2. ATM OCN 100 Summer 2002 1 ATM OCN 100 - Summer 2002 LECTURE 9 BEHAVIOR OF GASES in the ATMOSPHERE: Thermodynamics (con’t.) A. Introduction B. Kinetic Theory of Matter C. The Gas Laws Equation of State Dalton’s Law D. The Laws of Thermodynamic E. Vertical Motions F. Stability

3. MADISON’S CURRENT WEATHER at 900 AM CDT MON OCT 8 2001 Updated twice an hour at :05 and :25 Sky/Weather: MOSUNNY Temperature: 47 F (8 C) Dew Point: 32 F (0 C) Relative Humidity: 56% Wind: S13 MPH Barometer: 30.29R

4. ATM OCN 100 Summer 2002 3 Surface Weather Map from Today with Isobars & Fronts

5. ATM OCN 100 Summer 2002 4 Iris CURRENT IR

6. ATM OCN 100 Summer 2002 5 CURRENT VISIBLE

7. ATM OCN 100 Summer 2002 6 Hurricane Iris – A Cat. 4

8. ATM OCN 100 Summer 2002 7 Surface Weather Map from Today with Isobars & Fronts

9. ATM OCN 100 Summer 2002 8 Current Temperatures (°F) & Isotherms

10. ATM OCN 100 Summer 2002 9 Current Temperatures ( o F) – 24 Hrs Ago

11. ATM OCN 100 Summer 2002 10 Tomorrow’s 7AM Forecast

12. ATM OCN 100 Summer 2002 11 Announcements u Homework 2 is due today. u Exam on Monday here (more @ end of class). u Study sheet is online. u Answers to Homeworks 1 & 2 to be posted.

13. MADISON’S CURRENT WEATHER Madison Weather at 1000 AM CDT 8 JUL 2002 Updated twice an hour at :05 and :25 Sky/Weather: MOSUNNY Temperature: 83 F (28 C) Dew Point: 71 F (21 C) Relative Humidity: 67% Wind: SW9 MPH Barometer: 30.09F (1018.9 mb)

14. ATM OCN 100 Summer 2002 13 CURRENT VISIBLE

15. ATM OCN 100 Summer 2002 14 Current Surface Weather Map with Isobars (“iso” = equal & “bar” = weight), Fronts and Radar

16. ATM OCN 100 Summer 2002 15 Current Surface Winds with Streamlines & Isotachs (“iso” = equal & “tach” = speed) H L L H H L L

17. ATM OCN 100 Summer 2002 16 Yesterday’s High Temperatures ( o F) – (1961-90) Average High Temperatures

18. ATM OCN 100 Summer 2002 17 Current Temperatures ( ° F) & Isotherms (“iso” = equal +”therm” = temperature)

19. ATM OCN 100 Summer 2002 18 Current Temperatures ( o F) – 24 Hrs Ago

20. ATM OCN 100 Summer 2002 19 CURRENT IR

21. ATM OCN 100 Summer 2002 20 Current Dewpoints ( o F)

22. ATM OCN 100 Summer 2002 21 Tomorrow AM Forecast Map

23. ATM OCN 100 Summer 2002 22 Last 24 hrs in Madison Local Noon SunsetSunrise

24. ATM OCN 100 Summer 2002 23 ATM OCN 100 - Summer 2002 LECTURE 9 BEHAVIOR OF GASES in the ATMOSPHERE: Thermodynamics (con’t.) A. Introduction B. Kinetic Theory of Matter C. The Gas Laws Equation of State Dalton’s Law D. The Laws of Thermodynamic E. Vertical Motions F. Stability

25. ATM OCN 100 Summer 2002 24 ATM OCN 100 – Summer 2002 LECTURE 9 THERMODYNAMICS: BEHAVIOR OF GASES IN THE ATMOSPHERE A. INTRODUCTION – How are pressure & temperature related? – Why are lows cloudy and highs fair?

