2. Meteorological Institute Faculty of Forest and Environmental Sciences gerd.jendritzky@meteo.uni-freiburg.de The Universal Thermal Climate Index UTCI Goal and State of COST Action 730 and ISB Commission 6 Gerd Jendritzky1, George Havenith2, Philipp Weihs3, Ekaterina Batchvarova4, and Richard DeDear5 1Meteorological Institute, Univ of Freiburg, Germany 2Loughborough Univ, Loughborough, U.K. 3Univ Soil Culture, Vienna, Austria 4Nat. Inst. Meteorology Hydrology, Sofia, Bulgaria 5Dept. Physical Geography, Macquarie Univ, Sidney, Australia

3. Meteorological Institute Faculty of Forest and Environmental Sciences gerd.jendritzky@meteo.uni-freiburg.de conduction convection respiration Sweat evaporation clothing Direct radiation Sun or other radiation source Reflected radiation Infra-red radiation infra-red radiation M External work Avenues of Heat Exchange (G. Havenith, 2001)

4. Meteorological Institute Faculty of Forest and Environmental Sciences gerd.jendritzky@meteo.uni-freiburg.de The human heat budget M + W + Q* + Q H + Q L + Q SW + Q Re + S = 0 MMetabolic rate WMechanical power Q*Radiation budget (Tmrt) Q H Turbulent flux of sensible heat (Ta,v) Q L Turbulent flux of latent heat (diffusion water vapour) (vp,v) Q SW Turbulent flux of latent heat (sweat evaporation) (vp,v) Q Re Respiratory heat flux (sensible and latent) (Ta,vp) SStorage

5. Meteorological Institute Faculty of Forest and Environmental Sciences gerd.jendritzky@meteo.uni-freiburg.de Why UTCI? Simple thermal indices do not consider sufficiently: (1) heat exchange theory (2) thermo-physiology Thus simple thermal indices show inacceptable shortcomings Last 35-40 years: Heat budget modelling Need: Dose-response related procedure Integration of new knowledge and concerns Need: Harmonization  UTCI (ISB, COST, WMO, ISO)

6. Meteorological Institute Faculty of Forest and Environmental Sciences gerd.jendritzky@meteo.uni-freiburg.de Main objective of joint activities of ISB Comm. 6 and COST Action 730 on UTCI: to develop and make easily available a physiologically assessment model of the thermal environment based on one of the “most advanced thermo-physiological models” in order to significantly enhance applications related to health and well-being in the fields of: public weather service public health system precautionary planning climate impact research > 40 scientists from 22 countries (Europe, IL, CA, AUS, NZ)

7. Meteorological Institute Faculty of Forest and Environmental Sciences gerd.jendritzky@meteo.uni-freiburg.de The UTCI model weather data Tmrt v vp Ta Single index UTCI

8. Meteorological Institute Faculty of Forest and Environmental Sciences gerd.jendritzky@meteo.uni-freiburg.de The UTCI model weather data Tmrt v vp Ta Multi-node Thermo- physiogical Model Single index UTCI

9. Meteorological Institute Faculty of Forest and Environmental Sciences gerd.jendritzky@meteo.uni-freiburg.de Fiala et al. 2001 Principle of Fiala‘s 340 node model

10. Meteorological Institute Faculty of Forest and Environmental Sciences gerd.jendritzky@meteo.uni-freiburg.de The UTCI model weather data Tmrt v vp Ta Multi-node Thermo- physiogical Model + Clothing Model Single index UTCI

11. Meteorological Institute Faculty of Forest and Environmental Sciences gerd.jendritzky@meteo.uni-freiburg.de Ta °C

12. T core T skin Skin Blood Flow Sweating Shivering Brain Controllers Behaviour Skin Temperature Threshold + - Core Temperature Threshold + - Environment Heat Exchange Heat Exchange Havenith, 2001 Human Physiology Model Control System

13. Meteorological Institute Faculty of Forest and Environmental Sciences gerd.jendritzky@meteo.uni-freiburg.de The UTCI model weather data Tmrt v vp Ta Multi-node Thermo- physiogical Model + Clothing Model T core, local T skin, skin wettedness thermal sensation, etc. Single index UTCI Average human response

14. Meteorological Institute Faculty of Forest and Environmental Sciences gerd.jendritzky@meteo.uni-freiburg.de 1 Rectal temperature 2 Mean skin temperature 3 Face skin temperature 4 Skin blood flow 5 Skin wettedness 6 Sweating 7 Shivering Model response in Reference Conditions Ta °C +50 -50 0 75.000 simulations Fiala 340 node model

15. Meteorological Institute Faculty of Forest and Environmental Sciences gerd.jendritzky@meteo.uni-freiburg.de Global Ta / vp distribution 65535 random samle out of 747.520.000 data (0,00877%); ECHAM4/T106 Ctrl TT 47,42 °C max -74,60 °C min vp 40,19 hPa max 0,03 hPa min TD 28,96 °C max -76,89 °C min

16. Meteorological Institute Faculty of Forest and Environmental Sciences gerd.jendritzky@meteo.uni-freiburg.de Summary: Basic features of UTCI Thermo-physiologically significant in the whole range of heat exchange conditions Valid in all climates, seasons and scales Independent of individual characteristics Prediction of whole body and local (WCI) thermal effects Based on the advanced 340-node model (Fiala) Met input data: Ta, v, vp, Tmrt Temperature scale index Reference conditions: Walking 4km/h (2,3 met), Tmrt = Ta, v(10m) = 0,5 m/s, RH = 50%, levelled off at vp = 20 hPa Fast calculation procedure for operational use International standard for human biometeorological core applications (WMO-Guideline, ISO(?))

17. Meteorological Institute Faculty of Forest and Environmental Sciences gerd.jendritzky@meteo.uni-freiburg.de