The 2025 CEOS Strategic Implementation Team (SIT) Technical Workshop was held in Darmstadt, Germany on 9-11 September. The meeting was organized by the Japan Aerospace Exploration Agency (JAXA) as the SIT Chair and hosted by the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT).
Approximately 90 participants (60 in person and 30 online) attended the two-day hybrid meeting and side events held the day before. The workshop provided an opportunity to discuss strategic and technical issues and to prepare for decision-making at the CEOS Plenary in November.
Participants to 2025 SIT Technical Workshop in Darmstadt, Germany
Importantly, it was a valuable opportunity to discuss the two SIT Chair priorities – (1) Earth Observation Data Impact and (2) Atmospheric Observations, which JAXA committed to when it assumed the SIT chairmanship in November 2023.
Earth Observation Data Impact
As a core activity of this priority, the SIT Chair team presented the draft CEOS Global Stocktake (GST) Strategy Issue 2 which JAXA committed to leading an update of at the SIT-40 meeting in Fukuoka, Japan, in April 2025. The previous strategy developed in 2021 focused on opportunities and requirements related to the first Global Stocktake, and this Issue 2 was updated following reflection upon the implementation of the first version, incorporating findings from the GST Lessons Learned study compiled by the Working Group on Climate. The strategy also sought to accommodate a changing landscape and expand and balance the focus to mitigation, adaptation, and means of implementation. Issue 2 contained six recommendations for mitigation and eight recommendations for adaptation. Some of these recommendations are also expected to be advanced under the incoming 2026 CEOS Chair themes, one of which focuses on adaptation and resilience.
In addition to the GST Strategy, the meeting also discussed collaboration with key stakeholders in the field of climate change, such as UNFCCC and IPCC. Specific engagement streams and points of contact with UNFCCC were confirmed for the GST, adaptation, loss and damage, mitigation, capacity building, technology, transparency and GHG inventories, and climate finance. The SIT Chair Team also shared its efforts to strengthen strategic collaboration with the IPCC. Throughout its term as SIT Chair, JAXA has been working with the Task Force on National Greenhouse Gas Inventories (TFI) to explore ways to increase the reference and adoption of satellite data in IPCC agreed practices.
Atmospheric Observations
The GHG Task Team under the CEOS/CGMS WGClimate provided an update on the status of activities following the GHG Roadmap, which was endorsed in 2024. As the Roadmap focuses on the co-development of fit-for-purpose products in collaboration with stakeholders, GHG-TT shared its engagement status with key stakeholders, including the International Methane Emissions Observatory (IMEO) and the Global Greenhouse Gas Watch (G3W) of WMO.
The GHG-TT, under the lead of Yasjka Meijer of ESA, has taken action to revitalize IMEO’s working groups, including by taking the lead of the Use Cases WG. The meeting discussed that the next step for IMEO collaboration includes proceeding with the Use Case WG to develop initial use cases. The GHG-TT is also developing a controlled release database for addition to ceos.org/ghg which will provide satellite operators and scientists references of methane controlled release experiments, such that the maximum benefit can be obtained from these events.
Another important activity under the second priority is developing “Common Practices for Quantifying Methane Emissions from Plumes Detected by Remote Sensing” which was endorsed in August 2025. The document provides common practices for reporting facility-scale methane emissions. These practices are necessary to inform data producers of user expectations and to create trust in data. The meeting discussed promoting and adopting these practices through engagement with key partners, including IMEO, the Climate and Clean Air Coalition (CCAC), and Global Methane Pledge Champions. This activity has been a joint priority of the United Kingdom Space Agency (UKSA) during their term as CEOS Chair.
In addition to the priorities, the meeting addressed other very important issues, including the implementation of the CEOS AFOLU Roadmap, the CEOS Interoperability Handbook v2.0, and the Biodiversity Virtual Constellation. You can find more information on the meeting page of CEOS website.
The JAXA SIT Chair team would like to thank the CEOS members who participated in the 2025 SIT Technical Workshop for their valuable contributions and discussions. This meeting was a fruitful and crucial opportunity to set the stage for key decisions at the 2025 CEOS Plenary and to consolidate the achievements of JAXA’s SIT Chair term. The team would also like to express the deepest gratitude to EUMETSAT for hosting this wonderful meeting.
Hironori Maejima
CEOS SIT Chair and JAXA SIT Chair team
