ECMWF has taken a world-leading role in the interpretation of observations from satellites. We now use data from more than 50 types of sensor, and are testing many more.

Observation types used in the forecast

Weather forecasts have always relied on accurate observations of the current weather. Modern numerical weather prediction is no different and makes extensive use of terrestrial and satellite observations. These observations provide atmospheric, ocean and land surface information. Satellites now provide most data, although more traditional observations are still important.

We contribute to the future development of the global observing system both through assessing the potential impact of new data and by pioneering the use of new satellite data, including data from research satellites such as those in the A-train and ESA’s Earth Explorer missions. The variety and quality of satellite observations is still changing rapidly, though some types are now very well established. Satellite instruments are very complex, often making many thousands of individual observations simultaneously at the same location, and requiring sophisticated techniques to interpret the information they contain. Observations, in particular from satellites, combined with improved earth-system modelling and advances in data assimilation techniques, make a major contribution to improve medium range weather forecast skill.