Satellite-Based Energy Balance for Mapping Evapotranspiration with Internalized Calibration (METRIC)—Model

作者：Richard G. Allen, Masahiro Tasumi, Ricardo Trezza · 发表于：Journal of Irrigation and Drainage Engineering · 年份：2007 · DOI：10.1061/(asce)0733-9437(2007)133:4(380) · 被引用次数：1962 · 研究领域：Plant Water Relations and Carbon Dynamics、Hydrology and Watershed Management Studies、Solar Radiation and Photovoltaics

Mapping evapotranspiration at high resolution with internalized calibration (METRIC) is a satellite-based image-processing model for calculating evapotranspiration (ET) as a residual of the surface energy balance. METRIC uses as its foundation the pioneering SEBAL energy balance process developed in The Netherlands by Bastiaanssen, where the near-surface temperature gradients are an indexed function of radiometric surface temperature, thereby eliminating the need for absolutely accurate surface temperature and the need for air-temperature measurements. The surface energy balance is internally calibrated using ground-based reference ET to reduce computational biases inherent to remote sensing-based energy balance and to provide congruency with traditional methods for ET. Slope and aspect functions and temperature lapsing are used in applications in mountainous terrain. METRIC algorithms are designed for relatively routine application by trained engineers and other technical professionals who possess a familiarity with energy balance and basic radiation physics. The primary inputs for the model are short-wave and long-wave (thermal) images from a satellite (e.g., Landsat and MODIS), a digital elevation model and ground-based weather data measured within or near the area of interest. ET “maps” (i.e., images) via METRIC provide the means to quantify ET on a field-by-field basis in terms of both the rate and spatial distribution. METRIC has some significant advantages over many tr...