The Thermal Environment of the Human Being - A subjective retrospection on methodologies -

1. The Thermal Environment of the Human Being- A subjective retrospection on methodologies - Gerd Jendritzky1 and George Havenith2 1Meteorological Institute, University of Freiburg, Germany 2Environmental Ergonomics Research Centre, Loughborough University, U.K. gerd.jendritzky@meteo.uni-freiburg.de g.havenith@lboro.ac.uk

2. Overview • Applications (selected examples) • Basics in heat exchange • Simple Climate Indices • Heat Balance Models • The Future: Incorporating the Human • Provocative remarks

3. Why? • Assessment of the thermal environment: Key issue in human biometeorology!

4. Applications • Public weather service • Public health system • Precautionary planning • Climate impact research

5. Human Biometeorology Modelled Heat Load and Observed Mortality 2003, Baden-Württemberg christina.koppe@dwd.de DWD 2004

6. Heat related extra deaths in Europe, August 2003 heat load extreme • 2045 strong • 1400 • 7000 moderate • 150 slight comfortable slight moderate strong • 14805 extreme cold stress UTC 13:00 • 4230 • 4175

7. Human Biometeorology Paris (1991 - 1998) 150 140 London (1976 - 2000) 130 SW Germany (1968 - 2003) 150 150 Lisbon (1981 - 1998) 120 140 Budapest (1972 - 2001) 150 Lisbon (1981 - 1998) 140 110 150 130 400 140 130 Mortality 100 140 350 120 130 90 120 300 130 110 F(%) = 0 1 28 46 15 9 1 0 120 Mortality (%) 110 -3 -2 -1 0 1 2 3 4 250 120 100 Mortality (%) 110 200 100 Thermal stress category Mortality (%) 90 110 100 Mortality (%) 90 150 F(%) = 0 0 27 55 13 4 0 0 Mortality (%) 100 F(%) = 0 1 27 40 18 12 1 0 -3 -2 -1 0 1 2 3 4 90 100 -3 -2 -1 0 1 2 3 4 90 F(%) = 0 0 5 48 28 17 2 0 50 Thermal stress category F(%) = 0 3 31 33 18 13 2 0 -3 -2 -1 0 1 2 3 4 F(%) = 0 0 5 48 28 17 2 0 Thermal stress category -3 -2 -1 0 1 2 3 4 -3 -2 -1 0 1 2 3 4 Thermal stress category Thermal stress category Thermal stress category Mortality by Thermal Stress (Koppe, 2004)

8. U PT 42 °C TMRT 38 height 34 T air 30 26 width gerd.jendritzky@meteo.uni-freiburg.de

9. Business Unit Human Biometeorology Berlin frequency of heat load angelika.graetz@dwd.de

10. .10 1961-1990 (obs) .08 2003 .06 Frequency .04 1961-1990 (mod) 2071-2100 .02 0 5 10 15 20 25 30 35 40 45 50 Average summer Tmax [°C] Beniston, 2004 The heat wave 2003 in Europe: A unique feature? IPCC WGI, 2001: “Higher maximum temperatures and more hot days over nearly all land areas are very likely”  Need to adapt

11. July Delta Perceived Temperature (K), (IS92a-CTL) data: Deutsches Klimarechenzentrum Hamburg; ECHAM4/T106 birger.tinz@dwd.de

12. Body Core Temperature cold warm

13. Heat Balance Heat Production Heat Loss

14. The human heat budget M + W + Q* + QH + QL + QSW + QRe + S = 0 M Metabolic rate W Mechanical power Q* Radiation budget (Tmrt,v) QH Turbulent flux of sensible heat (Ta,v) QL Turbulent flux of latent heat (diffusion water vapour) (e,v) QSW Turbulent flux of latent heat (sweat evaporation) (e,v) QRe Respiratory heat flux (sensible and latent) (Ta,e) S Storage

15. Simple (mostly two-parameter) thermal indices, „comfort indices“ (> 100 known) Examples: Air temperature Ta Heat index (Ta, RH) Windchill Index (Ta, v) WBGT I Assessment Procedures

16. Principle Each value of an index must result in the same thermophysiologial effect, regardless of the combinations the meteorological and other environmental input values. No simple index is able to fulfill this requirement!

17. Weather classifications (holistic approach) (e.g. Kalkstein et al.) Successful in health studies Successful in HHWSs II Assessment Procedures

18. Sun or other radiation source Sweat evaporation respiration Direct radiation Infra-red radiation clothing M convection External work Reflected radiation infra-red radiation conduction Avenues of Heat Exchange Havenith, 2003

19. Heat balance model Assessment Procedures Simple index

20. The Comfort Equation Fanger, 1970

22. Problems • Heat balance models assume “steady state” condition of the human body • Models only consider two nodes (core and shell) • Physiological response is simplified

23. Physiological reaction to body cooling Havenith, 2005

24. Skin Temperature Havenith/ Adidas, 2004

25. Heat balance model Human Physiology model Future Expansion Simple index

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

27. Fiala et al., 2001

28. Future Expansion Simple index Heat balance model Human Physiology model European COST Action 730: Universal Thermal Climate Index (UTCI)

29. Action 730 on UTCI Fiala et al. 2001

30. Final Provocative Remarks • Temperature related mortality: People die from heat load! • Holistic approaches: For what when we basicly know the physiological link! • Simple thermal indices: - Former times: Lack of knowledge - Later : No access to computer facilities - Since years : Ignorance of physiological basics • Complete heat budget models state-of-the-art • Future: Human response related improved models  UTCI • Shouldn‘t scientific journals reject manuscripts not based on state-of-the-art?