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Heat stress
heat_apptemp
Compute apparent temperature.
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_apptemp ( t : numeric, vp : numeric, w10 : numeric, iounit [3] : integer, opt : integer ) return_val [dimsizes(t)] : float or double
Arguments
tScalar or array containing temperature(s) [ units see iounit ].
vpScalar or array containing vapor pressure (Pa).
w10Scalar or array containing 10-meter winds (m/s).
iounitAn integer array of length 2 which specifies the units of the input t and returned heat_index:
- 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)
- iounit(2)=0 returns units degC
- iounit(2)=1 returns units degK
- iounit(2)=2 returns units Farenheit
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. The units are specified by iounit(1).
Description
Wikipedia: Apparent temperature is the general term for the perceived outdoor temperature, caused by the combined effects of air temperature, relative humidity and wind speed.
REFERENCES: Australian Bureau of Meteorology http://www.bom.gov.au/info/thermal_stress/#atapproximation Steadman, R.G., 1994: Norms of apparent temperature in Australia, Aust. Met. Mag., 43, 1-16. 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
Examples
Example 1:
t = 30.5 ; C vp = 20.0 ; Pa w10 = 10.0 ; m/s at = heat_apptemp(t, vp, w10, (/0,1,0/), 0) print(at)The output is:
Variable: at Type: float Total Size: 4 bytes 1 values Number of Dimensions: 1 Dimensions and sizes: [1] Coordinates: Number Of Attributes: 5 long_name : apparent temperature units : degC reference_1 : Steadman, R.G., 1994: Norms of apparent temperature in Australia, Aust. Met. Mag., 43, 1-16 reference_2 : Buzan et al (2015): eq (1) NCL : heat_apptemp (0) 19.566