This function estimates the long wave outgoing radiation using the Stefan-Boltzmann equation.
outLWradiation(LAI, Ts)raster layer with leaf area index. See LAI()
Land surface temperature. See surfaceTemperature()
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
Other net radiation related functions: LAI,
  METRICtopo, SWtrasmisivity,
  albedo, incLWradiation,
  incSWradiation, netRadiation,
  soilHeatFlux, solarAngles,
  surfaceTemperature