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apps:biomet_utci [2015/03/31 23:40] – enviadmin | apps:biomet_utci [2015/12/22 22:29] – enviadmin | ||
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* Wind Speed: UTCI as used in the software is limited to a wind speed range of 0.5 to 17 m/s related to 10 m Height | * Wind Speed: UTCI as used in the software is limited to a wind speed range of 0.5 to 17 m/s related to 10 m Height | ||
* Height reference: UTCI always related to wind speed at 10 m height while the biometeorological parameters are normally define between 1.5 and 2 m... | * Height reference: UTCI always related to wind speed at 10 m height while the biometeorological parameters are normally define between 1.5 and 2 m... | ||
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+ | As the UTCI calculation expects the wind given at the 10 m level, ENVI-met BioMet uses the calculated local wind speed $Wind_{zlevel}$ in the model domain related to the pedestrian level ($zlevel$) and scales it up to the 10 m level equivalent using the logarithmic wind power profile | ||
+ | $$ Wind_{10m} = \frac{ln(10 / z0)}{ln(zlevel / z0)} \cdot Wind_{zlevel}$$ | ||
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+ | In other words, if you calculate UTCI at some point for zlevel= 1.6 m, all ENVI-met data such as air temperature or radiative temperature will be used from this level, except of the wind speed which will be extrapolated to the 10 m level value. | ||
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+ | Obviously, that doesn' | ||
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+ | ==== Final Remarks ==== | ||
+ | We do not recommend to use UTCI in the regression-based version based on using 2m (1.6m) level wind speeds extrapolated to 10m. In a complex urban environment, | ||
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**Please Note**: | **Please Note**: |