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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:
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
```

## 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

```