1. ATM OCN 100 Summer 2002 1 ATM OCN 100 – Summer 2002 LECTURE 5 (con’t.) AIR TEMPERATURE: A Fundamental Weather Element u A. Background & Definitions u B. Thermometry u C. Near-surface air temperature climatology

2. MADISON’S CURRENT WEATHER Madison Weather at 1000 AM CDT MON 24 JUN 2002 Updated twice an hour at :05 and :25 Sky/Weather: SUNNY Temperature: 81 F (27 C) Dew Point: 64 F (17 C) Relative Humidity: 56% Wind: SW6 MPH Barometer: 30.11F (1019.6 mb)

3. ATM OCN 100 Summer 2002 3 Current Surface Winds with Streamlines & Isotachs (“iso” = equal & “tach” = speed) H L L H L H

4. ATM OCN 100 Summer 2002 4 Current Surface Weather Map with Isobars (“iso” = equal & “bar” = weight), Fronts and Radar

5. ATM OCN 100 Summer 2002 5 Current Temperatures ( ° F) & Isotherms (“iso” = equal +”therm” = temperature)

6. ATM OCN 100 Summer 2002 6 This morning’s low temperatures ( o F)

7. ATM OCN 100 Summer 2002 7 Yesterday’s high temperatures ( o F)

8. ATM OCN 100 Summer 2002 8 Yesterday’s High Temperatures ( o F) – (1961-90) Average High Temperatures

9. ATM OCN 100 Summer 2002 9 Current Dewpoints ( o F)

10. ATM OCN 100 Summer 2002 10 Current Apparent Temperatures ( o F)

11. ATM OCN 100 Summer 2002 11 Current Surface Weather Map with Isobars (“iso” = equal & “bar” = weight), Fronts and Radar

12. ATM OCN 100 Summer 2002 12 CURRENT IR GABRIELLE

13. ATM OCN 100 Summer 2002 13 Tomorrow AM Forecast Map

14. ATM OCN 100 Summer 2002 14 Announcements u Homework 1 –Get from our webpage F http://www.aos.wisc.edu/~hopkins/aos100/homework/ –Due this Thursday 27 June 2002

15. ATM OCN 100 Summer 2002 15 LATEST RADAR

16. ATM OCN 100 Summer 2002 16

17. 17 Current Surface Weather Map with Isobars (“iso” = equal & “bar” = weight), Fronts and Radar

18. ATM OCN 100 Summer 2002 18 Today is the Summer Solstice See Fig. 2.10 Moran & Morgan (1997)

19. ATM OCN 100 Summer 2002 19 Earth’s Orbit of Sun – The Cause of the Seasons See Fig. 2.10 Moran & Morgan (1997)

20. ATM OCN 100 Summer 2002 20 Today is the Autumnal Equinox See Fig. 2.10 Moran & Morgan (1997)

21. ATM OCN 100 Summer 2002 21

22. 22

23. 23 Track of Tropical Storm Helene

24. ATM OCN 100 Summer 2002 24 Surface Weather Map from Today with Isobars & Fronts

25. ATM OCN 100 Summer 2002 25 Forecast Weather Map for Tomorrow Morning

26. ATM OCN 100 Summer 2002 26 Current Temperatures ( o F) & Isotherms

27. ATM OCN 100 Summer 2002 27 Current Temperatures ( o F) – 24 Hrs Ago

28. ATM OCN 100 Summer 2002 28 Last 24 hrs in Madison

29. ATM OCN 100 Summer 2002 29 ATM OCN 100 - Summer 2002 LECTURE 5 AIR TEMPERATURE: A Fundamental Weather Element u A. BACKGROUND –Why do we want to know air temperature? – Meteorological Significance of Temperature F A measure of energy of atmosphere – Human Significance of Temperature F Humans are warm blooded; F Humans maintain a constant temperature.

30. ATM OCN 100 Summer 2002 30 THE DEFINITIONS u TEMPERATURE – A measure of “heat intensity” of object. – Proportional to average energy of motion of individual molecules; or to average molecular speed. u HEAT – A form of energy; – Proportional to total amount of thermal energy found in object.

31. ATM OCN 100 Summer 2002 31 B. THERMOMETRY u The Science of Thermometry – Measuring temperature. u Types of Thermometers – Liquid-in-glass thermometers – Deformation thermometers – Electrical thermometers – Radiation thermometers (radiometers) where... where...

32. ATM OCN 100 Summer 2002 32 LIQUID-IN-GLASS THERMOMETERS u Concept: – Volume of fluid (Liquid mercury or alcohol) proportional to temperature; – Measure expansion of liquid in sealed tube.

33. ATM OCN 100 Summer 2002 33 LIQUID-IN-GLASS THERMOMETERS (con’t.) u Special Recording Thermometers – Maximum recording thermometers (Mercury thermometers) – Minimum recording thermometers (Alcohol thermometers)

34. ATM OCN 100 Summer 2002 34 Maximum-Minimum Thermometers

35. ATM OCN 100 Summer 2002 35 DEFORMATION THERMOMETERS u Concept: – Length of material (e.g., metal) proportional to temperature; – Deflection of material monitored.

