatial characteristics of land surface temperature show that there is a close correlation between the urban heat island effect and the types and functions of underlaying surface, and the high-temperature regions accord with the urban areas with busy traffic. The temporal characteristics of land surface temperature show that the underlaying surface in arid sub- urbs is mainly the deserts, and the temperature is high in the daytime. Therefore the urban heat island effect is not so significant in the daytime and even an urban cold island occurs sometimes. The urban heat island effect in Urumqi is significant only in the daytime in summer and at night all the year round. The maximum intensity of urban heat island occurs at night in summer. The temperature differences are 4～ 6 ℃ between the urban area and the near suburbs and 8 ～ 10 ℃ between the urban area and the far suburbs.
出处
《干旱区研究》
CSCD
北大核心
2007年第5期698-703,共6页
Arid Zone Research
基金
教育部重点项目(206163)
绿洲生态教育部重点实验室开放课题(XJDX0201-2006-07)
新疆大学校院联合项目(070196)
作者简介
吕光辉（1963-），男，博士，副教授，主要从事干旱区资源与环境问题研究．E-mail：ler@xju．edu．cn
