Temperature formulas (Heat Overlay)
Revision as of 13:58, 11 September 2019 by Frank@tygron.nl (talk | contribs) (→Wet-bulb Temperature formula)
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,
- Ta,t is the calculated atmospheric temperature at time t;
- Tstation,t is the temperature measured at a weather station at time t;
- UHImax,t is the calculated Urban Heat Island effect at time t;
- fsun,t is the sun daily motion factor at time t;
Wet-bulb Temperature formula
Tw = Ta * atan( 0.151977 * (ϕ + 8.313659)0.5) + atan (Ta + ϕ) - atan(ϕ - 1.676331) + 0.00391838*ϕ3/2 atan(0.023101ϕ) - 4.686935