Net longwave radiation (Rnl).
Rnl(
x,
Tmax = NULL,
Tmin = NULL,
Rhmax = NULL,
Rhmin = NULL,
Rs = NULL,
lat.rad = NULL,
lat.deg = NULL,
long.deg = NULL,
elev,
actVP = NULL,
tl,
Tmean = NULL,
Rhmean = NULL,
control = list()
)date-time object or day of the year (must be date-time object if calculation period is shorter than a day)
maximum temperature [degreeC] during 24-hour period (for daily values)
minimum temperature [degreeC] during 24-hour period (for daily values)
daily maximum of air humidity [percent] (for daily values)
daily minimum of air humidity [percent] (for daily values)
incoming solar radiation [MJ/(m2 time)]
latitude [rad]. Use either lat.rad or lat.deg. Latitude is positive for the northern hemisphere and negative for the southern hemisphere
latitude [degree]. Use either lat.deg or lat.rad. Latitude is positive for the northern hemisphere and negative for the southern hemisphere
see Rso
station elevation above sea level [m]
Actual vapor pressure [kPa]. If Rhmax, Rhmin and Rhmean are NULL
length of calculation period [hour] (1 for hourly period, 0.5 for a 30-minute period or 24 for daily period). Only needed if length of x is date-time object with length of 1.
mean temperature [degreeC] during the time period (for periods shorter than a day)
Mean air humidity [percent] (for periods shorter than a day or if Rhmax and Rhmin are missing)
list for control parameters and empirical factors (see Details and controlDefaults)
Rnl net outgoing longwave radiation [MJ(/m2 time)]
Allen, R. G., Pereira, L. S., Raes, D., & Smith, M. (1998). Crop evapotranspiration-Guidelines for computing crop water requirements-FAO Irrigation and drainage paper 56. FAO, Rome, 300(9).