1. Human Comfort in the Urban Environment

2. The Human Response to Climate Physical environment is the single most important determination of human actions and activities- environmental determinism Climate is a major component of the environment, gave rise to climate determinism

3. Solar loading impact on human thermal comfort M + Qn + C – LE = 0

4. Physiological responses Human body temperature is around 98.6F (37C) balanced by body’s heat loss and heat gain. Loss: radiation, conduction, evaporation of moisture from the skin surface Gain: absorption of long- wave and short-wave radiation, conduction from the surrounding air

5. http://www.shapesense.com/fitness- exercise/calculators/resting-metabolic-rate- calculator.aspx Metabolic Rates for various activities The metabolic rate, or human body heat or power production, is often measured in the unit "Met". The metabolic rate of a relaxed seated person is one (1) Met, where 1 Met = 58 W/m 2 (356 Btu/hr) The mean surface area, the Du-Bois area, of the human body is approximately 1.8 m 2 (19.4 ft 2 ). The total metabolic heat for a mean body can be calculated by multiplying with the area. The total heat from a relaxed seated person with mean surface area would be 58 W/m 2 x 1.8 m 2 = 104 W (356 Btu/hr) ActivityW/m 2 W 1) Btu /hr 1) Met Reclining Sleepimng 46832820.8 Seated relaxed 581043561.0 Standing at rest 701264301.2 Sedentary activity (office, dwelling, school, laboratory ) school 701264301.2 Car driving 801444911.4 Graphic profession - Book Binder 851535221.5 S tanding, light activity (shopping, laboratory, light industry) 931675711.6 Teacher 951715831.6 Domestic work -shaving, washing and dressing 1001806141.7 Walking on the level, 2 km/h 110198675 1.9 Running 8-9

6. Activity Human Metabolic Rate (W/m 2 )(Met)Met Laying down460.8 Sitting, relaxed581.0 Standing, relaxed701.2 Sitting activity (office work, school etc.) 701.2 Standing activity (shop, laboratory etc.) 931.6 Moving activity (house work, working at machines etc.) 1162.0 Harder activity (hard work at machines, work shops etc. ) 1652.8

7. Effort LevelTypical Tasks Heart Rate Elevation (beats per minute) Body Energy Expenditur e (watts) Work Duration Restriction (hours) Light riding bicycle at 10 km/h, canning paint, raking leaves, making drawings, machining light objects, sewing by hand 0 - 3570 - 175none Moderate building brick wall, cleaning boiler, planing softwood, sheet-metal working, soldering, using screwdrivers, walking on level 35 - 55175 - 260> 2 Heavy digging trenches, using sledge- hammer, stoking furnace, metal grinding, walking up 5% gradient 55 - 75260 - 420< 1 to 2 Very Heavy shoveling sand, using jackhammer, stacking concrete blocks, stone masonry, climbing normal stairs 75 - 90420 - 700< 1 to 2 Extremely Heavy sawing wood, climbing vertical ladder > 90> 700 < 0.25 to 0.3 Heart rate, energy expenditure

8. The insulation of clothes are often measured in the unit "Clo", where 1 Clo = 0.155 m 2 K/W Clo = 0 - corresponds to a naked person Clo = 1 - corresponds to the insulating value of clothing needed to maintain a person in comfort sitting at rest in a room at 21 ℃ (70 ℉ ) with air movement of 0.1 m/s and humidity less than 50% - typically a person wearing a business suit http://www.engineeringtoolbox.com/clo-clothing-thermal-insulation- d_732.html http://www.engineeringtoolbox.com/metabolism-clothing-activity- d_117.html Clothing and human comfort

9. Basic concepts Radiation Wavelength, frequency Shortwave radiation: solar radiation composed of Ultraviolet radiation ( 0.7um) Longwave radiation: earth’s radiation.

