DocumentCode :
84093
Title :
An LUT-Based Inversion of DART Model to Estimate Forest LAI from Hyperspectral Data
Author :
Banskota, Asim ; Serbin, Shawn P. ; Wynne, Randolph H. ; Thomas, Valerie A. ; Falkowski, Michael J. ; Kayastha, Nilam ; Gastellu-Etchegorry, Jean-Philippe ; Townsend, Philip A.
Author_Institution :
Geospatial & Environ. Anal. Program, Virginia Polytech. Inst. & State Univ., Blacksburg, VA, USA
Volume :
8
Issue :
6
fYear :
2015
fDate :
Jun-15
Firstpage :
3147
Lastpage :
3160
Abstract :
The efficient inversion of complex, three-dimensional (3-D) radiative transfer models (RTMs), such as the discrete anisotropy radiative transfer (DART) model, can be achieved using a look-up table (LUT) approach. A pressing research priority in LUT-based inversion for a 3-D model is to determine the optimal LUT grid size and density. We present a simple and computationally efficient approach for populating an LUT database with DART simulations over a large number of spectral bands. In the first step, we built a preliminary LUT using model parameters with coarse increments to simulate reflectance for six broad bands of Landsat Thematic Mapper (TM). In the second step, the preliminary LUT was compared with the TM reflectance, and the optimal input ranges and realistic parameter combinations that led to simulations close to Landsat spectra were then identified. In the third step, this information was combined with a sensitivity study, and final LUTs were built for the full spectrum of Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) narrow bands and six Landsat broad bands. The final LUT was inverted to estimate leaf area index (LAI) in northern temperate forests from AVIRIS and TM data. The results indicate that the approach used in this study can be a useful strategy to estimate LAI accurately by DART model inversion.
Keywords :
forestry; geophysical image processing; hyperspectral imaging; inverse problems; radiative transfer; table lookup; vegetation mapping; 3D model; AVIRIS data; AVIRIS narrow bands; Airborne Visible/Infrared Imaging Spectrometer; DART model; DART simulations; LUT-based inversion; Landsat Thematic Mapper; Landsat broad bands; Landsat spectra; RTM; TM data; TM reflectance; coarse increments; complex three-dimensional radiative transfer models; discrete anisotropy radiative transfer; efficient inversion; forest LAI; hyperspectral data; leaf area index; look-up table approach; model parameters; northern temperate forests; optimal LUT grid size; spectral bands; Biological system modeling; Computational modeling; Earth; Remote sensing; Satellites; Solid modeling; Table lookup; Hyperspectral remote sensing; Landsat; imaging spectrometer; inversion methods; look-up-table (LUT); radiative transfer;
fLanguage :
English
Journal_Title :
Selected Topics in Applied Earth Observations and Remote Sensing, IEEE Journal of
Publisher :
ieee
ISSN :
1939-1404
Type :
jour
DOI :
10.1109/JSTARS.2015.2401515
Filename :
7052313
Link To Document :
بازگشت