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water (version 0.8)

calcAnchors: Select anchors pixels for H function

Description

automatically search end members within the satellite scene (extreme wet and dry conditions).

Usage

calcAnchors(image, Ts, LAI, albedo, Z.om, n = 1, aoi,
  anchors.method = "flexible", WeatherStation, plots = TRUE,
  deltaTemp = 5, minDist = 500, WSbuffer = 30000, verbose = FALSE)

Arguments

image

top-of-atmosphere landsat reflectance image

Ts

land surface temperature in K. See surfaceTemperature()

LAI

rasterLayer with Leaf Area Index. See LAI()

albedo

broandband surface albedo. See albedo()

Z.om

momentum roughness lenght. See momentumRoughnessLength()

n

number of pair of anchors pixels to calculate

aoi

area of interest to limit the search. If waterOptions(autoAOI) == TRUE, It'll use aoi object from .GlobalEnv

anchors.method

method for the selection of anchor pixels. "random" for random selection of hot and cold candidates according to CITRA-MCB method, or "best" for selecting the best candidates. And "flexible" for method with soft limits to the anchor pixel conditions.

WeatherStation

Optional. WeatherStation data at the satellite overpass. Should be a waterWeatherStation object calculated using read.WSdata and MTL file.

plots

Logical. If TRUE will plot position of anchors points selected. Points in red are selected hot pixels, blue are the cold ones and the black represents the position of the Weather Station

deltaTemp

deltaTemp for method "CITRA-MCBs" or "CITRA-MCBr"

minDist

minimun distance allowed for two anchor pixels of the same type (in meters).

WSbuffer

maximun distante to the Weather Station (in meters).

verbose

Logical. If TRUE will print aditional data to console

References

CITRA y MCB (com pers)

See Also

Other sensible heat flux functions: calcH, momentumRoughnessLength