MeteoFrance is collaborating with EMADDC and the French Air Traffic Control (DSNA) to establish a radar data stream to EMADDC. Following the update deployed this morning, observations generated from this dataset are now available under the source designation "fr-dsna, with a provisional test status, which we hope will soon be fully and officially operational.
Later this week, observations derived from data collected by FMI's receiver network will be made available in the production environment at ftpservice.knmi.nl. Currently, this data can be accessed through the acceptance environment at ftppro.knmi.nl. This dataset has been designated as "fi".
In addition to new data, two existing datastreams have been updated. The "uk" datastream has been improved to integrate data from the entire MetOffice receiver network into a single file, while also incorporating additional receivers. Previously, data from only nine receivers was transmitted to EMADDC; the new stream now accommodates data from fourteen receivers, thereby improving redundancy and coverage marginally. EMADDC benefits from receiving data in a single file, which significantly enhances processing and ingestion performance, reducing the time from 1.5 minutes to 10 seconds. Furthermore, the updated decoding and combining process is better equipped to identify duplicate messages, resulting in a reduction of duplication in EMADDC's processing system.
The French receiver data stream has undergone a similar update to consolidate all receiver data into a single file. This enhancement also improves system performance and reduces data duplication. Please be advised that with the integration of fr-dsna data, observations from "fr-dsna" will take precedence over French receiver data when identifyin duplicates. Consequently, we anticipate a greater volume of fr-dsna data in the published output of EMADDC's processing compared to "fr" data.
The changes made todady also include a recent software update has been implemented to enhance the decoding of positional messages derived from ADS-B information. This update introduces a check on the reported positional accuracy of the aircraft. Previously, all messages were accepted; however, we now discard messages that indicate an uncertainty of 0.25 nautical miles or greater in horizontal positioning. The outcome of this update is improved positional information in the observations derived from receiver data streams, though it has resulted in a slight decrease in data volume. Notably, data over Israel has been affected by this update, likely due to GPS jamming in that region.
Please be advised that all changes, including the system updates on the AWS platform, have undergone extensive testing over the past several months. Data collected from this system following the updates has been made accessible to users since July 2024 via ftppro.knmi.nl. EMADDC is confident that these changes will not adversely affect the quality of the produced observations, but rather enhance quality and data coverage.
Starting tomorrow, September 25, 2024, quality reports and coverage plots from the new operational systems will be available here.