Processing Meteorological Data Acquired From Aircrafts With Mode-S Radars

Mode-S radars are capable to acquire meteorological data from aircrafts. At present it is possible to get temperature, wind speed and direction. The data are decoded, collected and stored. The Slovenian Environmental Agency provided control data from radiosondes. Radiosondes measure data daily and are valuable source of information about high atmosphere. Aircraft data were compared to radiosondes data and analysed for accuracy and reliability. The last part of paper describes methods for producing vertical atmosphere profile from data fetched from radar in real time with Kalman filter. The method presented automatically excludes measurements which are not accurate enough to get more accurate results. Data produced with this method were surprisingly accurate. Vertical profiles produced from aircraft data proved to be a very good substitute for radiosonde data. They are also much cheaper but they lack some information. Main drawbacks are missing air moisture data because aircrafts don't have sensors for it and missing data on heights where aircrafts don't fly. At least air moisture data can be expected in the near future since some sensors are already mounted on aircrafts for tests. There are many possible ways of usage of data acquired this way. AMDAR project could get a large amount of additional data via alternate path. With more information about atmosphere aircrafts could be warned about weather inconveniences. We are exploring other ways of using the data with Slovenian Environmental Agency and intend to develop new useful products