Compute net radiation as the difference between net shortwave and net longwave radiation.
Available in version 6.4.0 and later.
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/crop.ncl" ; This library is automatically loaded ; from NCL V6.5.0 onward. ; No need for user to explicitly load. function netrad_fao56 ( netsw : numeric, netlw : numeric )
Net shortwave radiation as derived from FAO 56 EQN 38.netlw
Net longwave radiation as derived from FAO 56 EQN 39. Same units, size, shape and type as netsw.
An array with the same dimensionality and type as netsw containing the desired quantity.
Here, this is simply:
netrad = netsw - netlwAll appropriate metadata are returned.
Example 1: Example 12, Chapter 3 of FAO-56.
rsol = 14.5 ; solar radiation; MJ/(m2-day) [ Example 10] rsw_net = (1-0.23)*rsol ; net solar; 11.1 [ EQN 38] rlw_net = 3.5 ; long wave radiation MJ/(m2-day) [ Example 11 ] rnet = netrad_fao56(rsw_net, rlw_net) printVarSummary(rnet)
The edited output is:
Variable: rnet Type: float Total Size: 48 bytes 12 values Number of Dimensions: 1 Dimensions and sizes:  Coordinates: Number Of Attributes: 3 _FillValue : 9.96921e+36 long_name : net radiation units : MJ/(m2-day) (0) 7.6