摘要
空气动力学粗糙度是表征下垫面空气动力学特征的重要参数。雷达遥感是空气动力学粗糙度研究的一种有效手段。利用200G～2011年的22景多时相ALOSPALSAR数据，分析了北京市北部地区后向散射系数的方向及尺度特征，同时利用多层风速、风向观测资料计算得到了空气动力学粗糙度，并在不同尺度和方向上分析了两者的相关性，得出上风向扇形区域半径为2500m，夹角为30。时扇形区域内的后向散射系数与空气动力学粗糙度的相关性最大，表明SAR图像可以有效表征城市下垫面地表的空气动力学粗糙特性。这一结论为城市空气动力学粗糙度雷达遥感反演提供了重要基础，将为大气边界层模型和区域气候模型提供更精确的输入。
Aerodynamic roughness is a very important parameter to represent the aerodynamic characters in urban areas.Radar remote sensing is considered to be an effective means for aerodynamic roughness retrieval.This paper analyzed the direction features and scale characteristics of backscattering coefficient in northern Beijing by using 22 ALOSPALSAR images from 2006 to 2011.And aerodynamic roughness was calculated by the gradient data of wind speed and direction.The relationship between aerodynamic roughness and backscattering coefficient was analyzed in different scales and orientations.The results showed that the correlation coefficient was reached maximum when the radius of windward sector domain was 2 500 m and included angle was 30°.It indicated that the SAR images can ef- fectively characterize the aerodynamic characters. The resultsprovidedimportant basis for the inversion of aerody- namic roughness by using SAR images, which will provide more accurate parameters for regional climate model and atmospheric boundary layer model.
作者
沙敏敏
张风丽
符喜优
王国军
邵芸
Sha Minmin Zhang Fengli Fu Xiyou Wang Guojun Shao Yun(Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences ,Beijing 100101 ,China University of Chinese Academy of Sciences ,Beijing 100049 ,China)
出处
《遥感技术与应用》
CSCD
北大核心
2016年第5期855-863,共9页
Remote Sensing Technology and Application
基金
国家自然科学基金资助项目“城市下垫面粗糙特性时空特征雷达遥感监测及气候环境影响研究”(41671359),“复杂散射机制场景的SAR图像认知方法研究”(61471358),“可控环境下多层介质目标微波特性全要素测量与散射机理建模”(41431174)
中国科学院知识创新工程重要方向项目“典型地物微波特性知识库构建与开发”(KZCX2-EW-320)
国家863计划项目“典型地物目标后向散射特性数据库”(2011AA120403)
