Generating global Leaf Area Index from Landsat

Algorithm formulation and demonstration

Sangram Ganguly, Ramakrishna R. Nemani, Gong Zhang, Hirofumi Hashimoto, Cristina Milesi, Andrew Michaelis, Weile Wang, Petr Votava, Arindam Samanta, Forrest Melton, Jennifer L. Dungan, Eric Vermote, Feng Gao, Yuri Knyazikhin, Ranga B. Myneni

Research output: Contribution to journalArticle

69 Citations (Scopus)

Abstract

This paper summarizes the implementation of a physically based algorithm for the retrieval of vegetation green Leaf Area Index (LAI) from Landsat surface reflectance data. The algorithm is based on the canopy spectral invariants theory and provides a computationally efficient way of parameterizing the Bidirectional Reflectance Factor (BRF) as a function of spatial resolution and wavelength. LAI retrievals from the application of this algorithm to aggregated Landsat surface reflectances are consistent with those of MODIS for homogeneous sites represented by different herbaceous and forest cover types. Example results illustrating the physics and performance of the algorithm suggest three key factors that influence the LAI retrieval process: 1) the atmospheric correction procedures to estimate surface reflectances; 2) the proximity of Landsat-observed surface reflectance and corresponding reflectances as characterized by the model simulation; and 3) the quality of the input land cover type in accurately delineating pure vegetated components as opposed to mixed pixels. Accounting for these factors, a pilot implementation of the LAI retrieval algorithm was demonstrated for the state of California utilizing the Global Land Survey (GLS) 2005 Landsat data archive. In a separate exercise, the performance of the LAI algorithm over California was evaluated by using the short-wave infrared band in addition to the red and near-infrared bands. Results show that the algorithm, while ingesting the short-wave infrared band, has the ability to delineate open canopies with understory effects and may provide useful information compared to a more traditional two-band retrieval. Future research will involve implementation of this algorithm at continental scales and a validation exercise will be performed in evaluating the accuracy of the 30-m LAI products at several field sites.

Original languageEnglish
Pages (from-to)185-202
Number of pages18
JournalRemote Sensing of Environment
Volume122
Early online date9 Feb 2012
DOIs
Publication statusPublished - 1 Jul 2012
Externally publishedYes

Fingerprint

Landsat
leaf area index
Demonstrations
reflectance
surface reflectance
Infrared radiation
land surveying
exercise
canopy
bidirectional reflectance
atmospheric correction
moderate resolution imaging spectroradiometer
physics
forest cover
land cover
MODIS
understory
wavelengths
simulation models
near infrared

Cite this

Ganguly, S., Nemani, R. R., Zhang, G., Hashimoto, H., Milesi, C., Michaelis, A., ... Myneni, R. B. (2012). Generating global Leaf Area Index from Landsat: Algorithm formulation and demonstration. Remote Sensing of Environment, 122, 185-202. https://doi.org/10.1016/j.rse.2011.10.032
Ganguly, Sangram ; Nemani, Ramakrishna R. ; Zhang, Gong ; Hashimoto, Hirofumi ; Milesi, Cristina ; Michaelis, Andrew ; Wang, Weile ; Votava, Petr ; Samanta, Arindam ; Melton, Forrest ; Dungan, Jennifer L. ; Vermote, Eric ; Gao, Feng ; Knyazikhin, Yuri ; Myneni, Ranga B. / Generating global Leaf Area Index from Landsat : Algorithm formulation and demonstration. In: Remote Sensing of Environment. 2012 ; Vol. 122. pp. 185-202.
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Ganguly, S, Nemani, RR, Zhang, G, Hashimoto, H, Milesi, C, Michaelis, A, Wang, W, Votava, P, Samanta, A, Melton, F, Dungan, JL, Vermote, E, Gao, F, Knyazikhin, Y & Myneni, RB 2012, 'Generating global Leaf Area Index from Landsat: Algorithm formulation and demonstration', Remote Sensing of Environment, vol. 122, pp. 185-202. https://doi.org/10.1016/j.rse.2011.10.032

Generating global Leaf Area Index from Landsat : Algorithm formulation and demonstration. / Ganguly, Sangram; Nemani, Ramakrishna R.; Zhang, Gong; Hashimoto, Hirofumi; Milesi, Cristina; Michaelis, Andrew; Wang, Weile; Votava, Petr; Samanta, Arindam; Melton, Forrest; Dungan, Jennifer L.; Vermote, Eric; Gao, Feng; Knyazikhin, Yuri; Myneni, Ranga B.

In: Remote Sensing of Environment, Vol. 122, 01.07.2012, p. 185-202.

Research output: Contribution to journalArticle

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T2 - Algorithm formulation and demonstration

AU - Ganguly, Sangram

AU - Nemani, Ramakrishna R.

AU - Zhang, Gong

AU - Hashimoto, Hirofumi

AU - Milesi, Cristina

AU - Michaelis, Andrew

AU - Wang, Weile

AU - Votava, Petr

AU - Samanta, Arindam

AU - Melton, Forrest

AU - Dungan, Jennifer L.

AU - Vermote, Eric

AU - Gao, Feng

AU - Knyazikhin, Yuri

AU - Myneni, Ranga B.

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