Radiosondes

Radiosondes are self-contained meteorological instrument packages attached to weather balloons that measure atmospheric temperature, humidity, pressure, and wind as they ascend through the atmosphere. They transmit sensor data back to ground receivers in near real time, where the information is quality controlled and incorporated into weather analyses and forecasts. Radiosonde data provide high-vertical-resolution profiles essential for weather prediction, climate research, and atmospheric studies.

Operation and data collection: Each radiosonde is released from a forecast or observation station with a balloon; as the balloon rises, the onboard sensors log temperature, humidity, and pressure while the instrument also tracks wind by determining the balloon’s position, typically using GPS and radio triangulation. The package usually ascends to about 30 kilometers before the balloon bursts; the descended payload may descend by parachute and is frequently recovered for reuse, though some are not recovered.

Equipment and transmission: Modern radiosondes compactly house radios and sensors, transmitting data on dedicated radio frequencies to ground stations or satellites. Readings are archived and distributed to national meteorological services and international networks.

Uses and networks: Radiosonde data enter national and global observing systems and are shared through the WMO Global Telecommunication System. They are used to create vertical profiles of temperature, humidity, and wind that feed numerical weather prediction models and validate satellite observations. They also contribute to long-term climate records and atmospheric research.

History and variants: Radiosondes have been deployed since the early 20th century and remain a cornerstone of atmospheric observation. Multiple instrument packages exist, including commonly used models such as RS92 and RS41, produced by several manufacturers, with data formats standardized for international sharing.