10. Wien’s law: 2897/T (in Kelvin); the higher the air temperature the shorter the wave length radiated Relationship between air temperature and wavelength

11. Impact of radiation on people UV-C: most damage, absorbed by ozone in stratosphere UV-B and UV-A arrives the earth’s surface Radiation determines the effects of thermoregulation and photochemical responses that occur in the skin (1)Production of vitamin D, necessary for the prevention of bone disease (2)Sunburn, red and blistering (dilating chemical), may lead to aging and skin cancer Table 7.4;7.5)

12. (3) Seasonal affective disorder (SAD): mood disturbances related to season (related to too much or too little solar radiation). Example: winter depression. Sadness, decreased physical activity, weight gain, decreases libido, interpersonal conflict. (light therapy or drug)

13. Basic concepts (continue) Conduction: energy transfer directly from molecule to molecule by contact one another Convection: energy transfer by mixing of molecules with different temperature Evaporation Latent heat (LE): energy stored in water by changes in phase Sensible heat (H): energy transfer is measured (reflected) in temperature change. Net radiation (Q)=LE+H

14. Human responses to extreme temperatures

15. Maximum recommended work load TemperatureRelative Humidity (%) oFoF oCoC30406080 27Very Heavy Heavy 9032Very HeavyHeavyModerateLight 10038HeavyModerateLight Not recommen ded 11043ModerateLight Not recommen ded 12049Light Not recommen ded Heat Discomfort Zone

16. Water vapor Dew point temperature: temperature to which a parcel of air cools to condensation Saturation: air is holding the maximum moisture at the give air temperature (Fig 4.6) Holding capacity increases dramatically at higher air temperature Vapor pressure: the weight of vapor over a unit surface Relative humidity: (vapor- pressure-in-air/saturation- vapor-pressure)*100% How close the air to saturation

17. Biometeorological Indices Serve to predict various responses to the sensation of warmth and to assess the physiological strain imposed by combined atmospheric variables 2 most common indexes for heat are: (1)Apparent temperature (AT) (2)Heat stress Index (HI) Signs of heat stroke: (a)Cessation of perspiration cooling mechanisms (b)Raising body T near 110F (c)Skin becomes dry and hot pulse become rapid and irregular

18. Heat Index in degrees Fahrenheit The heat index can be calculated as t HI = -42.379 + 2.04901523 t + 10.14333127 φ - 0.22475541 t φ - 0.00683783 t 2 - 0.05481717 φ 2 + 0.00122874 t 2 φ + 0.00085282 t φ 2 - 0.00000199 (T φ) 2 (1) where t HI = heat index ( o F) t = air temperature ( o F) (t > 57 o F) φ = relative humidity (%) Caution - Fatigue is possible with prolonged exposure and/or physical activity 2) Extreme Caution - Sunstroke, heat cramps and heat exhaustion are possible with prolonged exposure and/or physical activity 3) Danger - Sunstroke, heat cramps and heat exhaustion are likely. Heat stroke is possible with prolonged exposure and/or physical activity 4) Extreme Danger - Heatstroke/sunstroke is highly likely with continued exposure

19. Heat Index Table Figure 2

20. "Chilled" Air Temperature ( o F) Ambient Air Temper ature ( o F) Wind Velocity (mph) 510152025303540 363432302928 27 35312725242321 20 30252119171614 13 25191513119776 2013964300 15730-2-4-7 -8 101-4-7-9-11-14 -15 5-5-10-13-15-17-21 -22 0-11-16-19-22-24-27 -29 -5-16-22-26-29-31-37-34-36 -10-22-28-32-35-37-41 -43 -15-28-35-39-42-44-48 -50 -20-34-41-45-48-51-55 -57 -25-40-47-51-55-58-62 -64 -30-46-53-58-61-64-69 -71 -35-52-59-64-68-71-76 -78 -40-57-66-71-74-78-82 -84 Wind Chill Index - Wind Velocity mph and degrees Fahrenheit The "Chilled" air temperature can also be expressed as a function of wind velocity and ambient air temperature as t wF = 35.74 + 0.6215 t a - 35.75 v 0.16 + 0.4275 t a v 0.16 (2)

21. "Chilled" Air Temperature ( o C) Ambient Air Tempera ture ( o C) Wind Velocity (km/h) 510152030405060 10 9877655 543210 -2 0 -3-4-5-6-7-8-9 -5-7-9-11-12-13-14-15-16 -10-13-15-17-18-20-21-22-23 -15-19-21-23-24-26-27-29-30 -20-24-27-29-30-33-34-35-36 -25-30-33-35-37-39-41-42-43 -30-36-39-41-43-46-48-49-50 -35-41-45-48-49-52-54-56-57 -40-47-51-54-56-59-61-63-64 Wind Chill Index - Wind Velocity km/h and degrees Celsius The "Chilled" air temperature can also be expressed as a function of wind velocity and ambient air temperature as t wC = 13.12 + 0.6215 t a - 11.37 v 0.16 + 0.3965 t a v 0.16 (1) where t wC = effective "wind" temperature ( o C) t a = air temperature ( o C); v = wind velocity (km/h)

