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heat_thic_thip

Compute the thermal humidity comfort index (thic) and the thermal humidity physiology index (thip).

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_thic_thip (
		t          : numeric,  
		twb        : numeric,  
		iounit [1] : integer,  
		opt        : integer   
	)

	return_val [variable of type list containing two variables wuth the same dimensionality as t] :  float or double

Arguments

t

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

twb

Scalar or array containing wet bulb temperature [ units must match t ].

opt

Currently not used. Set to 0.

Return value

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

Description

Quantified estimates for Comfort (THIC) and Physiology (THIP)

   THIC:
     75-78: alert
     79-83: dangerous
     84+  : very dangerous

REFERENCES: 

    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:

   t   = 30.25      ; C
   twb = 25.5       ; C

   ThicThip = heat_thic_thip(t, twb, 0, 0)
   thic     = ThicThip[0]        ; extract 'thic' from list variable; convenience only 
   thip     = ThicThip[1]        ; extract 'thip' 
   delete(ThicThip)                  ; no longer needed

   print(thic)
   print(thip)

The output is
    Variable: thic
    Type: float
    Total Size: 4 bytes
                1 values
    Number of Dimensions: 1
    Dimensions and sizes:	[1]
    Coordinates: 
    Number Of Attributes: 2
      long_name :	Temperature Humidity Index Comfort: Livestock
      units :	
    (0)	80.74
    
    
    Variable: thip
    Type: float
    Total Size: 4 bytes
                1 values
    Number of Dimensions: 1
    Dimensions and sizes:	[1]
    Coordinates: 
    Number Of Attributes: 2
      long_name :	Temperature Humidity Index Physiology
      units :	
    (0)	83.4575