Tang Bo-Hui, Li Zhao-Liang, Bi Yuyun
State Key Lab of Resources and Environmental Information System, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China.
Opt Express. 2009 Mar 2;17(5):3173-82. doi: 10.1364/oe.17.003173.
This work addressed the estimate of the directional emissivity in the mid-infrared (MIR) channel around 4.0 microm from MODIS data. A series of bidirectional reflectances in MODIS channel 22 (3.97 mum) were retrieved using the method developed by Tang and Li (Int. J. Remote Sens. 29, 4907, 2008) and then were used to estimate the directional emissivity in this channel with the aid of the BRDF model modified by Jiang and Li (Opt. Express 16, 19310, 2008). To validate the estimated directional emissivity, a cross-comparison of MODIS derived emissivities in channel 22 using the proposed method were performed with those provided by the MODIS land surface temperature/emissivity product MYD11B1 data. The results show that the proposed method for estimating the directional emissivity in MIR channel gives results comparable to those of MYD11B1 product with a Mean Error of -0.007 and a Root Mean Square Error of 0.024.
这项工作利用中分辨率成像光谱仪（MODIS）数据，对4.0微米左右中红外（MIR）通道的方向发射率进行了估算。利用Tang和Li（《国际遥感学报》29, 4907, 2008）开发的方法，获取了MODIS第22通道（3.97微米）的一系列双向反射率，然后借助Jiang和Li（《光学快报》16, 19310, 2008）修正的双向反射分布函数（BRDF）模型，估算该通道的方向发射率。为验证估算的方向发射率，将利用所提方法得到的MODIS第22通道发射率，与MODIS陆地表面温度/发射率产品MYD11B1数据提供的发射率进行交叉对比。结果表明，所提的估算MIR通道方向发射率的方法，其结果与MYD11B1产品的结果相当，平均误差为-0.007，均方根误差为0.024。
