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netrad_fao56

Compute net radiation as the difference between net shortwave and net longwave radiation.

Available in version 6.4.0 and later.

Prototype

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   
	)

Arguments

netsw

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.

Return value

An array with the same dimensionality and type as netsw containing the desired quantity.

Description

Here, this is simply: 

    netrad = netsw - netlw
All appropriate metadata are returned.

See Also

Crop & Evapotranspiration functions

Examples

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:	[1]
Coordinates: 
Number Of Attributes: 3
  _FillValue :	9.96921e+36
  long_name :	net radiation
  units :	MJ/(m2-day)

(0)  7.6