1. MADISON’S CURRENT WEATHER
Madison Weather at AM CDT 31 JUL 2002
Updated twice an hour at :05 and :25
Sky/Weather: MOSUNNY
Temperature: 83 F (28 C)
Dew Point: 66 F (18 C)
Relative Humidity: 56%
Wind: SW8 MPH
Barometer: 30.00S ( mb)

2.                                                                                                                                                                     
Last 24 hrs in Madison
FOG

3.
CURRENT VISIBLE

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

5. Current Temperatures (°F) & Isotherms (“iso” = equal +”therm” = temperature)

6. Current Dewpoints (oF)

7. Tomorrow AM Forecast Map

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

9. H L L L L H L H L L H H L H L L L L H H H H
Current Surface Winds with Streamlines & Isotachs (“iso” = equal & “tach” = speed) H L L L L H L H L L H H L H L L L L H H H H

10. Current 5,000 ft. Winds with Streamlines & Isotachs (“iso” = equal & “tach” = speed)

11. Current 10,000 ft. Winds with Streamlines & Isotachs (“iso” = equal & “tach” = speed)

12. Current 34,000 ft. Winds & Jet Stream with Streamlines & Isotachs (“iso” = equal & “tach” = speed)
Trough
Ridge

13. ATM OCN 100 - Spring 2002 LECTURE 20 (con’t.)
THE THEORY OF WINDS: PART III - RESULTANT ATMOSPHERIC MOTIONS (con’t.)
Introduction & Assumptions
Buys-Ballot Law
Hydrostatic Balance Relationship
Horizontal Equation of Motion
Local Winds
Geostrophic Winds
Winds in Friction Layer

14. Summary of Forces for selected models See Table 9
Summary of Forces for selected models See Table 9.1 Moran & Morgan (1997)
MODELS

15. Current Midwest Weather Plot

16. L H Current Midwest Weather Analysis H

17. Flow in Friction Layer See Fig. 9.15 Moran & Morgan (1997)
No Friction
Geostrophic
Friction
Subgeostrophic

18. Flow in Friction Layer See Fig. 9.15 Moran & Morgan (1997)
Vector Magnitude 1. Depends on Friction
2. Less than Geostrophic Wind
Vector Direction:
Angles across isobars
Toward Low in either hemisphere

19. Observation: Right with Height

20. Variation of Friction Effects with Height See Fig. 9
Variation of Friction Effects with Height See Fig Moran & Morgan (1997)

21. Varying effects of Surface Roughness

22. Variations in Surface Roughness leads to divergence/convergence patterns See Fig Moran & Morgan (1997)

23. F. CURVED, HORIZONTAL BALANCED MOTION - “GRADIENT FLOW”
Assumptions
Without Friction
Two Cases

24. Summary of Forces for selected models See Table 9
Summary of Forces for selected models See Table 9.1 Moran & Morgan (1997)

25. “GRADIENT” FLOW: ANTICYCLONIC Case See Fig. 9
“GRADIENT” FLOW: ANTICYCLONIC Case See Fig Moran and Morgan (1997):

26. “GRADIENT” FLOW: ANTICYCLONIC Case See Fig. 9
“GRADIENT” FLOW: ANTICYCLONIC Case See Fig Moran and Morgan (1997):

27. “GRADIENT” FLOW: CYCLONIC Case See Fig. 9.14 Moran and Morgan (1997):

28. “GRADIENT” FLOW: CYCLONIC Case See Fig. 9.14 Moran and Morgan (1997):

29. G. GRADIENT FLOW WITH FRICTION
Resultant flow with Friction FCentripetal = FPG,H + FCor + FFriction (A vector summation).

30. Summary of Forces for selected models See Table 9
Summary of Forces for selected models See Table 9.1 Moran & Morgan (1997)

31. G. GRADIENT FLOW WITH FRICTION
Resultant flow with Friction FCentripetal = FPG,H + FCor + FFriction (A vector summation).
Applicability to the Atmosphere
Situation
Resultant Diagrams

32. Anticyclonic Flow in Friction Layer
Fig Moran & Morgan (1997)

33. Cyclonic Flow in Friction Layer
Fig Moran & Morgan (1997)

34. Near-Surface Winds in each Hemisphere See Figs. 9. 17 & 9
Near-Surface Winds in each Hemisphere See Figs & 9.18 Moran & Morgan (1997)

35. Summary of Forces for selected models See Table 9
Summary of Forces for selected models See Table 9.1 Moran & Morgan (1997)

