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Performs fourSAIL2 + PROSPECT simulation based on a set of combinations of input parameters

foursail2.Rd

Performs fourSAIL2 + PROSPECT simulation based on a set of combinations of input parameters

Usage

foursail2(
  LUT_GB = NULL,
  inputLUT,
  rsoil,
  PROSPECTversion = "PRO",
  FieldObserv = NULL,
  LeafModel = NULL
)

Arguments

LUT_GB

dataframe Includes distribution of biophysical parameters used as green vegetation (first column). Includes distribution of biophysical parameters used (second column)

inputLUT

LUT table with distribution of biophysical parameters used as input parameters in the model

rsoil

numeric. Soil reflectance

PROSPECTversion

Legacy switch, kept for backward compatibility: 'PRO' or anything else ('D'). Ignored if LeafModel is given.

FieldObserv

logical/NULL. If NULL (default), the "green vegetation" leaf optics are taken from inputLUT itself (i.e. the same leaf spectrum used for the main canopy), overriding whatever LUT_GB[1,] would otherwise give. If not NULL, the green/brown vegetation leaf optics are taken as computed from LUT_GB instead – for matching a field-observed green/brown fraction defined independently of inputLUT.

LeafModel

character. One of 'PROSPECT-PRO', 'PROSPECT-D', 'Liberty', 'Fluspect-B', 'Fluspect-B-Cx' – same 5 leaf models foursail and inform support. Defaults to PROSPECTversion-derived value if not given.

Value

list. rdot,rsot,rddt,rsdt rdot: hemispherical-directional reflectance factor in viewing direction rsot: bi-directional reflectance factor rsdt: directional-hemispherical reflectance factor for solar incident flux rddt: bi-hemispherical reflectance factor alfast: canopy absorptance for direct solar incident flux alfadt: canopy absorptance for hemispherical diffuse incident flux

References

Verhoef W & Bach H, 2007. Coupled soil–leaf-canopy and atmosphere radiative transfer modeling to simulate hyperspectral multi-angular surface reflectance and TOA radiance data. Remote Sensing of Environment, 109:166-182. doi:10.1016/j.rse.2006.12.013

Verhoef W, Jia L, Xiao Q & Su Z, 2007. Unified optical-thermal four-stream radiative transfer theory for homogeneous vegetation canopies. IEEE Transactions in Geosciences and Remote Sensing, 45:1808–1822. https://doi.org/10.1109/TGRS.2007.895844

Jacquemoud S, Verhoef W, Baret F, Bacour C, Zarco-Tejada PJ, Asner GP, François C & Ustin SL, 2009. PROSPECT+ SAIL models: A review of use for vegetation characterization. Remote Sensing of Environment, 113:S56–S66. https://doi.org/doi:10.1016/j.rse.2008.01.026

Berger K, Atzberger C, Danner M, D’Urso G, Mauser W, Vuolo F & Hank T 2018. Evaluation of the PROSAIL Model Capabilities for Future Hyperspectral Model Environments: A Review Study. Remote Sensing, 10:85. https://doi.org/10.3390/rs10010085

Authors:

Verhoef W.

Bach H.

Authors of the R version:

Jean-Baptiste Feret

The fourSAIL model is based on a version provided by Wout Verhoef et al. (2007)

original version downloadable at http://teledetection.ipgp.jussieu.fr/prosail/

Improved and extended version of SAILH model that avoids numerical singularities and works more efficiently if only few parameters change.