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CAMEX-4 Andros Island Rawinsonde and Radiosondes Table of Contents
The Office of the Federal Coordinator for Meteorology has a page devoted to radiosondes and rawinsonde, and it is the source for much of the following information. The term radiosonde is a contraction for radio-sounding device. The instrument measures the ambient pressure, temperature, and moisture. When attached to a weather balloon filled with a lighter-than-air gas, radiosondes can attain heights in excess of 30 kilometers. Winds are determined from changes in the radiosonde position during the flight. The thermodynamic and wind data information are formulated into a "rawinsonde" observation. Principles of OperationThe radiosonde transmits its data to a ground-based telemetry system (antenna and receiver). This telemetry system receives the signals and forwards them to another module (signal processing system) to be decoded into meteorological units. Data are then passed to a computer for collection of data for the entire sounding and formulation of the observation products. When the balloon reaches it elastic limit and bursts, a parachute slows the descent of the radiosonde to the ground. The radiosondes used at Andros Island were GPS type radiosondes using full code-correlated transmission from up to 10 GPS satellites, providing accurate height and wind information allowing pressure/height correlations to be calculated. Data Naming Conventions and Data FormatAndros radiosonde data is archived into one composite tar file per day of the form:
Where ddd is the day of the year. When untarred, there will be files in ascii form representing the sonde data whose filenames are in the form:
where mm is month, dd is day and hhmmss is launch time in hours, minutes and seconds in UTC. Data is in the UAIRP uniform 10-second and standard pressure level data output file format. The UAIRP format is as shown here. Note information in this format concerning the type of sonde used for the sounding. To order these data or for further information, please contact:
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