36. H. RELATIONSHIPS BETWEEN HORIZONTAL & VERTICAL MOTIONS
Dilemma
Convergence / Divergence
Principle of Mass Continuity

37. Features in a Surface Low (Convergence & Ascent)

38. Features in a Surface High (Sinking & Divergence)

39. H. RELATIONSHIPS BETWEEN HORIZONTAL & VERTICAL MOTIONS (con’t.)
Dines’ Compensation
Resultant Vertical Motions
Implications of Dines' Compensation

40. I. VORTICES & VORTICITY
Definitions
Characteristic Vortex Features

41. Anticyclonic Vorticity
Types of Vorticity
Cyclonic Vorticity
Anticyclonic Vorticity

42. Vorticity Conservation of Vorticity

43. ATM OCN 100 - Summer 2002 LECTURE 24 PLANETARY-SCALE CIRCULATION of EARTH'S ATMOSPHERE
A. INTRODUCTION
Why do weather systems in mid latitudes move from west to east? but.. tropics move from east to west?

44. Typical Movement of Storms

45. Year 2001 Hurricane/Tropical Storm Tracks in North Atlantic
8 Hurricanes
7 Trop. Storms

46. Year 2001 Hurricane/Tropical Storm Tracks in Eastern/Central North Pacific
8 Hurricanes
7 Trop. Storms

47. B. GLOBAL SCALE PREVAILING SURFACE WINDS
Historical Wind Observations
Popular Names of Principal Prevailing Surface Wind Regimes
Where…

48. Popular Names of Global-Scale Prevailing Wind Belts
Polar easterlies
Westerlies
Horse Latitudes
NE Trades
Doldrums
SE Trades
Horse Latitudes
Westerlies
Polar easterlies

49. Average Air Pressure & Atmospheric Circulation
Polar Highs (or anticyclones)
Subpolar Lows (or cyclones)
Subtropical High Pressure Cells
Intertropical Convergence Zone (ITCZ)
~ Subtropical High Pressure Cells
Subpolar Lows (or cyclones

50. Relationships between Prevailing winds & Major Pressure Patterns
C. AVERAGE SEA-LEVEL PRESSURE PATTERNS See Table 10.1 Moran & Morgan (1997)
Relationships between Prevailing winds & Major Pressure Patterns

51. Planetary Scale Circulation Regime See Figure 10
Planetary Scale Circulation Regime See Figure 10.4, Moran & Morgan (1997)

52. PRESSURE PATTERNS (con’t.)
Relationships between winds, “centers of action” & oceanic circulation.

53. OCEAN CURRENTS

54. Gulf Stream

55. Current Sea Surface Temperature

56. Sea Surface Temperature – Late Fall

57. PRESSURE PATTERNS (con’t.)
Relationships between “centers of action”, clouds & precipitation.

58. Current Satellite Composite

59. December Satellite Composite

60. Average Cloudiness -- Annual

61. Annual Percent Possible Sunshine

62. ANNUAL AVERAGE CONTINENTAL PRECIPITATION

63. PRESSURE PATTERNS (con’t.)
Relationships between “Centers of Action” & Major Biome Patterns
Tropical Rain Forests
Subtropical Deserts
Mid latitude Biomes
Polar Deserts

64. LANDCOVER (VEGETATION DISTRIBUTION) Oak Ridge National Laboratory

65. Global Biosphere From NASA (Goddard Space Flight Center)

66. Köppen Climate Classification Scheme See Fig. 18
Köppen Climate Classification Scheme See Fig Moran & Morgan (1997)

67. D. PLANETARY SCALE CIRCULATION: THEORETICAL ASPECTS
Historical Perspective
George Hadley in 1730’s
William Ferrel in 1850’s

68. Simple Thermal Circulation Cells

69. Simple Thermal Circulation on a non-rotating earth See Fig. 10
Simple Thermal Circulation on a non-rotating earth See Fig A Moran & Morgan (1997)

70. HADLEY’S MODEL See Fig. 10.1 A&B Moran & Morgan (1997)

71. More Recent Model of Planetary Atmospheric Circulation on a Rotating Earth See Fig C&D Moran & Morgan (1997)

72. See Fig. 10.1 C&D Moran & Morgan (1997)

73. Cross Sections through the Tropical Hadley Circulation Cells Fig. 10
Cross Sections through the Tropical Hadley Circulation Cells Fig Moran & Morgan (1997)

74. North-South View of Planetary Scale Circulation Figure 10
North-South View of Planetary Scale Circulation Figure 10.7 Moran & Morgan (1997)

75. D. PLANETARY SCALE CIRCULATION: THEORETICAL ASPECTS (con’t.)
Overall Observed Vertical Wind Structure
Discovery of the Jet Stream

76. Average 300 mb jet stream winds - Jan