珠江三角洲城市群热环境空间格局动态  

Spatial characteristics and dynamic simulations of urban heat environment of cities in Pearl River Delta

作　　者：江学顶[1] 夏北成[1] 

机构地区：[1]中山大学环境科学与工程学院,广州510275

出　　处：《生态学报》2007年第4期1461-1470,共10页Acta Ecologica Sinica

基　　金：中山大学985工程环境与污染控制技术创新平台资助项目~~

摘　　要：以广州为中心的珠江三角洲城市群发展十分迅速，区域内热岛强度与规模日益加剧，受研究方法和技术的限制，热岛空间格局及其动态研究不深入。因此，研究城市特别是城市群热环境空间格局的日变化特征具有重要的现实意义和理论意义。采用遥感反演和中尺度模式MM5模拟的结果研究城市热力景观及其日变化规律，其中MM5模拟采用四重嵌套网格，最高分辨率为1km，遥感数据采用ETM＋的热红外波段。结果表明该区域热岛具有多中心的特征，两种方法得到的热岛空间分布特征一致，其精度均较高，但遥感反演结果更为细致。两者的空间格局与自相关性较接近，数值模拟结果的空间自相关程度呈近似余弦曲线变化；热力景观格局指数白天波动明显、夜间波动较小，且斑块数和景观形状指数白天大于夜晚，并在5：00出现小波峰；景观水平上的景观指数11：00～14：00出现最大值，夜间较小，其中景观分离度和面积一周长分维数在5：00出现小波峰，21：00出现拐点；下垫面性质、地表热量交换、局地环流等对热力景观格局影响较大。以数值模拟为基础，借助3S技术能较好研究城市热力景观空间格局的日变化特征。Influences of the urban heat island （UHI） became more and more serious in the industrial areas of Pearl River Delta. Spatial patterns and dynamic characteristics of the UHI were not well understood because of limitation of research methods and techniques used for this type of study. The spatial patterns of meteorological conditions were important for the formation of the UHI. Spatial patterns of urban heat environment were simulated by the fifth generation Penn State/NCAR Mesoscale Model （MM5） and studied using data retrieved from remote sensing （RS） images. Thermal landscape was described by using classic landscape indices. The non-hydrostatic mesoscale model （MM5） simulations were conducted using four nested domains, and used to simulate the thermal environment. The finest mesh grid increment of the nesting was 1 km. The land surface temperature （LST） was retrieved by single sixth thermal infrared data of ETM ＋ at 11：00 am （local time） on Sep 14, 2000. The distributions of LST and urban heat island intensity （UHII） were similar between model simulations and RS data. It showed that there were several UHI centers in Pearl River Delta. The differences of temperature between simulated by MM5 and RS images and observed data from automatic weather stations （AWS） were roughly 1℃. LST distributions retrieved by ETM ＋ showed more fine-scale details than MM5 simulations. Wetland landscape, urban green-land, and river could break up UHI into segments. It revealed that these three types of land-use were important to define urban heat environment. Some small urban cold islands appeared near large parks, lakes, and reservoirs. The intensity of UHI was divided into six categories by temperature differences. The heterogeneity of thermal environment could be revealed by using the categories of UHI intensity. Therefore the thermal landscape types were defined with six types. By the methods of landscape ecology and GIS, the spatial pattern indices of thermal landscape from MM5 and RS w

关 键 词：城市热岛 中尺度模式MM5 热力景观 空间格局 日变化 

分 类 号：X16[环境科学与工程—环境科学]