Estimates Energy Balance using METRIC2010 Model
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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 |
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 |
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.
Guillermo F Olmedo, guillermo.olmedo@gmail.com
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
Questions? Problems? Suggestions? Tweet to @rdrrHQ or email at ian@mutexlabs.com.
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