Climate and Global Change Notes

3-1

Upper-air Measurements

Radiosonde Rawinsonde

Science Concepts

Observing Climate - Upper Air

Climate and Global Change Notes

3-2

QuickTime™ and aTIFF (LZW) decompressor

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Observing Climate - Upper Air

U.S. Upper-Air Observations

Radiosonde Movie

http://www.nws.noaa.gov/om/educ/radiosnd.rm

Climate and Global Change Notes

3-3

Observing Climate - Upper Air

U.S. Upper-Air Observations

• Radiosonde instrument package

- Pressure- Temperature- Relative Humidity

• Rawinsonde - Trackedradiosonde

- Winds

http://www.ua.nws.noaa.gov/

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Climate and Global Change Notes

3-4

Observing Climate - Upper Air

Radiosonde

• 2 m (6 ft) wide hydrogen or helium filled balloon filled

• Rises at about 300 m/min (about 1,000 ft/min)

• Tracking positionyields wind speed and direction - called a rawinsonde. New system will use GPS

• Flight can last more than 2 h

• Can ascend to over 35 km (about 115,000 ft) and drift more than 200 km (about 125 miles)

http://www-das.uwyo.edu/~geerts/cwx/notes/chap07/hodo.html

Shipley, S.T, 2005: GIS applications in meteorology - Or adventures in a parallel

universe. Bull. Amer. Meteor. Soc., 86, 171-173..

Note drift distance during sonde’s flight, especially in regions of high

speed winds denoted by red shading (Isotachs - Contour of

wind speed)

Climate and Global Change Notes

3-5

Observing Climate - Upper Air

Radiosonde

• When the balloon expands too large (about 6 m or 20 ft in diameter), it bursts and a small parachute slows the descent minimizing the danger to lives and property

• Data (temperature, dewpoint temperature, and wind speed and direction) is plotted on a graph (Skew-T Log-p diagram) depicting the sounding versuspressure

http://www-das.uwyo.edu/~geerts/cwx/notes/chap07/hodo.html

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Temperature

DewpointTemperature

Winds

Climate and Global Change Notes

3-6

Observing Climate - Upper Air

U.S. Upper-Air Sites

http://www.ua.nws.noaa.gov/nws_upper.htm

Climate and Global Change Notes

3-7

Observing Climate - Observing Site

Balloon Inflation Shelterwith Radiotheodolite

radome

Rain GageInstrument

Shelter

CupAnemometer

Wind Vane

InstrumentTower

http://www.ua.nws.noaa.gov/

Typical WeatherService Observing Site