Estimation of canopy water content with MODIS spectral index

Zuoning Jiang; Lin Li; Susan L. Ustin

doi:10.1117/12.826277

20 August 2009 Estimation of canopy water content with MODIS spectral index

Zuoning Jiang, Lin Li, Susan L. Ustin

Proceedings Volume 7454, Remote Sensing and Modeling of Ecosystems for Sustainability VI; 74540V (2009) https://doi.org/10.1117/12.826277
Event: SPIE Optical Engineering + Applications, 2009, San Diego, California, United States

Abstract

Canopy water content is an important variable for forestry and agriculture management. This study was aimed at building calibration models to estimate vegetation canopy (VC) equivalent water thickness (EWT) from high temporal resolution and large areal coverage MODIS images. The models were developed for a semi-arid area in Arizona (SMEX04) and the best one was applied to MODIS images covering a forest area in Southern Indiana. EWT derived from hyperspectral data in the process of atmospheric correction was used for calibrating MODIS spectral indices. Tested in this study were four vegetation indices: Normalized Difference Water Index (NDWI), Shortwave Infrared Water Stress Index (SIWSI), Normalized Difference Vegetation Index (NDVI), and Enhanced Vegetation Index (EVI), which were designed based on either water (NDWI and SIWSI) or chlorophyll absorptions (NDVI and EVI). Validating these indices on field measured EWT for the SMEX04 site resulted in R² correlations of 0.7547, 0.7509, 0.7299 and 0.7547, respectively. According to regression equations, however, EWT estimated using NDWI and SIWSI shows a slope more close to 1 than those using NDVI and EVI when validated with ground measured EWT, thus showing a better prediction ability than the two chlorophyll indices. The SIWSI-EWT model was chosen to apply to a time series of MODIS images covering the Southern Indiana areas and the relationship of EWT derived from these images to precipitation was examined.

Citation Download Citation

Zuoning Jiang, Lin Li, and Susan L. Ustin "Estimation of canopy water content with MODIS spectral index", Proc. SPIE 7454, Remote Sensing and Modeling of Ecosystems for Sustainability VI, 74540V (20 August 2009); https://doi.org/10.1117/12.826277

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available