Errors analysis on temperature and emissivity determination from hyperspectral thermal infrared data.
Sensitivity analysis of temperature-emissivity separation method commonly applied to hyperspectral data to various sources of errors is performed in this paper. In terms of resulting errors in the process of retrieving surface temperature, results show that: (1) Satisfactory results can be obtained for heterogeneous land surfaces and retrieval error of surface temperature is small enough to be neglected for all atmospheric conditions. (2) Separation of atmospheric downwelling radiance from at-ground radiance is not very sensitive to the uncertainty of column water vapor (WV) in the atmosphere. The errors in land surface temperature retrievals from at-ground radiance with the DRRI method due to the uncertainty in atmospheric downwelling radiance vary from -0.2 to 0.6K if the uncertainty of WV is within 50% of the actual WV; (3) Impact of the errors generated by the poor atmospheric corrections is significant, implying that a well-done atmospheric correction is indeed required to obtain accurate at-ground radiance from at-satellite radiance for successful separation of land-surface temperature and emissivity.
OuYang
Xiaoying
X
State Key Lab. of Resources and Environmental Information System, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China.
Wang
Ning
N
Wu
Hua
H
Li
Zhao-Liang
ZL
D000465:Algorithms; D001272:Atmosphere / Q000032:analysis*; D004784:Environmental Monitoring / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013055:Spectrophotometry, Infrared / Q000379:methods*; D013696:Temperature; D013817:Thermography / Q000379:methods*