26. ATM OCN 100 Summer 2002 25 B. KINETIC THEORY OF MATTER Definitions Definitions Historical Historical

27. ATM OCN 100 Summer 2002 26 B. KINETIC THEORY OF MATTER Definitions Definitions Historical Historical Assumptions for gases: Assumptions for gases: – Tiny molecules with large space; – No attraction between molecules; – Random molecular motion; – Elastic molecular collisions.

28. ATM OCN 100 Summer 2002 27 B. KINETIC THEORY OF MATTER (con’t.) Molecular Diffusion Molecular Diffusion – Transport of fluid properties by molecular motion; – Direction is from high toward low concentration regions.

29. ATM OCN 100 Summer 2002 28 B. KINETIC THEORY OF MATTER (con’t.) u Variables describing molecular state of a gas – Density = molecular mass per volume – Temperature ~ average molecular speed – Pressure ~ molecular momentum change ( ~ molecular speed & mass)

30. ATM OCN 100 Summer 2002 29 C. THE GAS LAWS u Classical approach to Ideal Gas Law (or Equation of State)

31. ATM OCN 100 Summer 2002 30 F F Atmospheric application of Ideal Gas Law – – If P = constant, then  increases as T decreases; – – If  = constant, then P increases when T increases; – – If T = constant, then  increases as P increases.

32. ATM OCN 100 Summer 2002 31 C. THE GAS LAWS (con’t.) u Dalton's Laws of Partial Pressures – Involves mixture of ideal gases; – Each gas species has own partial pressure, p(i). – Then: Total Pressure = Sum of partial pressures

33. ATM OCN 100 Summer 2002 32 C. THE GAS LAWS (con’t.) u Atmospheric Applications of Dalton's Laws of Partial Pressures – P Total = p(N 2 ) + p(O 2 ) + p(Ar) + e +... – Where p(N 2 ), p(O 2 ), p(Ar) are partial pressures of major atmospheric gases & e = (partial water) vapor pressure. – So for air with some moisture: P Total = 1020 mb  (780 + 210 + 9) mb + e  (20 to 40 mb)

34. ATM OCN 100 Summer 2002 33 D. THE THERMODYNAMIC LAWS Introduction Introduction First Law of Thermodynamics First Law of Thermodynamics Input = Output + Storage

35. ATM OCN 100 Summer 2002 34 D. THE THERMODYNAMIC LAWS (con’t.) Atmospheric application of First Law of Thermodynamics Atmospheric application of First Law of Thermodynamics Heat exchange = Work + Internal energy Change – Heat exchange by radiation, etc.; – Work by volume change; – Internal energy change by temperature change.

36. ATM OCN 100 Summer 2002 35 D. THE THERMODYNAMIC LAWS (con’t.) Adiabatic Processes Adiabatic Processes – No heat exchanged with environment; Work = internal energy change – Involves volume change only: Volume change = Temperature change Volume change = Temperature change F Volume decrease ( or Pressure increase) causes heating; F Volume increase ( or Pressure decrease) causes cooling.

37. ATM OCN 100 Summer 2002 36 E. THE VERTICAL MOTION PROBLEM Response of an air parcel Response of an air parcel Rising motion: Encounters lower pressure Expansion & cooling Rising motion: Encounters lower pressure Expansion & cooling Sinking motion: Encounters higher pressure Compression & warming Sinking motion: Encounters higher pressure Compression & warming Specification of the response Specification of the response

38. ATM OCN 100 Summer 2002 37 Recall AIR PRESSURE CLIMATOLOGY See Fig. 5.4 Moran & Morgan (1997) 1 mb drop for 10 meter height rise

39. ATM OCN 100 Summer 2002 38 Response of Ascent/Descent of Air Parcel: Dry Adiabatic Lapse Rate (10C°/1000m) See Fig. 6.8 Moran & Morgan (1997) P  900 mb, V= 1.07 m 3 P  800 mb, V= 1.16 m 3 P  700 mb, V= 1.28 m 3 P  600 mb, V= 1.44 m 3 T = 20  C, P  1000 mb, V= 1.00 m 3

40. ATM OCN 100 Summer 2002 39 Response of Ascent/Descent of Air Parcel: Dry Adiabatic Lapse Rate See Fig. 6.8 Moran & Morgan (1997)

