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water (version 0.5)

METRIC.EB: Estimates Energy Balance using METRIC2010 Model

Description

Estimates Energy Balance using METRIC2010 Model

Usage

METRIC.EB(image.DN, WeatherStation, MTL, sat = "auto", thermalband, plain = TRUE, DEM, aoi, alb.coeff = "Tasumi", LST.method = "SC", LAI.method = "metric2010", Zom.method = "short.crops", anchors.method = "CITRA-MCB", n = 1, ETp.coef = 1.05, Z.om.ws = 0.0018, ESPA = FALSE, verbose = FALSE)

Arguments

image.DN
raw imagen in digital counts to evaluate
WeatherStation
Weather Station data, can be a waterWeatherStation object
MTL
Landsat metadata file
sat
Landsat satellite version. "L7" or "L8"
thermalband
Landsat low gain thermalband
plain
Logical. If TRUE surface is assumed plain
DEM
Digital Elevation Model of the study area. Not needed if plain = TRUE
aoi
SpatialPolygon object with limits of Area of interest
alb.coeff
coefficient to transform narrow to broad band albedo. See Details.
LST.method
Method for land surface temperature estimation. "SC" for single channel or "SW" for split window algorithm. "SW" is only available for L8. See water::surfaceTemperature
LAI.method
Method used to estimate LAI from spectral data. See Details.
Zom.method
method selected to calculate momentum roughness length. Use "short.crops" for short crops methods from Allen et al (2007); "custom" for custom method also in Allen et al (2007); Or "Perrier" to use Perrier equation as in Santos et al (2012) and Pocas et al (2014).
anchors.method
method to select anchor pixels. Currently only "CITRA-MCB" automatic method available.
n
number of pair of anchors pixels to calculate
ETp.coef
ETp coefficient usually 1.05 or 1.2 for alfalfa
Z.om.ws
momentum roughness lenght for WeatherStation. Usually 0.0018 or 0.03 for long grass
ESPA
Logical. If TRUE will look for espa.usgs.gov related products on working folder
verbose
Logical. If TRUE will print aditional data to console

Details

There are differents models to convert narrowband data to broadband albedo. You can choose alb.coeff ="Tasumi" to use Tasumi et al (2008) coefficients, calculated for Landsat 7; alb.coeff ="Liang" to use Liang Landsat 7 coefficients or "Olmedo" to use Olmedo coefficients for Landsat 8.

References

R. G. Allen, M. Tasumi, and R. Trezza, "Satellite-based energy balance for mapping evapotranspiration with internalized calibration (METRIC) - Model" Journal of Irrigation and Drainage Engineering, vol. 133, p. 380, 2007