As part of a recent Global Carbon Project methane budget activity funded by the Moore Foundation, we are organizing the collection and aggregation of global CH4 data from the flux tower community in coordination with the regional networks and FLUXNET initiatives. We aim to use this database for a global synthesis of CH4 flux tower data. By analyzing continuous, ecosystem-scale flux measurements, our synthesis should provide novel insights into the controls and timing of wetland CH4 emissions. We also plan to apply machine learning algorithms to upscale site-level fluxes to develop a new globally gridded methane product, analogous to what has been done previously for CO2. This gridded product will provide an entirely independent estimate of global CH4 emissions to compare with process-based models and atmospheric inversions.
To date, we have been working with a subset of sites measuring CH4 to assess the feasibility of this project. Last May we hosted a workshop in Washington DC with the PIs of these sites and representatives from AmeriFlux, EuroFlux and FLUXNET to: 1) Address issues of data limitations, consistency, and standardization & long-term steps needed to integrate methane in future FLUXNET releases. 2) Determine the best statistical approaches for developing gridded methane products. 3) Identify knowledge gaps, key research questions, and opportunities for new synthesis activities and collaborations.
Following this workshop, we would like to invite the entire flux community to participate in this multiyear synthesis activity. To facilitate the inclusion of CH4 fluxes in FLUXNET and develop a consensus regarding authorship and data policies, prior to the official data call, we would like your input on three brief questions: