Temperature formulas (Heat Overlay): Difference between revisions

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where,
where,
* T<sub>a,t</sub> is the calculated [[Temperature_atmosphere_result_type_(Heat_Overlay)|atmospheric temperature]] at time t;
* T<sub>a,t</sub> is the calculated [[Temperature_atmosphere_result_type_(Heat_Overlay)|atmospheric temperature]] at time t;
* T<sub>station,t</sub> is the temperature measured at a weather station at time t;
* T<sub>station,t</sub> is the [[Hourly_temperature_(Heat_Overlay)|temperature]] measured at a weather station at time t;
* UHI<sub>max,t</sub> is the calculated [[UHI_formula_(Heat_Overlay)|Urban Heat Island]] effect at time t;
* UHI<sub>max,t</sub> is the calculated [[UHI_formula_(Heat_Overlay)|Urban Heat Island]] effect at time t;
* f<sub>sun,t</sub> is the [[Sun_daily_motion_(Heat_Overlay)|sun daily motion factor]] at time t;
* f<sub>sun,t</sub> is the [[Sun_daily_motion_(Heat_Overlay)|sun daily motion factor]] at time t;

Revision as of 14:31, 11 September 2019

Two temperature formulas are used in the calculation of the PET value:

  • The atmospheric temperature Ta
  • The wet-bulb temperatur Tw

Atmospheric Temperature formula

Ta,t = Tstation,t + UHImax,t * fsun,t
where,

Wet-bulb Temperature formula

Tw = Ta * atan( 0.151977 * (ϕ + 8.313659)0.5) + atan (Ta + ϕ) - atan(ϕ - 1.676331) + 0.00391838ϕ3/2 atan(0.023101ϕ) - 4.686935

See also