2. ATM OCN 100 Summer 2002 1 ATM OCN 100 - Summer 2002 LECTURE 17 (con’t.) THE THEORY OF WINDS: PART I - OBSERVATIONS & SCALES A. Introduction B. Wind Observations & Anemometry C. Characteristic Scales of Atmospheric Motion

3. ATM OCN 100 Summer 2002 2Announcements u Homework 5: –Has been posted on the Web at: –http://www.aos.wisc.edu/~hopkins/aos100/homework; http://www.aos.wisc.edu/~hopkins/aos100/homework –Due this Friday u 2 nd Hour Exam: –Is scheduled this Friday (16 Nov. 2001) –A help sheet has been posted at: –http://www.aos.wisc.edu/~hopkins/aos100/exams. http://www.aos.wisc.edu/~hopkins/aos100/exams –Please stay tuned for more info!!! u Homework 4 (also 1-3): –Has been graded and available in the front; please retrieve yours (along with previous items); –Answers to be posted on the Web at: –http://www.aos.wisc.edu/~hopkins/aos100/homework; http://www.aos.wisc.edu/~hopkins/aos100/homework

4. ATM OCN 100 Summer 2002 3 Last 24 hrs in Madison Example of Cold Air Advection

5. MADISON’S CURRENT WEATHER Madison Weather at 1000 AM CDT 24 JUL 2002 Updated twice an hour at :05 and :25 Sky/Weather: MOSUNNY Temperature: 71 F (21 C) Dew Point: 56 F (13 C) Relative Humidity: 58% Wind: SE10 MPH Barometer: 30.27S (1025.0 mb)

6. ATM OCN 100 Summer 2002 5 Last 24 hrs in Madison FOG

7. ATM OCN 100 Summer 2002 6 http://www.ssec.wisc.edu/data/comp/cmoll.mpg

8. 7 CURRENT VISIBLE

9. ATM OCN 100 Summer 2002 8 CURRENT IR

10. ATM OCN 100 Summer 2002 9 Current Surface Weather Map with Isobars (“iso” = equal & “bar” = weight), Fronts and Radar

11. ATM OCN 100 Summer 2002 10 Current Surface Winds with Streamlines & Isotachs (“iso” = equal & “tach” = speed) L L H H LL H L L H L H H H L LL

12. ATM OCN 100 Summer 2002 11 Current Temperatures ( ° F) & Isotherms (“iso” = equal +”therm” = temperature)

13. ATM OCN 100 Summer 2002 12 Current Temperatures ( o F) – 24 Hrs Ago Cold Advection + Drier Air

14. ATM OCN 100 Summer 2002 13 Current Dewpoints ( o F)

15. ATM OCN 100 Summer 2002 14 Tomorrow AM Forecast Map

16. ATM OCN 100 Summer 2002 15

17. 16Typhoon

18. 17

19. 18 Hurricane Douglas

20. ATM OCN 100 Summer 2002 19

21. 20 Announcements u Homework #3 Answer Key is posted at http://www.aos.wisc.edu/~hopkins/aos100/homework http://www.aos.wisc.edu/~hopkins/aos100/homework u Homework #4 is due tomorrow u 2 nd Hour Exam is scheduled for tomorrow. u Study sheet is posted at: http://www.aos.wisc.edu/~hopkins/aos100/exams http://www.aos.wisc.edu/~hopkins/aos100/exams u If you have ??, please see me.

22. ATM OCN 100 Summer 2002 21 ATM OCN 100 - Summer 2002 LECTURE 17 (con’t.) THE THEORY OF WINDS: PART I - OBSERVATIONS & SCALES A. Introduction –Nature of winds (and scalar quantities) –Importance of Winds

23. ATM OCN 100 Summer 2002 22 ATM OCN 100 - Summer 2002 LECTURE 17 THE THEORY OF WINDS: PART I - OBSERVATIONS & SCALES A. INTRODUCTION –What are Winds? –Importance of Winds

24. ATM OCN 100 Summer 2002 23 Current Midwest Winds & Isobars H

25. ATM OCN 100 Summer 2002 24 WINDS ARE: u Air in motion relative to earth’s surface; u Roughly horizontal; u Vector quantities, defined by: –Magnitude (speed) & –Direction F Compare vector with scalar quantities Wind, force vs. temperature, humidity. u Note: Winds are named for direction from which they come! (e.g., North wind is from north!)

