isothermal.Rn {bigleaf} | R Documentation |
Calculates the isothermal net radiation, i.e. the net radiation that the surface would receive if it had the same temperature than the air.
isothermal.Rn(
data,
Rn = "Rn",
Tair = "Tair",
Tsurf = "Tsurf",
emissivity,
constants = bigleaf.constants()
)
data |
Data.frame or matrix containing all required variables |
Rn |
Net radiation (W m-2) |
Tair |
Air temperature (degC) |
Tsurf |
Surface temperature (degC) |
emissivity |
Emissivity of the surface (-) |
constants |
sigma - Stefan-Boltzmann constant (W m-2 K-4) |
The isothermal net radiation (Rni) is given by:
Rni = Rn + \epsilon * \sigma * (Tsurf^4 - Tair^4)
where \epsilon
is the emissivity of the surface. Tsurf and Tair
are in Kelvin.
Rni - |
isothermal net radiation (W m-2) |
Jones, H. 2014: Plants and Microclimate. 3rd edition, Cambridge University Press.
# calculate isothermal net radiation of a surface that is 2degC warmer than the air.
isothermal.Rn(Rn=400,Tair=25,Tsurf=27,emissivity=0.98)