Observing Climate. How do we measure climate parameters? Surface Measurements. - Temperature > Wind Chill Temperature Index > Heat Index.

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1 Observing Climate 3-1 How do we measure climate parameters? Surface Measurements - Temperature > Wind Chill Temperature Index > Heat Index - Pressure Observing - To see a world in a grain of sand, And a heaven in a wild flower, Hold infinity in the palm of your hand, And eternity in an hour. Auguries of Innocence by William Blake - Density - Water Vapor > Gas Laws - Wind - Clouds - Water - Precipitation Upper-air Measurements - Temperature, Pressure (Height), Water Vapor, Wind Remote Sensing Measurements

2 Observing Climate - Surface 3-2 Temperature Instrument Design Thermometers Maximum Temperature Minimum Temperature Thermograph Science Concepts Definition Kinetic Energy - Molecular Boiling Point Versus Altitude Expansion Surface Tension Exposure Temperature Scales Windchill Heat Index The Earth System (Kump, Kastin & Crane) Chap. 3 (pp ) Ventilation Radiational Heating Evaporational Cooling Temperature Versus Height Effect of Wind Effect of Humidity

3 3-3 Why do we need thermometers? Are we very good thermometers? What steps do we need to perform to build a thermometer?

3-4 Is there a problem here? Why do fevers give you the chills? When you have an infection, your body resets your internal thermostat above the normal 98.6 F, say to 101, 102 or maybe 103 F.

4 3-4 Is there a problem here? Why do fevers give you the chills? When you have an infection, your body resets your internal thermostat above the normal 98.6 F, say to 101, 102 or maybe 103 F. You then feel cold and shiver attempting to raise your body temperature to the new reset elevated level. When your fever breaks, your body sets your thermostat back to 98.6 F. That's when you start to sweat, throw off the covers. update.cfm?docid=251.

5 3-5 Definition Science quotes of 5th and 6th graders - Temperature is a measure of the average molecular kinetic energy of a substance As the temperature of most substances is increased, the substance expands Thermometer Galileo Galilei ( ) invented a thermoscope in 1593 A vibration is a motion that cannot make up its mind which way it wants to go. Took a sip of Pepsi. always iced it. Less heat. Less energy. Less motion in the molecules. Tony Hillerman, 1986: Skinwalkers, pp Galileo thermometer - Galileo discovered that liquid s density changes with temperature. Thus, fluid s buoyancy changes with temperature. Lowest floating sphere indicates room temperature. Italian Francesco Sagredo, a contemporary of Galileo s, divided the temperature scale into 360 divisions similar to the divisions in a circle; thus, the name degrees

6 3-6 Boiling Point of Water at Various Altitudes and Pressures Altitude Barometer Readings Boiling Point (feet) (mb) (in. Hg ) mm Hg F C

7 3-7 Temperature Scales Olef Roemer (Danish) and Isaac Newton (English) first to stress using two reference points to calibrate thermometers Newton used boiling and freezing points of water to calibrate his temperature scale. Roemer used the boiling point of water and the temperature of a mixture of ice, water and salt (colder than freezing) to calibrate his temperature scale, but designated 60 between the two points. Gabriel Fahrenheit (Dutch) developed mercury thermometer ( more accurate and could be divided into smaller divisions). In 1724, like Roemer, used temperature of a mixture of ice, water and salt as 0, but unlike Roemer, used human temperature as 96. Scale made explicitly for meteorology.

3-8 Thermometer Types Liquid-in-glass thermometer was invented about 1650 by the Grand Duke of Tuscany, Ferdinand II. Used spirits of wine as the liquid. - Mercury (Freezes at -38.

8 3-8 Thermometer Types Liquid-in-glass thermometer was invented about 1650 by the Grand Duke of Tuscany, Ferdinand II. Used spirits of wine as the liquid. - Mercury (Freezes at F) - Alcohol - Max-Min thermometer Read the Minimum side Second Liquid Note: bottom of the barbells Mercury Air Maximum side Note: Scales are reversed on the right and left sides of the thermometer

9 3-9 Thermometer Types (Con t) - Max-Min thermometer (Con t) > Belfort maximum-minimum thermometer - Model 6042 Maximum thermometer products/temphumid/m6042.html Mercury filled bulb tilted with bulb end 5 above horizontal Minimum thermometer Magnet used to reset metal barbell Alcohol filled bulb tilted with bulb end 5 below horizontal

3-10 Thermometer Types (Con t) Metallic expansion - Bimetallic strip > Furnace thermostat Brass Invar "Thermostat,"

11 3-11 Thermometer Types (Con t) Metallic expansion (Con t) - Bimetallic strip (Con t) > Thermograph Thies Clima Thermograph - Measures and records temperature

12 3-12 Thermometer Types (Con t) Metallic expansion (Con t) - Coiled bimetallic strip > Furnace thermostat Mercury Switch Bimetallic Coil Second Bimetalic Coil

3-13 Thermometer Types (Con t) Electric - Resistance Thermometer Exposure http://www.forestrysuppliers.com/product_pages/view_ Catalog_Page.

instrument shelter - Wood construction with 48 wood or metal legs. Painted white.

