The Committee on Earth Observing Satellites (CEOS) released the report “A Constellation Architecture For Monitoring Carbon Dioxide And Methane From Space” in October 2018. As stated in the executive summary, the report describes "a global architecture for monitoring atmospheric CO2 and CH4 concentrations and their natural and anthropogenic fluxes from space to (i) reduce uncertainty of national emission inventory reporting, identify additional emission reduction opportunities and provide nations with timely and quantified guidance on progress towards their emission reduction strategies and pledges (NDCs); and (ii) track changes in the natural carbon cycle caused by human activities and climate variations.” This approach is based on recent advances in space-based remote sensing methods that are able to augment the spatial and temporal resolution and coverage of the ground-based GHG network.
The report recommends a three-step implementation plan to achieve its objectives and recognizes the WMO IG3IS as being a critical and central piece of their plan:
1) Link the atmospheric GHG measurement and modeling communities and stakeholders in the national inventory and policy communities (through UNFCCC/SBSTA), to refine requirements;
2) 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 surface and airborne measurements of CO2 and CH4 with those from available and planned space-based sensors to develop a prototype, global atmospheric CO2 and CH4 flux product in time to support inventory builders in their development of GHG emission inventories for the 2023 global stocktake; and
3) Use the lessons learned from this prototype product to facilitate the implementation of a complete, operational, space-based constellation architecture with the capabilities needed to quantify atmospheric CO2 and CH4 concentrations that can serve as a complementary system for estimating NDCs in time to support the 2028 global Stocktake.