东北地区森林积雪的微波辐射亮温模拟分析  

Analysis of the Microwave Brightness Temperature Simulations of Snow-coverd Forest Areas in Northeast China

作　　者：王广蕊 李晓峰[1,3] 赵凯[1,3] 姜涛[1,3] 郑兴明[1,3] 杨建卫[1,2] 李雷[1,3] 靳梦杰[1,2] 武黎黎 Wang Guangrui;Li Xiaofeng;Zhao Kai;Jiang Tao;Zheng Xingming;Yang Jianwei;Li Lei;Jin Mengjie;Wu Lili(Northeast Institute of Geography and Agroecolog y ,Chinese Academy of Sciences, Changchun 130102,China;University of Chinese Academy of Sciences ,Beijing 100049,China;Changchun Jingyuetan Remote.Sensing Experiment Station ,Chinese Academy of Sciences ,Changchun 130102,China;School of Geographic Sciences,Xinyang Normal University,Xinyang 464000,China)

机构地区：[1]中国科学院东北地理与农业生态研究所,吉林长春130102 [2]中国科学院大学,北京100049 [3]中国科学院长春净月潭遥感实验站,吉林长春130102 [4]信阳师范学院地理科学学院,河南信阳464000

出　　处：《遥感技术与应用》2018年第6期1017-1029,共13页Remote Sensing Technology and Application

基　　金：国家自然科学基金项目"东北地区森林下雪深被动微波遥感反演的关键影响参数观测与研究"(41471289);国家自然科学基金青年项目"基于雪粒径演化过程的被动微波遥感雪深反演算法研究"(41701395);科技部国家科技基础资源调查专项"中国积雪特性及分布调查"(2017FY100500)

摘　　要：微波辐射亮温正向模拟是辐射传输模型反演积雪参数的关键步骤之一。以HUT模型为基础,针对森林冠层微波透过率这一关键的模型输入参数,在东北大小兴安岭典型森林积雪区进行了14个子区域(10km!10km)的地基遥感观测和森林参数取样观测实验,分别利用地基微波辐射计实测和森林材积量回归两种不同参数获取方法,得到实验观测区冬季森林透过率,并模拟了星载微波辐射计探测亮温(TsimuB)。通过对两种参数获取方法模拟亮温的相关性分析,说明在K波段水平极化条件下森林存在体散射效应(相关系数R2≤0.37),而Ka波段双极化和K波段垂直极化条件下,森林存在很弱或无体散射效应(相关系数R2≥0.53)。在此基础上,将TsimuB与FY3C MWRI观测的微波辐射亮温进行了差值比较,以MWRI的定标精度约以2 K为基准,提出了以偏差|Δ|≤3·"=6K为一致性判据准则。在K波段水平极化(H)与垂直极化(V)辐射计模拟的一致性为79%、82%,Ka波段的H和V为43%、50%;材积量模拟亮温的一致性是K波段H和V为57%、86%,Ka波段的H和V均为64%。结果表明:在HUT模型模拟森林积雪系统微波辐射亮度温度时,Ka波段积雪层散射引起的不确定性大于K波段森林散射引起的不确定性。通过数据分析,提出了HUT模型的适用性及东北地区森林—积雪真实性检验场的选址依据。Retrieving accurate quantitative snow parameters in forested regions is still a difficult problem for decades.The key to solve this problem is to improve the understanding of the physical mechanisms of the microwave radiation transfer process of forest-snow system.Forward simulation of microwave radiation brightness temperature is one of the crucial steps in retrieving snow parameters from radiative transfer model.To further comprehend the physical process of microwave radiation transfer of forest-snow system,ground-based remote sensing observation experiment 14 subregions (10 km×10 km) of the typical snow-covered forest areas in Daxing’anling and Xiaoxing’anling regions were carried out.The forest microwave transmissivity as animportant input parameter were acquired by two different methods,one is using ground-based microwave radiometer to observe(i.e.radiometer-simulation method) and the other is through an empirical regression formula to calculate with tree volume sampled data(i.e.volume-simulation method).And the detected brightness temperature of spaceborne microwave radiometer is simulated by HUT radiative transfer model(i.e.TB^simu ).The correlation analysis of the simulated result shows that there is a volume scattering effect(correlation coefficient R^2≤0.37)in the forest under the K-band horizontal polarization condition,while under the Ka-band dual polarization and K-band vertical polarization conditions,the forest volume scattering effect almost does not exist(correlation coefficient R^2≥0.53).On this basis,the difference between the simulated brightness temperature T simu B and that detected by FY3C MWRI is compared.based on the calibration accuracy(δ=2K) of MWRI,the deviation |Δ|≤3δ=6K is proposed as the consensus criterion to evaluation model simulation results.In radiometer-simulationprocess,the consistency of horizontal polarization (H) and vertical polarization (V) in K-band is 79%and 82%,respectively;and that of H and V in Ka-band is 43% and 50%,respectively.In volume-simulation p

关 键 词：积雪 亮温模拟 HUT模型 森林透过率 

分 类 号：TP79[自动化与计算机技术—检测技术与自动化装置]