13 3-13 Thermometer Types (Con t) Electric - Resistance Thermometer Exposure Catalog_Page.asp?ID=5505 Shade Ventilation Dry Height - Shelter 4 ft above ground Location - Grassy area away from trees Forestry Suppliers cotton region instrument shelter - Wood construction with 48 wood or metal legs. Painted white. Louvered on all sides and vented through the bottom to provide ambient conditions inside while excluding radiation and precipitation. A double roof provides added protection against direct solar radiation.

3-14 Temperature Scales (Con t) Today's Fahrenheit (Daniel Gabriel 168

14 3-14 Temperature Scales (Con t) Today's Fahrenheit (Daniel Gabriel ) scale based on freezing point (32 ) and boiling point (212 ) of water. Human temperature is Swedish astronomer Anders Celsius ( ) revised a temperature scale using, like Newton, the freezing and boiling points of water as calibration points, but used 100 between the two points, i.e., the Centigrade scale. Celsius_eng.html

3-15 Temperature Scales (Con t) 1848 Lord Kelvin (William Thomson 1824-1907) proposed the Absolute or Kelvin scale (based on his study of

15 3-15 Temperature Scales (Con t) 1848 Lord Kelvin (William Thomson ) proposed the Absolute or Kelvin scale (based on his study of gases and thermodynamics) that led to more physical meaning of zero. Mathematicians/Thomson.html

16 3-16 Temperature Scales (Con t) Boiling Point of Water Freezing Point of Water Absolute Zero Fahrenheit Temperature Conversions Fahrenheit to Celsius C = 5/9 ( F - 32 ) Celsius to Kelvin K = ( C ) Celsius Kelvin or Absolute

17 Observing Climate - Wind Chill 3-17 Quote The wind was particularly bitter, even for January in Holloman, Connecticut. When Dr. Joshua Christian strode round the corner from Cedar Street onto Elm Street it hit him full in the face, a stream of arctic air with fangs and talons of ice chewing and clawing at the little sections of facial skin he had to expose to see where he going. Colleen McCullough, "A Creed For The Third Millennium" What is wind the wind chill? chill temperature? Definition How cold was it? When the farmers went to milk their cows, they got ice cream. Wind Chill Temperature Index (WCTI) is an effective temperature not an actual temperature Wind Chill Temperature Index is related to an object's rate of cooling Bulletin of the American Meteorological Society, 2005: Coin-aphenomenon #3, 86, 1221.

18 Observing Climate - Wind Chill 3-18 Definition (Con t) Siple, P.A., and C.F. Passel, 1945: Measurements of dry atmospheric cooling in subfreezing temperatures. Proc. Amer. Philos. Soc., 89, Late 40s, Siple and Passel, Antarctic explorers, measured time it took to freeze 250 g of water in a plastic contained on a pole in different temperature and wind conditions Developed empirical equations relating these data to the rate of heat loss from exposed human skin or T (Chill) = 33 - ( * SQRT ( V ) - V ) * ( 33 - T ) / where V is in units of m / s and T is in C T (Chill) = ( 3.71 * SQRT ( V ) V ) * ( T ) where V is in units of mph and T is in F. At wind speeds of 4 mph or less, the Wind Chill Temperature Index is the same as the actual air temperature.

Observing Climate - Wind Chill 3-19 Definition (Con t) 1 November 2001, the Weather Service began using a new Wind Chill Temperature Index (WCTI) equation.

19 Observing Climate - Wind Chill 3-19 Definition (Con t) 1 November 2001, the Weather Service began using a new Wind Chill Temperature Index (WCTI) equation. New WCTI equation uses: - Calculated wind speed at an average height of 5 ft (typical height of an adult human face) - A human face model - Modern heat transfer theory - A calm wind threshold of 3 mph - A consistent standard for skin tissue resistance - No impact from the sun (i.e., clear night sky). T (Chill) = T V T V 0.16 Osczevski, R., and M. Bluestein, 2005: The new wind chill equivalent temperature chart. Bull. Amer. Meteor. Soc., 86, where V is in mph and T in F. For wind speeds less than 3 mph, the new Wind Chill Temperature Index equals the actual air temperature.

20 Observing Climate - Wind Chill 3-20 Wind Speed (mph) ( F) Frostbite occurs in 5 minutes Frostbite occurs in 10 minutes Frostbite occurs in 30 minutes

21 Observing Climate - Heat Index 3-21 What is the Heat Index? What is the Heat Index? Definition Heat Index is also an effective temperature not an actual temperature Heat Index is related to an object's rate of cooling Heat Index relates to how our body feels?

22 Observing Climate - Heat Index 3-22 AIR TEMPERATURE ( F) RH (%) Heat Index Prolonged exposure and physical activity (especially if in poor physical condition and overweight, sedentary lifestyle) likely to lead to heat exhaustion. Heat Index Heat exhaustion possible with prolonged exposure and physical activity, even if in good physical condition unless hydration is maintained. Heat Index >130 Do not engage in strenuous physical activity.

Lecture 6. Temperature and Heat 27 September 2018

Lecture 6. Temperature and Heat 27 September 2018 Wannapong Triampo, Ph.D. Korey Stringer 7-31-01 27 Yrs Old 6 3 335 lbs Eraste Autin 7-25-01 18 Yrs Old 6 2 250 lbs Preston Birdsong 8-13-00 18 Yrs Old