36. ATM OCN 100 Summer 2002 36 DEFORMATION THERMOMETERS u Example: – Bimetallic Thermometer; – Used in Thermostats & Thermographs.

37. ATM OCN 100 Summer 2002 37 ELECTRICAL THERMOMETERS u Concept: – Electrical resistance of material proportional to temperature; – Measure electric current. u Example: – Thermistor; – Used in radiosondes & automatic weather stations.

38. ATM OCN 100 Summer 2002 38 A Radiosonde

39. ATM OCN 100 Summer 2002 39 Thermistor on Radiosonde

40. ATM OCN 100 Summer 2002 40 Thermal Sensor at ASOS

41. ATM OCN 100 Summer 2002 41 RADIATION THERMOMETERS u Concept: – “Heat Radiation” from material proportional to object’s temperature; – Measure emitted radiation. u Example: – Radiometer; – Used on-board satellites.

42. ATM OCN 100 Summer 2002 42 Temperatures Retrieved from Infrared Satellite Imagery http://www.ametsoc.org/amsedu/WES/composite_ir.html

43. ATM OCN 100 Summer 2002 43 Example of Satellite-Based Radiometers: Current Sea Surface Temperatures from SSEC http://www.ssec.wisc.edu/data/sst/latest_sst.gif

44. ATM OCN 100 Summer 2002 44 THERMOMETRY [con’t.] u Measurement requirements – Standard instruments – Thermometer Exposure – Standardized observations

45. ATM OCN 100 Summer 2002 45 Surface Weather Station

46. ATM OCN 100 Summer 2002 46 Inside an Instrument Shelter

47. ATM OCN 100 Summer 2002 47 Automated NWS-FAA Surface Weather Station

48. ATM OCN 100 Summer 2002 48 Thermal Sensor at ASOS

49. ATM OCN 100 Summer 2002 49 THERMOMETRY [con’t] u Temperature Scales – Historical Background – The Fahrenheit, Celsius and Kelvin Scales – Temperature Scale Conversions where...

50. ATM OCN 100 Summer 2002 50 THERMOMETRY [con’t] u Temperature Scales – Historical Background F Need at least 2 reproducible points – The Fahrenheit, Celsius & Kelvin Scales

51. ATM OCN 100 Summer 2002 51 Reproducible Reference Temperature Points See Fig 4.3 Moran & Morgan (1997)

52. ATM OCN 100 Summer 2002 52 Temperature Scales Fig. 3.1 Moran & Morgan (1997)

53. ATM OCN 100 Summer 2002 53 TEMPERATURE SCALES (con’t.) u Relationships:

54. ATM OCN 100 Summer 2002 54 TEMPERATURE SCALES (con’t.) u Converting Fahrenheit to Celsius

55. ATM OCN 100 Summer 2002 55 TEMPERATURE SCALES (con’t.) u Converting Celsius to Fahrenheit

56. ATM OCN 100 Summer 2002 56 TEMPERATURE SCALES (con’t.) u Converting Celsius to Kelvin u Converting Kelvin to Celsius

57. ATM OCN 100 Summer 2002 57 C. THE CLIMATOLOGY of NEAR- SURFACE AIR TEMPERATURE u Temporal Variation in Air Temperature – diurnal cycle (afternoon maximum vs. sunrise minimum) – annual cycle (summer maximum vs. winter minimum)

58. ATM OCN 100 Summer 2002 58 January Temperatures - Madison, WI (1981-90)

59. ATM OCN 100 Summer 2002 59 July Temperatures - Madison, WI (1981-90)

60. ATM OCN 100 Summer 2002 60 Sample Meteorogram for Madison, WI

61. ATM OCN 100 Summer 2002 61 Last 24 hours for Madison, WI

62. ATM OCN 100 Summer 2002 62 Last 24 hours for Madison, WI

63. ATM OCN 100 Summer 2002 63

64. 64 C. THE CLIMATOLOGY of NEAR- SURFACE AIR TEMPERATURE u Temporal Variation in Air Temperature – diurnal cycle (afternoon maximum vs. sunrise minimum) – annual cycle (summer maximum vs. winter minimum) u Spatial Variation in Air Temperature – north-south (polar vs. tropical) – land-ocean (continental vs. maritime)

65. ATM OCN 100 Summer 2002 65

66. 66

67. 67

68. 68 This morning’s low temperatures ( o F)

69. ATM OCN 100 Summer 2002 69 Yesterday’s high temperatures ( o F)

70. ATM OCN 100 Summer 2002 70 Yesterday’s High Temperatures ( o F) – (1961-90) Average High Temperatures

71. ATM OCN 100 Summer 2002 71 C. THE CLIMATOLOGY of NEAR- SURFACE AIR TEMPERATURE (con’t.) u Average Daily Temperatures & Degree-Day Units – Background – Types of Degree-Day Units F Heating Degree-Day Units F Cooling Degree-Day Units F Growing Degree-Day Units – Degree-Day Units Computations (where...)

