European University RadiOsonde Partnership (EUROP) during GARRP Demo 2027

What is EUROP?

EUROP is a collaborative network of European universities and weather services, that was initiated to support the NAWDIC field campaign in January and February 2026 (https://www.nawdic.kit.edu/196.php). The initiative aims to obtain additional radiosonde observations from several European locations to be assimilated directly into global weather forecasting systems, such as the ECMWF system. Thus, the effort has a direct impact on the quality of the numerical weather prediction (NWP). In addition to the scientific goals, EUROP aims to provide an exciting educational opportunity to involve students in an international field campaign. During the NAWDIC campaign in 2026, three universities and five weather services participated with more than 140 radiosonde launches during intensive observation periods (IOPs), supported by 30 student helpers in total. EUROP is paired with analogous partnerships connecting universities across North America (the AR Recon Coordinated University Sounding Program (CUSP)) and will emphasize the importance of radiosonde launches and meteorological observations for forecast quality and research activities.

Why coordinated radiosonde launches?

In January and February 2026, the three missions AR Recon (Atmospheric River Reconnaissance), NURTURE, and NAWDIC successfully demonstrated the possibility to carry out simultaneous measurement flights over the northern hemisphere, from the western Pacific to the eastern Atlantic. As part of the demonstration mission for the Global Atmospheric River Reconnaissance program (GARRP), the missions contribute to coordinated global AR investigations across ocean basins to improve forecast accuracy. The deployment of additional radiosondes complements this global setup with the aim of quantifying the added value that each observation would bring to the forecast quality. All radiosonde data, in addition to dropsondes from the various involved aircraft, are sent to the Global Telecommunication System (GTS) to be directly available for assimilation into global NWP models in real time. This allows to estimate the atmospheric state at time of forecast initialization more accurately and provides unique opportunities for data denial experiments following the campaigns.

What will participants in the partnership do?

During the campaign period in January and February 2027, participating universities and institutions will perform radiosonde launches coordinated with the campaign operations center. Launches will be requested two days in advance for meteorological standard times (00, 06, 12, 18 UTC) during IOPs, depending on the local capacities. Based on experience from last winter, we expect a total of not more than 20 launches per site. Universities are encouraged to involve student groups (e.g., forecasting/ instrumentation classes, etc.) to prepare and perform the launches. Therefore, in addition to the science goal of increasing land-based observations for forecast improvement, the project also includes an educational goal of student training in gathering observations with real-time impacts. We also encourage the lead faculty and students to virtually participate in daily weather briefings during the operational phase (exact times t.b.d.).

What do we offer to the participants?

Unfortunately, we will not be able to provide funding for this initiative, implying that university programs would need to cover the costs for the radiosonde launches and would also need to have access to their own radiosonde launching system. If you are aware of potential funding sources for such an initiative, please reach out to us!

On the technical side, we will help to register the launch site for the GTS (e.g. with a WIGOS identifier) and offer an SFTP server to transfer the data to the GTS. Also, if there are problems with writing data into the required BUFR format, we are very happy to assist. Furthermore, all participating institutions will be listed as project partners on the EUROP web page and acknowledged in peer reviewed related campaign articles.

What is beyond the European partnership?

This initiative has direct links to a corresponding initiative coordinated by AR Recon. A pilot project was successfully conducted in the U.S. with 9 participating universities launching 100 radiosondes. Here are some impressions:

“Students loved being involved in the launches, especially knowing the connection back to AR Recon.”

“The launches facilitated community engagement across campuses with involvement from faculty/staff across departments, and collected data was actively used by students in the classroom, highlighted by local broadcast stations, and incorporated into National Weather Service forecasts.”