AEM LAMBECHT METEO 00.95800.010000, Руководство пользователя

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12.4.5. Annex – formula wind chill
The wind chill (Twc) is calculated as follows:
Twc = 13.12 + 0.6215 · T - 11.37 · Vw^(0.16) + 0.3965 · T · Vw^(0.16)
Thereby:
Twc = Wind chill-temperature (in °C)
T = real temperature (in °C)
Vw = Wind speed in km/h
The wind speed should be between 4.8 and 177 km/h (1.3 m/s to 50 m/s).
The temperature should be between –50 and 10 °C.
(This new formula is used from the NOAA since the 01.11.2011).
12.4.6. Annex – formula dew point
The dew point (DT) is calculated as follows:
DT = c3·ln(0,01·RH·SVP(TT)/c1)/(c2-ln(0,01·RH·SVP(TT)/c1))
Thereby
DT = Dew point temperature in °C
RH = relative humidity in %
SVP(TT) = Saturation vapour pressure in mbar over water at the air temperature TT in °C
SVP(TT) = c1*e^(c2*TT/(c3+TT))
TT = Air temperature in °C
ln() = Natural logarithm
Inserted in DT results:
DT= c3·ln(0,01·RH·c1·e^(c2·TT/(c3+TT))/c1)/(c2-ln(0,01·RH·c1·e^(c2·TT/(c3+TT))/c1))
The constants c1, c2, c3 depend on the temperature TT
Temperature in °C c1 c2 c3
- 50,9 ≤ TT < 0,0 6,10780 17,84362 245,425
0,0 ≤ TT ≤ 100,9 6,10780 17,08085 234,175