Upper Observation is a key activity of operational Meteorology being the only source of in-situ measurements in the atmosphere.
These measurements are usually performed one or twice a day from meteorological sites distributed around the world, whether it deals with manual or automatic soundings.
The purpose of this kind of Observation is to produce and disseminate meteorological messages that are interpretable by forecasters. Thus, radiosondes feed Numerical Weather prediction models to establish weather forecast, early warnings…
Radiosonde systems are also crucial regarding Climatology, the science that focuses on describing and analyzing the climate change over long-term periods. That is the reason why accuracy and traceability of measurements remain of major importance.