A generalized split-window algorithm for retrieving land-surface temperature from space
A generalized split-window algorithm for retrieving land-surface temperature from space
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DOI：
10.1109/36.508406
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发表时间：
1996-07-01
影响因子：
8.2
通讯作者：
Dozier, J
中科院分区：
文献类型：
--
作者：
Wan, ZM;Dozier, J
提出了一种利用AVHRR和MODIS数据反演地表温度的广义分裂窗方法。精确的辐射传输模拟表明，分裂窗算法中的系数必须随观测角度而变化，如果我们要在整个扫描条带范围内实现约1 K的LST精度，（+/-55度）和陆地表面温度和大气条件的变化范围比海洋大得多，我们从辐射传输模拟的回归分析中得到这些系数，仿真结果表明，当大气水汽含量增加，视角大于45 °时，需要对分裂窗方法进行优化，将大气水汽含量的范围分离，较低的边界温度，和表面温度到易于处理的子范围。利用HIRS/2或MODIS大气探测通道反演的大气下边界温度和垂直柱水汽含量，可以确定分裂窗方法最佳系数的取值范围。这种新算法不仅能更准确地反演陆面温度，而且对发射率的不确定性和仪器量化误差不太敏感。
We propose a generalized split-window method for retrieving land-surface temperature (LST) from AVHRR and MODIS data, Accurate radiative transfer simulations show that the coefficients in the split-window algorithm for LST must vary with the viewing angle, if we are to achieve a LST accuracy of about 1 K for the whole scan swath range (+/-55 degrees from nadir) and for the ranges of surface temperature and atmospheric conditions over land, which are much wider than those over oceans, We obtain these coefficients from regression analysis of radiative transfer simulations, and we analyze sensitivity and error over wide ranges of surface temperature and emissivity and atmospheric water vapor abundance and temperature, Simulations show that when atmospheric water vapor increases and viewing angle is larger than 45 degrees, it is necessary to optimize the split-window method by separating the ranges of the atmospheric water vapor, lower boundary temperature, and the surface temperature into tractable subranges. The atmospheric lower boundary temperature and (vertical) column water vapor values retrieved from HIRS/2 or MODIS atmospheric sounding channels can be used to determine the range for the optimum coefficients of the split-window method, This new algorithm not only retrieves land-surface temperature more accurately, but is also less sensitive to uncertainty in emissivity and to instrument quantization error.