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vapor_pres_rh

Compute vapor pressure given relative humidity (%) and saturation vapor pressure.

Prototype

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"  ; This library is automatically loaded
                                                             ; from NCL V6.2.0 onward.
                                                             ; No need for user to explicitly load.

	function vapor_pres_rh (
		rh    : numeric,  
		esat  : numeric   
	)

	return_val [dimsizes(rh)] :  numeric

Arguments

rh

A scalar or multi-dimensional array of relative humidity (%)

esat

A scalar or multi-dimensional array of saturation vapor pressure. Must conform to rh. p.

Return value

The returned vapor pressurevalue(s) will have the same shape and size as rh. It will be type double if any of the input arguments is type double; otherwise the values will by type float.

Description

Simple formula:


      e = (rh/100)*esat

See Also

wetbulb, dewtemp_trh, relhum, relhum_ttd

Examples

Example 1: Compute vapor pressure.

   rh = 80        ; %
   es = 2000      ; Pa
   es@units = "Pa"

   vp = vapor_pres_rh(rh, es)
   print(vp)
The output is:

    Variable: vp
    Type: float
    Total Size: 4 bytes
                1 values
    Number of Dimensions: 1
    Dimensions and sizes:	[1]
    Coordinates: 
    Number Of Attributes: 2
      long_name :	Vapor Pressure
      units :           Pa
      NCL :	vapor_pres_rh
    (0)	1600