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heat_wbgt_simplified

Simplified WBGT index.

Available in version 6.4.0 and later.

Prototype

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/heat_stress.ncl"  ; This library is automatically loaded
                                                             ; from NCL V6.5.0 onward.
                                                             ; No need for user to explicitly load.

	function heat_wbgt_simplified (
		t          : numeric,  
		vp         : numeric,  
		iounit [2] : integer,  
		opt    [1] : logical   
	)

	return_val [dimsizes(t)] :  float or double

Arguments

t

Scalar or array containing temperature(s) [ units see iounit(0) ].

vp

Scalar or array containing vapor pressure (Pa).

iounit

An integer array of length 2 which specifies the units of the input t and vp:

  • iounit(0)=0 input t (degC)
  • iounit(0)=1 input t (degK)
  • iounit(0)=2 input t (Farenheit)

  • iounit(1)=0 input vp (hPa)
  • iounit(1)=1 input vp (Pa)
  • iounit(1)=2 input vp (kPa)

opt

Currently not used. Set to False.

Return value

A scalar or an array of the same size and shape as t. The output will be double if t or rh is of type double. This is a unitless quantity.

Description


 REFERENCES: 
    Willett, K.M., and S. Sherwood, 2010: 
            Exceedance of heat index thresholds for 15 regions under a warming 
               climate using the wet-bulb globe temperature,
            Int. J. Climatol.  doi:10.1002/joc.2257

    Buzan, J.R. et al (2015): 
           Implementation and comparison of a suite of heat stress metrics
              within the Community Land Model version 4.5
           Geosci. Model Dev., 8, 151–170, 2015
           www.geosci-model-dev.net/8/151/2015/    doi:10.5194/gmd-8-151-2015

See Also

Heat and Stress functions

Examples

Example 1: 

   ta     = 25.0             ; C
   vp     = 150.             ; Pa
   iou    = (/0, 1/)         ; C, Pa

   wbgt_s = heat_wbgt_simplified(ta, vp, iou, 0)
   print(wbgt_s)
The output is: 
    Variable: wbgt_s
    Type: float
    Total Size: 4 bytes
                1 values
    Number of Dimensions: 1
    Dimensions and sizes:	[1]
    Coordinates: 
    Number Of Attributes: 2
      long_name :	simplified wet-bulb index
      NCL :	heat_wbgt_simplified

    (0)	18.7045