2018 CEOS SIT Technical Workshop Minutes v1.0

- - Exploit the capabilities of the CEOS Member Agencies, Coordination Group on Meteorological Satellites (CGMS) and the WMO Integrated Global Greenhouse Gas Information System (IG3IS) to integrate available and planned space-based sensors into a constellation that can provide prototype space-based CO2 and CH4 product in time to inform the bottom-up inventories for the 2023 global stock take; and
- - Use the lessons learned from the development of this prototype product to refine the requirements for a future, purpose-built, operational, space-based constellation that more completely addresses the objectives cited above in time to support the 2028 global stock take.

The AC-VC GHG White Paper is complete and ready for review by the CEOS entities, and Dave offered one week to allow comments to the White Paper, and the next step will be to submit the final White Paper to CEOS Plenary. AC-VC supports the proposal to transfer the implementation responsibility to a (new) CO /CH subgroup within WGClimate, and will continue to support synergistic GHG and atmospheric 2 4 composition observations and modeling efforts. A brief discussion followed.

- - Steve stressed the importance of feedback on the White Paper within a week in order to meet the deadline for Plenary materials.
- - Carolin asked about the next steps following the finalization of the paper. David noted that the paper has been widely circulated, and engagement with the Inventory community has started and will be important.
- - Mark noted that this effort fits well with current WGClimate activities. He also noted that this document should be made available broadly, and the lack of ability for CEOS to provide an official citation for the document is a potential issue. John Remedios (UKSA) agreed, and noted that other international agencies can provide citations.
- - John noted the 2021 milestone is quite tight, and David noted that this is only achievable because it can leverage existing and ongoing activities. He also noted that engagement with the Inventory community will be key, and these can be built via links with the Scientific Inventory community and their connections to the operational Inventory community. David also noted that the product will not be perfect, but might be the best product available to developing countries in 2021.
- - Steve asked if the paper would presented for endorsement at the Plenary, and Mark noted they would like to push for endorsement but this should be discussed and agreed before the close of the Workshop, Kerry noted that it will be important to find the correct language for endorsement/acknowledgement at Plenary and agreed to review how previous CEOS reports were presented for endorsement.

#### IPCC Guidelines Osamu Ochiai (JAXA) provided an update on the IPCC Guidelines for National Greenhouse Gas Inventories:

- - The current status and timeline was shown; in the second order draft (SOD) there were some positive developments for EO data: small chapters and subheadings related to satellite observation are added; satellite retrievals are recognized to cover large areas of the atmospheric column; cited the projects

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