Early Upper Air Information (late 1800s, early 1900s)

1. Upper Air DataThe Atmosphere is 3D and can not be understood or forecast by using surface data alone

2. Early Upper Air Information(late 1800s, early 1900s) • Mountain weather stations • Manned balloons

3. Early Upper Air Information(late 1800s, early 1900s) • Weather kites

4. Weather Kite

5. Early Upper Air Observations • Manned aircraft observations (1905-1940) • Problem: could not fly in stormy weather • Didn’t go that high

6. Navy bi-plane with meteorgraph on starboard wing strut, taking meteorological measurements for pressure, temperature, and humidity

7. Tracking Balloons Was Used to Secure Winds in the early 20th Century (still used in some locations)

8. Pilot Balloons (PIBALS) Provided Winds Aloft

9. The Big Breakthrough: The Radiosonde • A radiosonde is a portable weather station lofted by a balloon. • Sends observations back by radio. • The first instrument launched on January 7, 1929.

11. Rapid Expansion of the Upper Air Network During the 1930s and 1940s.

13. Modern Radiosondes

14. Radiosonde

16. Generally twice a day at 00 and 12 UTC

17. Radiosonde believe it or not… A typical NWS "weather balloon" sounding can last in excess of two hours. In that time, the radiosonde can ascend to an altitude exceeding 35 km (about 115,000 feet) and drift more than 300 km (about 180 miles) from the release point. Typical pressure at balloon burst about 5 hPa (1/200th of surface pressure).

18. Radiosonde Video http://www.youtube.com/watch?v=jGQWUFEMxT8 Cam on radiosonde https://www.youtube.com/watch?v=pCve1w1GFOs Full flight: https://www.youtube.com/watch?v=xkFsy-u3dDo https://www.youtube.com/watch?v=9CjjbauSvBE

19. ACARS: Aircraft Observations Aircraft Communications Addressing and ReportingSystem

22. Remote Sensing of Upper Atmosphere

23. Radar Wind Profiler

24. Radar Wind Profiler and RASS (Radio Acoustic Sounding System)

25. Seattle Profiler/RASS

26. Satellite Data Geostationary and Polar Orbiting Satellites

28. Cloud and Water Vapor Track Winds Based on Geostationary Weather Satellites

30. GOES sounder unit

32. Satellite Temperature and Humidity Soundings

33. GPS Sounding • A constellation of GPS satellites orbit the earth. • A collection of other satellites can receive the GPS signal • By measuring the delay in time as the GPS signal is bent by the earth’s atmosphere, one can acquire density information that can be used to create temperature and humidity soundings. • Can do this with fixed receivers on earth or with receivers on satellites--the COSMIC project.

36. Upper Level Chart

37. Upper Level Maps • Meteorologists use upper level charts that describe atmospheric structure aloft. • They have one major difference with surface charts • Surface charts give pressure at a constant height • Upper air charts give the height of a pressure surface above sea level.

38. Like a topographic map

40. Upper Level Charts Give the Heights of Constant Pressure LevelsEssentially how the pressure level undulates in 3D space • Typical levels include: • 850 hPa ~5000 ft, 1.5 km ASL • 700 hPa ~10,000 ft, 3 km ASL • 500 hPa ~18,000 ft, 5.5 km ASL • 250 hPa ~34,000 ft, 10.5 km ASL

42. Upper level charts • Heights in meters (solid lines) • Temperatures in Celcius/Centigrade (C)-dashed lines. • Upper air station model (a bit different than surface one)