22. Low Temperature impact: Windchill index (To predict frost bite) Windchill: coined by Antarctic explorer Paul A Siple to describe the cooling power of wind for various combinations of temperatures and wind speed Measurement: First in Antarctic to measure the rate of freezing of water at various temperature and wind speed Then modified windchill formula to include the effect of clothing variables of breathing and heat transfer through clothing Model assumptions: a healthy adult (1.7m height, body surface area 1.7m 2 ) walking outdoors at 1.33 m/s will to generate 188wm -2 of heat To main thermal equilibrium, amount of heat loss must not exceed the amount of heat generated. The balance is achieved by wearing an appropriate thickness of clothing Windchill advisories are based on the sensation of cold felt by the majority of people

23. Windchill index

24. Wind Chill Table Figure 1

25. How We Lose Heat to the Environment Hypothermia 1. Hypothermia - "a decrease in the core body temperature to a level at which normal muscular and cerebral functions are impaired." - Medicine for Mountaineering 2. Conditions Leading to Hypothermia Cold temperatures Improper clothing and equipment Wetness Fatigue, exhaustion Dehydration Poor food intake No knowledge of hypothermia Alcohol intake - causes vasodilation leading to increased heat loss

26. Climate and Health Climatotherapy: the utilization of prevailing climate as therapeutic “escape weather”-travel for climate (Summer palaces, Mediterranean yachts, Florida homes) Intense heat stresses circulatory system; Cold, damp weather cause depression and circulatory problems Diseases of respiratory system are worsened in places with high airborne particle counts (asthma, bronchitis, tuberculosis).

27. Morbidity and Mortality Incidence of asthma increases markedly with onset of cold weather; respiratory disease occur much more in winter than in the summer (older and very young people are more vulnerable)

28. Heatwave and mortality

29. This graph tracks maximum temperature (Tmax), heat index (HI), and heat-related deaths in Chicago each day from July 11 to 23, 1995. The gray line shows maximum daily temperature, the blue line shows the heat index, and the bars indicate number of deaths for the day.

30. Impact of other extreme weather events on human health Direct impacts: injury and death by storms, flooding, etc Secondary impact: changes in ecosystem (bacteria, fungus etc); in public health infrastructure (availability of safe drinking water); mental problems (post traumatic disorder)

31. Stratospheric Ozone and UV radiation Decreases in ozone in stratosphere(5-10 miles above surface) lead to increases in UV radiation on troposhere During the 1980s and 1990s at northern mid-latitudes (such as Europe), the average year-round ozone concentration declined by around 4% per decade: over the southern regions of Australia, New Zealand, Argentina and South Africa, the figure approximated 6-7%. (ozone hole was detected during southern hemispheric spring over the Antarctic) The groups most vulnerable to skin cancer are white Caucasians, especially those of Celtic descent living in areas of high ambient UV. Culturally-based behavioral changes have led to much higher UV exposure, through sun-bathing and skin-tanning. The marked increase in skin cancers in western populations.

32. A more complete view of UV on human health

33. Indirect impacts: through infectious diseases 1. vector mosquitoes species that causes malaria, dengue and yellow fever (tropical and subtropical). 2. rodents act as reservoirs for various disease; flooding is associated with rodent-borne diseases. Other diseases associated with rodents and ticks thrive in temperate climate with wild winter. 3. Many diarrhoeal diseases vary seasonally, suggesting sensitivity to climate. In the tropics, it peaks during the rainy season. Both floods and droughts increase the risk of diarrhoeal diseases. Major causes of diarrhoea linked to heavy rainfall and contaminated water supplies. 4. food-borne infections (e.g. salmonellosis) peak in the warmer months 5. Climate affects air-pollution related diseases

34. Climate and Architecture Shelter with food is one of mainstays of human life on earth. The nature of shelter required largely depends on the conditions of the environment, climate is the most important Primitive people used the limited resources at hand developed shelters that were in harmony with the climatic conditions under which they lived.

35. How Cities Use Parks To Improve Human Health Parks provide people with contact with nature, known to confer certain health benefits and enhance well-being. Physical activity opportunities in parks help to increase fitness and reduce obesity. Parks resources can mitigate climate, air, and water pollution impacts on public health. Cities need to provide all types of parks, to provide their various citizen groups with a range of health benefits. Central Park, NY