遥感地表温度空间分辨率降尺度研究  

Spatial Downscaling Research of the Remotely Land Surface Temperature

作　　者：郭会敏[1] 宫阿都[2,3] 何汝艳[1] 蒋金豹[1] 

机构地区：[1]中国矿业大学(北京)地球科学与测绘工程学院,北京100083 [2]北京师范大学民政部/教育部减灾与应急管理研究院,北京100875 [3]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

出　　处：《遥感信息》2015年第4期29-36,共8页Remote Sensing Information

基　　金：国家自然科学基金(40701114)

摘　　要：针对地表温度(LST)存在时空分辨率之间的矛盾这一难题,在已有的研究基础之上,对NDVI分层回归降尺度方法进行改进,利用各类别层次低分辨率LST同多个特征参数间的可决系数(R2)筛选出最优尺度因子以替换NDVI指数。以北京市为研究区,基于TM影像计算得到多个特征参数和LST数据,将模拟的低分辨率LST降尺度到多个分辨率层次,同目标LST进行精度验证。结果表明:(1)在全局和各类别层次上,根据R2筛选出的最优尺度因子均为UI指数;(2)在不同分辨率层次上,与全局策略和NDVI分层回归方法相比,UI分层回归方法的降尺度精度均最高;(3)随着分辨率的变化,在各特征参数与LST间方程系数的变化程度中,SAVI和NDBI要明显低于UI和NDVI,NDVI的变化程度略低于UI指数。Aiming at the problem that the spatial and temporal resolution of land surface temperature have the contradiction with each other,based on the existing research,this research made improvements on the NDVI stratified regression downscaling method.This paper used the coefficient of determination (R 2 )between low resolution LST and multiple related characteristic parameters as the optimal scaling factor’s screening index on each category level,and NDVI was replaced with the optimal scaling factor.Taking Beijing city as the research area,based on the Landsat TM images to calculate the multiple characteristic parameters and LST data,and downscaling the simulated low resolution LST to multiple resolution levels.The downscaled LST validated against the target LST.Results showed that:(1)in the global and each category level,the optimal scaling factors are all UI index according to the R 2 evaluation index;(2)in different resolution levels,compared with the global strategy and NDVI stratified regression downscaling method,the selected UI index stratified regression downscaling method proposes the highest precision;(3 )as the change of resolution,among the changing degree of fitted equation coefficients between different characteristic parameters and the LST,SAVI and NDBI index are clearly lower than UI and NDVI index,and the degree of change of NDVI is less slightly than UI index.

关 键 词：地表温度 降尺度 特征参数 最优尺度因子 分层回归 

分 类 号：TP732[自动化与计算机技术—检测技术与自动化装置]