41. ATM OCN 100 Summer 2002 40 E. VERTICAL MOTION (con’t.) Specification of parcel response Specification of parcel response describes cooling/heating by adiabatic expansion/compression process; describes cooling/heating by adiabatic expansion/compression process; assume dry air parcel. assume dry air parcel. The dry adiabatic lapse rate (DALR) The dry adiabatic lapse rate (DALR) Recall that lapse rate is how temperature decreases with height; Recall that lapse rate is how temperature decreases with height; DALR  10 C o per 1000 meters or 5.5 F o per 1000 feet. DALR  10 C o per 1000 meters or 5.5 F o per 1000 feet.

42. ATM OCN 100 Summer 2002 41 E. VERTICAL MOTION (con’t.) Response of an air parcel Response of an air parcel An example An example

43. ATM OCN 100 Summer 2002 42 U.S. STANDARD ATMOSPHERE See Fig. 1.9 Moran & Morgan (1997) Troposphere Stratosphere Mesosphere Thermosphere Tropopause Stratopause Mesopause

44. ATM OCN 100 Summer 2002 43 GREEN BAY RADIOSONDE SOUNDING Sunday PM

45. ATM OCN 100 Summer 2002 44 Why does the Hot Air Balloon Rise?

46. ATM OCN 100 Summer 2002 45 When Convection?

47. ATM OCN 100 Summer 2002 46 F. STATIC STABILITY Importance Importance Stability-Instability Concept Stability-Instability Concept Stable: Return to initial state Stable: Return to initial state Unstable: Continuation away from initial state Unstable: Continuation away from initial state Criteria for Static Stability (Instability) Determination Criteria for Static Stability (Instability) Determination

48. ATM OCN 100 Summer 2002 47 STABLE CONDITIONS Compare Environment with DALR Colder parcel sinks & returns to start Parcel is colder & more dense Environment is warmer & less dense

49. ATM OCN 100 Summer 2002 48 UNSTABLE CONDITIONS Compare Environment with DALR Warmer parcel continues upward Parcel is warmer & less dense Environment is colder & more dense

50. ATM OCN 100 Summer 2002 49 GREEN BAY RADIOSONDE SOUNDING Wednesday PM

51. ATM OCN 100 Summer 2002 50 GREEN BAY RADIOSONDE SOUNDING FRIDAY AM

52. ATM OCN 100 Summer 2002 51 F. STATIC STABILITY (con’t.) Processes which change static stability (instability) Processes which change static stability (instability) Cool below, but warm above (stabilize)Cool below, but warm above (stabilize) Warm below, but cool above (destabilize)Warm below, but cool above (destabilize) Visual stability indicators Visual stability indicators

53. ATM OCN 100 Summer 2002 52 Example of Stabilization– An Inversion

54. ATM OCN 100 Summer 2002 53 Example of Destabilization-- Cumulonimbus

55. ATM OCN 100 Summer 2002 54 F. STATIC STABILITY (con’t.) Processes which change static stability (instability) Processes which change static stability (instability) Visual stability indicators Visual stability indicators Graphical Analysis: The Thermodynamic Diagram Graphical Analysis: The Thermodynamic Diagram

56. ATM OCN 100 Summer 2002 55

57. 56

58. 57 GREEN BAY RADIOSONDE SOUNDING Sunday PM

59. ATM OCN 100 Summer 2002 58 ATM OCN 100 - Summer 2002 LECTURE 9 BEHAVIOR OF GASES in the ATMOSPHERE: Thermodynamics (con’t.) A. Introduction B. Kinetic Theory of Matter C. The Gas Laws D. The Laws of Thermodynamic E. Vertical Motions F. Stability

60. MADISON’S CURRENT WEATHER Madison Weather at 1000 AM CDT THU JUL 5 2001 Updated twice an hour at :05 and :25 Sky/Weather: SUNNY Temperature: 63 F (17 C) Dew Point: 42 F (5 C) Relative Humidity: 46% Wind: N7 MPH Barometer: 30.10S