73. ATM OCN 100 Summer 2002 73 From NOAA: Climate Prediction Center

74. ATM OCN 100 Summer 2002 74

75. 75 DEGREE-DAY CALCULATIONS u Calculate daily average temperature & then Heating Degree-Day Units:

76. ATM OCN 100 Summer 2002 76 HEATING DEGREE-DAY CALCULATION u If T max = 40 o F and T min = 30 o F, then:

77. ATM OCN 100 Summer 2002 77 Annual Heating Degree Day Units See Fig. 3.11A Moran & Morgan (1997) 7493 149 10269 Point Barrow: 19674

78. ATM OCN 100 Summer 2002 78 DEGREE-DAY CALCULATIONS u Calculate daily average temperature & then Cooling Degree-Day Units:

79. ATM OCN 100 Summer 2002 79 COOLING DEGREE-DAY CALCULATION u If T max = 80 o F and T min = 60 o F, then:

80. ATM OCN 100 Summer 2002 80 D. VARIATION OF OBSERVED AIR TEMPERATURE WITH HEIGHT u Temperature lapse rates – Rate of temperature decrease with height – Units: Celsius degrees per 1000 meters or Fahrenheit degrees per 1000 feet u Layer nomenclature – lapse – inversion – isothermal where... where...

81. ATM OCN 100 Summer 2002 81 LAPSE CONDITIONS Temperature decreases with height

82. ATM OCN 100 Summer 2002 82 INVERSION CONDITIONS Temperature increases with height

83. ATM OCN 100 Summer 2002 83 ISOTHERMAL CONDITIONS Temperature remains constant with height

84. ATM OCN 100 Summer 2002 84 RADIOSONDE LOCATIONS

85. ATM OCN 100 Summer 2002 85 GREEN BAY RADIOSONDE SOUNDING TUES AM

86. ATM OCN 100 Summer 2002 86 TALAHASSEE RADIOSONDE SOUNDING TUES AM

87. ATM OCN 100 Summer 2002 87 U.S. STANDARD ATMOSPHERE See Fig. 1.9 Moran & Morgan (1997)

88. ATM OCN 100 Summer 2002 88 VERTICAL TEMPERATURE VARIATIONS (con’t.) The temperature spheres See Fig. 1.9 Moran & Morgan (1997) Troposphere Stratosphere Mesosphere Thermosphere Tropopause Stratopause Mesopause

89. ATM OCN 100 Summer 2002 89 U.S. STANDARD ATMOSPHERE See Fig. 1.9 Moran & Morgan (1997) Troposphere Stratosphere Mesosphere Thermosphere

90. ATM OCN 100 Summer 2002 90 VERTICAL TEMPERATURE VARIATIONS (con’t.) u The Standard Reference Atmosphere – The Temperature “Spheres” – The boundaries or “pauses” u Reasons for vertical temperature structure u Implications of vertical temperature structure

91. ATM OCN 100 Summer 2002 91 8 ppmv = 0.0008%

92. ATM OCN 100 Summer 2002 92 VERTICAL TEMPERATURE VARIATIONS (con’t.) u The Temperature Spheres – Troposphere – Stratosphere – Mesosphere – Thermosphere

93. ATM OCN 100 Summer 2002 93 VERTICAL TEMPERATURE VARIATIONS (con’t.) u The Standard Reference Atmosphere – The Temperature “Spheres” – The boundaries or “pauses”

94. ATM OCN 100 Summer 2002 94 U.S. STANDARD ATMOSPHERE See Fig. 1.9 Moran & Morgan (1997) Troposphere Stratosphere Mesosphere Thermosphere Tropopause Stratopause Mesopause

95. ATM OCN 100 Summer 2002 95 VERTICAL TEMPERATURE VARIATIONS (con’t.) u The Standard Reference Atmosphere – The Temperature “Spheres” – The boundaries or “pauses” u Reasons for vertical temperature structure u Implications of vertical temperature structure

96. ATM OCN 100 Summer 2002 96 U.S. STANDARD ATMOSPHERE See Fig. 1.9 Moran & Morgan (1997) Troposphere Stratosphere Mesosphere Thermosphere Tropopause Stratopause Mesopause

97. ATM OCN 100 Summer 2002 97 RADIOSONDE LOCATIONS

98. ATM OCN 100 Summer 2002 98 GREEN BAY RADIOSONDE SOUNDING TUES AM

99. ATM OCN 100 Summer 2002 99 TALAHASSEE RADIOSONDE SOUNDING TUES AM

100. ATM OCN 100 Summer 2002 100 GREEN BAY RADIOSONDE SOUNDING Monday PM

101. ATM OCN 100 Summer 2002 101 GREEN BAY RADIOSONDE SOUNDING Tuesday AM

102. ATM OCN 100 Summer 2002 102 ANCHORAGE RADIOSONDE SOUNDING Monday PM

103. ATM OCN 100 Summer 2002 103

104. 104

105. 105

106. 106 See Fig. 19.9 Moran & Morgan (1997)

107. ATM OCN 100 Summer 2002 107 See Fig. 19.9 Moran & Morgan (1997)