21 November 2012 Estimation of global ET-Index from satellite imagery for water resources management
Author Affiliations +
Abstract
This paper presents the algorithm to estimate the Evapotranspiration Index (ET-Index) developed for a research product of the 1st generation of the Global Change Observation Mission satellite for the Climate (GCOM-C1) satellite of the Japan Aerospace Exploration Agency (JAXA). The ET-Index is equivalent to a widely used "Crop Coefficient" in the field of irrigation engineering, defined as the actual evapotranspiration normalized for weather conditions. The ET-Index is convertible to an actual quantity of evapotranspiration using local weather data. In the proposed method, the ET-Index is estimated primarily by the land surface temperature image of a satellite, with some additional inputs including the Digital Elevation Model (DEM) and global wind speed reanalysis data. The algorithm estimates the ET-Index by using the surface temperature as an indicator of surface wetness, employing two extreme hypothetical surface conditions called "wet surface," defined as a surface having a zero sensible heat flux, and "dry surface," defined as the surface having a zero ET. A derived ET-Index map is widely applicable for water resources management in agriculture and environmental conservation. Applications of the proposed algorithm to Landsat and MODIS thermal images showed good performances in semi-arid regions in China and the western United States.
© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Masahiro Tasumi, Masahiro Tasumi, Reiji Kimura, Reiji Kimura, Masao Moriyama, Masao Moriyama, Richard G. Allen, Richard G. Allen, Aiko Fujii, Aiko Fujii, } "Estimation of global ET-Index from satellite imagery for water resources management", Proc. SPIE 8524, Land Surface Remote Sensing, 85240K (21 November 2012); doi: 10.1117/12.976283; https://doi.org/10.1117/12.976283
PROCEEDINGS
10 PAGES


SHARE
Back to Top