61. ATM OCN 100 Summer 2002 60 Surface Weather Map from Today with Isobars & Fronts

62. ATM OCN 100 Summer 2002 61 Current Temperatures ( o F) & Isotherms

63. ATM OCN 100 Summer 2002 62 Current Dewpoints ( o F)

64. ATM OCN 100 Summer 2002 63

65. 64

66. 65 Tomorrow’s 7AM Forecast

67. ATM OCN 100 Summer 2002 66 Current UVI Forecast

68. ATM OCN 100 Summer 2002 67 Last 24 hrs in Madison

69. ATM OCN 100 Summer 2002 68

70. 69 At Southern Lake Michigan Buoy

71. ATM OCN 100 Summer 2002 70 Announcements u Homework 2 is due today. u Exam on Monday here (more @ end of class). u Study sheet is online. u Answers to Homeworks 1 & 2 to be posted.

72. ATM OCN 100 Summer 2002 71 U.S. STANDARD ATMOSPHERE See Fig. 1.9 Moran & Morgan (1997) Troposphere Stratosphere Mesosphere Thermosphere Tropopause Stratopause Mesopause

73. ATM OCN 100 Summer 2002 72 GREEN BAY RADIOSONDE SOUNDING Sunday PM

74. ATM OCN 100 Summer 2002 73 GREEN BAY RADIOSONDE SOUNDING Wednesday PM

75. ATM OCN 100 Summer 2002 74 GREEN BAY RADIOSONDE SOUNDING Wednesday PM

76. ATM OCN 100 Summer 2002 75 GREEN BAY RADIOSONDE SOUNDING FRIDAY AM

77. ATM OCN 100 Summer 2002 76

78. 77

79. 78 GREEN BAY RADIOSONDE SOUNDING Sunday PM

80. ATM OCN 100 Summer 2002 79 GREEN BAY RADIOSONDE SOUNDING Wednesday PM

81. ATM OCN 100 Summer 2002 80 GREEN BAY RADIOSONDE SOUNDING FRIDAY AM

82. ATM OCN 100 Summer 2002 81 GREEN BAY RADIOSONDE SOUNDING FRIDAY AM

83. ATM OCN 100 Summer 2002 82 Announcements u Homeworks 1 & 2 –Please Pick up yours in front –Ans. Keys for both are posted at http://www.aos.wisc.edu/~hopkins/aos100/homework. u First Hour Exam –Is scheduled for Next Friday; –A review/help sheet has been posted at: http://www.aos.wisc.edu/~hopkins/aos100/exams. u Honors students – Have you talked with me?

84. MADISON’S CURRENT WEATHER at 900 AM CDT MON OCT 8 2001 Updated twice an hour at :05 and :25 Sky/Weather: MOSUNNY Temperature: 47 F (8 C) Dew Point: 32 F (0 C) Relative Humidity: 56% Wind: S13 MPH Barometer: 30.29R

85. ATM OCN 100 Summer 2002 84 Surface Weather Map from Today with Isobars & Fronts

86. ATM OCN 100 Summer 2002 85 Iris CURRENT IR

87. ATM OCN 100 Summer 2002 86 CURRENT VISIBLE

88. ATM OCN 100 Summer 2002 87 Hurricane Iris – A Cat. 4

89. ATM OCN 100 Summer 2002 88 Surface Weather Map from Today with Isobars & Fronts

90. ATM OCN 100 Summer 2002 89 Current Temperatures (°F) & Isotherms

91. ATM OCN 100 Summer 2002 90 Current Temperatures ( o F) – 24 Hrs Ago

92. ATM OCN 100 Summer 2002 91 Tomorrow’s 7AM Forecast

93. ATM OCN 100 Summer 2002 92 Announcements u Homework 1 –Please Pick up yours in front. u Homework 2 –Is being graded; –NOTE: If you are had trouble with the extra- credit, you may submit this section after class. u Honors students – Have you talked with me?

94. ATM OCN 100 Summer 2002 93 Announcements u Homework 2 is due today. u Exam on Monday here (more @ end of class). u Study sheet is online. u Answers to Homeworks 1 & 2 to be posted.