Evaluation of the Airborne CASI/TASI Ts-VI Space Method for Estimating Near-Surface Soil Moisture
AbstractHigh spatial resolution airborne data with little sub-pixel heterogeneity were used to evaluate the suitability of the temperature/vegetation (Ts/VI) space method developed from satellite observations, and were explored to improve the performance of the Ts/VI space method for estimating soil moisture (SM). An evaluation of the airborne ΔTs/Fr space (incorporated with air temperature) revealed that normalized difference vegetation index (NDVI) saturation and disturbed pixels were hindering the appropriate construction of the space. The non-disturbed ΔTs/Fr space, which was modified by adjusting the NDVI saturation and eliminating the disturbed pixels, was clearly correlated with the measured SM. The SM estimations of the non-disturbed ΔTs/Fr space using the evaporative fraction (EF) and temperature vegetation dryness index (TVDI) were validated by using the SM measured at a depth of 4 cm, which was determined according to the land surface types. The validation results show that the EF approach provides superior estimates with a lower RMSE (0.023 m3·m−3) value and a higher correlation coefficient (0.68) than the TVDI. The application of the airborne ΔTs/Fr space shows that the two modifications proposed in this study strengthen the link between the ΔTs/Fr space and SM, which is important for improving the precision of the remote sensing Ts/VI space method for monitoring SM. View Full-Text
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Fan, L.; Xiao, Q.; Wen, J.; Liu, Q.; Tang, Y.; You, D.; Wang, H.; Gong, Z.; Li, X. Evaluation of the Airborne CASI/TASI Ts-VI Space Method for Estimating Near-Surface Soil Moisture. Remote Sens. 2015, 7, 3114-3137.
Fan L, Xiao Q, Wen J, Liu Q, Tang Y, You D, Wang H, Gong Z, Li X. Evaluation of the Airborne CASI/TASI Ts-VI Space Method for Estimating Near-Surface Soil Moisture. Remote Sensing. 2015; 7(3):3114-3137.Chicago/Turabian Style
Fan, Lei; Xiao, Qing; Wen, Jianguang; Liu, Qiang; Tang, Yong; You, Dongqin; Wang, Heshun; Gong, Zhaoning; Li, Xiaowen. 2015. "Evaluation of the Airborne CASI/TASI Ts-VI Space Method for Estimating Near-Surface Soil Moisture." Remote Sens. 7, no. 3: 3114-3137.