AOSC 200 Lecture Notes - Lecture 2: Emergency Position-Indicating Radiobeacon Station, Radio Propagation, Radiosonde
15 Feb 2018
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Document Summary
Temperatures can also be measured remotely using infrared sensors (radiometers). The radiosonde is a small instrument package suspended below a balloon lled with hydrogen or helium. As the radiosonde rises (300 meters/minute), sensors on the radiosonde measure pro les of pressure, temperature, and relative humidity; they are linked to a battery powered transmitter that sends the measurements to a ground receiver. By tracking the position of the radiosonde in ight, information on wind speed and direction aloft is also obtained. Observations where winds aloft are also obtained are called. The ight can last two hours, and the radiosonde can ascend to over 35 km and drift more than 200 km from the release point. During the ight, the radiosonde is exposed to temperatures as cold as -130 f (-92 c) and an air pressure only a few thousandths of what is found on the earth"s surface.
