momentumRoughnessLength: Calculates Momentum Roughness Length

In ffuentesp7/METRICforR: Actual Evapotranspiration with Energy Balance models

Description

this function estimates Momentum Roughness Length (Zom) from the average vegetation height around the weather station.

Usage

momentumRoughnessLength(method = "short.crops", LAI, NDVI, albedo, a, b,
  fLAI.Perrier, h.Perrier, mountainous = FALSE, surface.model)

Arguments

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).
LAI	rasterLayer with Leaf Area Index. See LAI(). Only needed for method = "short.crops"
NDVI	rasterLayer with Normalized Difference Vegetation Index. Only needed for method = "custom"
albedo	broadband surface albedo. See albedo()
a	"a" coefficients for Allen (2007) custom function to estimate Momentum roughness length. Only needed for method = "custom"
b	"b" coefficients for Allen (2007) custom function to estimate Momentum roughness length. Only needed for method = "custom"
fLAI.Perrier	proportion of LAI lying above h/2. Only needed for method = "Perrier"
h.Perrier	crop height in meters. Only needed for method = "Perrier"
mountainous	empirical adjustment for effects of general terrain roughness on momentum and heat transfer. See Allen (2007)
surface.model	surface model with a RasterLayer called "Slope" needed is mountainous = TRUE. See surface.model()

Author(s)

Guillermo Federico Olmedo

de la Fuente-Saiz, Daniel

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

Pocas, I., Paco, T.A., Cunha, M., Andrade, J.A., Silvestre, J., Sousa, A., Santos, F.L., Pereira, L.S., Allen, R.G., 2014. Satellite-based evapotranspiration of a super-intensive olive orchard: Application of METRIC algorithms. Biosystems Engineering 128, 69-81. doi:10.1016/j.biosystemseng.2014.06.019

Santos, C., Lorite, I.J., Allen, R.G., Tasumi, M., 2012. Aerodynamic Parameterization of the Satellite-Based Energy Balance (METRIC) Model for ET Estimation in Rainfed Olive Orchards of Andalusia, Spain. Water Resour Manage 26, 3267-3283. doi:10.1007/s11269-012-0071-8

ffuentesp7/METRICforR documentation built on May 15, 2019, 11:57 a.m.