26. ATM OCN 100 Summer 2002 25 Surface Weather Map from Today with Isobars & Fronts

27. ATM OCN 100 Summer 2002 26 Current Winds H L

28. ATM OCN 100 Summer 2002 27 Graphical Display of Wind Data Speed & Direction

29. ATM OCN 100 Summer 2002 28 IMPORTANCE OF WINDS: u Human Significance –Destructive aspect –Cooling power –Renewable resource (Wind Power) Since wind power is proportional to cube of wind speed. u Meteorological Significance –Atmospheric circulation –Advection of atmospheric properties

30. ATM OCN 100 Summer 2002 29

31. 30 Old Dutch Windmill

32. ATM OCN 100 Summer 2002 31 Modern Wind Energy Conversion System (NE Wisconsin)

33. ATM OCN 100 Summer 2002 32 Wind Power Potential National Wind Technology Center, U.S DOE

34. ATM OCN 100 Summer 2002 33 B. WIND OBSERVATIONS & ANEMOMETRY u Requirements –Representative & away from obstacles u Historical Wind Observations –Tower of Winds in Greece (1 st Century BC) (Boreas - the north wind, etc.)

35. ATM OCN 100 Summer 2002 34 B. WIND OBSERVATIONS & ANEMOMETRY u Requirements –Representative & away from obstacles u Historical Wind Observations –Tower of Winds in Greece (1 st Century BC) (Boreas - the north wind, etc.) –Maritime experiences (Doldrums, trade winds, etc.) –Beaufort Wind Force Scale

36. ATM OCN 100 Summer 2002 35 BEAUFORT WIND FORCE SCALE [Modern version, Source: Federal Meteorological Handbook I]

37. ATM OCN 100 Summer 2002 36 BEAUFORT WIND FORCE SCALE (con’t.)

38. ATM OCN 100 Summer 2002 37 SEA STATE For Calm Conditions (Force 0) Source: NWSFO Milwaukee

39. ATM OCN 100 Summer 2002 38 SEA STATE For Strong Breeze Conditions (Force 6) Source: NWSFO Milwaukee

40. ATM OCN 100 Summer 2002 39 SEA STATE For Hurricane Conditions (Force 12) Source: NWSFO Milwaukee

41. ATM OCN 100 Summer 2002 40 Windsock

42. 41 B. ANEMOMETRY (con’t.) u Modern Wind Observation Techniques –Surface (within 10 meters of surface) –Aloft (altitudes above 10 meters) u Modern Wind Instruments –For Direct Surface Observations F Anemometer F Wind Vane

43. ATM OCN 100 Summer 2002 42 ASOS Wind Instruments Wind Vane (left) & Cup Anemometer (right)

44. ATM OCN 100 Summer 2002 43 Aerovane Measures wind speed & direction

45. ATM OCN 100 Summer 2002 44 B. ANEMOMETRY (con’t.) u Modern Wind Instruments –For Direct Surface Observations F Anemometer F Wind Vane –For Indirect wind measurements aloft (Kites, radiosondes, radar, satellites)

46. ATM OCN 100 Summer 2002 45 B. ANEMOMETRY (con’t.) u Modern Wind Instruments –For Direct Surface Observations F Anemometer F Wind Vane –For Indirect wind measurements aloft to include…

47. ATM OCN 100 Summer 2002 46 Kites

48. 47 Pilot Balloons

49. ATM OCN 100 Summer 2002 48 Radiosonde

50. 49 Green Bay Radiosonde Sounding – Tues. PM. Tropopause Jet Stream

51. ATM OCN 100 Summer 2002 50 Upper Tropospheric Jet Stream – Tues. PM 300 mb Level or 9500 m altitude

52. ATM OCN 100 Summer 2002 51 Doppler Weather Radar See Pg. 344-351 Moran & Morgan (1997)

53. ATM OCN 100 Summer 2002 52 Example of Doppler Radar Displays during Tornado Event Oklahoma City 3 May 1999

54. ATM OCN 100 Summer 2002 53 Wind Profiler (FSL) See Pg. 352 Moran & Morgan (1997)

55. ATM OCN 100 Summer 2002 54 Recent 24-hr Wind Profiler Data: Blue River, WI

56. ATM OCN 100 Summer 2002 55 Wind Profilers

57. ATM OCN 100 Summer 2002 56 Satellite Derived Winds Aloft [SSEC]

58. ATM OCN 100 Summer 2002 57 C. SCALES OF ATMOSPHERIC MOTION u Importance of Scale u The Scales: –Planetary Scale –Macro or Synoptic Scale –Meso Scale - Organized Turbulence –Micro Scale - Turbulence or specifically....

59. ATM OCN 100 Summer 2002 58 C. CHARACTERISTIC SCALES of ATMOSPHERIC MOTION u Importance of Scale u The Scales (from Table 9.2, Moran & Morgan) : u Scale Interaction

60. ATM OCN 100 Summer 2002 59 Atmospheric Scales (from the Weather Doctor)