支持向量机的北京城市热岛模拟:热岛强度空间格局曲面模拟及其应用  

Spatial Simulation of Urban Heat Island Intensity Based on the Support Vector Machine Technique:A Case Study in Beijing

作　　者：占文凤[1] 陈云浩[1] 周纪[2,3] 李京[1] 

机构地区：[1]北京师范大学地表过程与资源生态国家重点实验室,北京100875 [2]电子科技大学地表空间信息技术研究所,四川成都610054 [3]遥感科学国家重点实验室,北京100101

出　　处：《测绘学报》2011年第1期96-103,共8页Acta Geodaetica et Cartographica Sinica

基　　金：国家自然科学基金(40771136;40701114);北京市优秀人才培养资助项目(20081D0503100254);北京师范大学自主科研基金(2009SAP-1);遥感科学国家重点实验室开放基金(OFSLRSS201003)

摘　　要：将支持向量机（SVM）曲面拟合算法引入城市热岛强度曲面模拟研究,以MODIS的地表温度产品（LST）数据为例,对2006~2008年北京地区城市热岛强度进行支持向量机（SVM）曲面拟合。敏感性分析和精度评价表明该算法精度较高,能够用来表征城市热岛的空间格局特征。应用结果表明,凭借该算法可对地表城市热岛制图。在年内和年际序列上,白天和夜间城市热岛容量均大致服从正弦周期性变化规律,但夜间热岛容量的年较差远小于白天。The surface fitting algorithm based on the support vector machine（SVM） technique was introduced.With the LST（land surface temperature） products from MODIS and after elimination of the data covered by clouds,757 images（274 and 483 ones for day and night,respectively） in Beijing metropolitan area from the year 2006 to 2008 were fitted one by one using the SVM technique.The sensitivity analysis and accuracy assessment both indicate that this algorithm is of high accuracy and capable to be used in depicting the spatial pattern of UHI（urban heat island）.Furthermore,by virtue of it,mapping of urban surface temperature becomes possible.The application results also show that,from an inter-annually perspective,UHI capacities during daytime and nighttime in time series are both generally subjected to periodic sinusoidal variation;however,the amplitude of annual variation of UHI capacity during nighttime is far less than that during daytime.This is because different driving factors dominate different patterns of UHI temporally and spatially in distinct seasons and illumination conditions.The SVM fitting of UHI intensity model presented in this paper pays more attention on the overall spatial features of UHI approximately,while ignoring the noise caused by random factors and the details of a weak surface temperature change;hence it is a powerful tool for investigating the spatial pattern of temperature distribution in the analysis of urban thermal environment.

关 键 词：城市地表 热红外遥感 城市热岛 支持向量机 曲面拟合 

分 类 号：P237[天文地球—摄影测量与遥感]