Title :
Estimation of vegetation water content through GA-PLS modeling of modis reflectance data
Author :
Li, Lin ; Ustin, Susan L. ; Riaño, David ; Cheng, Yen-Ben
Author_Institution :
Dept. of Earth Sci., Indiana Univ., Bloomington, IN, USA
Abstract :
This work was aimed at investigating the effectiveness of genetic algorithms (GA) - partial least square (PLS) regression in estimation of canopy equivalent water thickness (EWT) from MODIS image data of the SMEX´04 site. Calibration of MODIS spectral variables (single bands, band ratios and curvatures) against the AVIRIS-derived EWT at a degraded resolution resulted in a high correlation (R2=0.77) and an equivalent well correlation was obtained for validation on the MODIS pixels not used in the calibration. The spectral variables used in the GA-PLS model include MODIS band 2 (841-875 nm), band 5 (1230-1250 nm), and band curvatures at MODIS band 4 (545-565 nm), band 1 (620-670 nm) and band 2. A caveat for applying these spectral variables to estimate EWT in other areas is that their applicability may depend on local environmental conditions.
Keywords :
genetic algorithms; geophysical signal processing; least squares approximations; regression analysis; remote sensing; vegetation; AVIRIS derived EWT; GA-PLS modeling; MODIS image data; MODIS reflectance data; MODIS spectral variables; SMEX´04 site; canopy EWT estimation; equivalent water thickness; genetic algorithms; partial least square regression; vegetation water content estimation; wavelength 1230 nm to 1250 nm; wavelength 545 nm to 565 nm; wavelength 620 nm to 670 nm; wavelength 841 nm to 875 nm; Calibration; Correlation; Least squares approximation; MODIS; Mathematical model; Matrix decomposition; Vegetation mapping; AVIRIS; Equivalent water thickness (EWT); GA-PLS; MODIS; SMEX´04;
Conference_Titel :
Geoscience and Remote Sensing Symposium (IGARSS), 2010 IEEE International
Conference_Location :
Honolulu, HI
Print_ISBN :
978-1-4244-9565-8
Electronic_ISBN :
2153-6996
DOI :
10.1109/IGARSS.2010.5653843
