7.2 Weather Stations
In-situ measurements from surface stations, radiosondes, aircraft, and buoys provide ground truth for remote sensing and model initialization.
Surface Observations
- • Temperature, humidity, pressure
- • Wind speed and direction
- • Precipitation (rain gauge, weighing bucket)
- • Cloud cover, visibility, weather type
Radiosondes
Balloon-borne instruments measuring T, RH, p, and wind up to ~30 km. Launched twice daily (00Z, 12Z) worldwide.
~900
Stations globally
5 m/s
Rise rate
~90 min
Flight duration