Model-observation handshake Research increasingly in the context of improving representation of coupled Earth system models – Improved process representation – Reduced uncertainty Supporting model-data fusion – Benefits of multiple data constraints – INFUSION model-data fusion activity Large number of participating sites/models Treatment of data for data assimilation (e.g. energy balance correction) Dealing with “dark data” (formats, units, accessibility) Data formats for BADM data (biological, ancillar, disturbance, metadata) List of priority variables needed for models, remote sensing calibration, and synthesis studies

Model-data fusion: More attention needed Needs to be more integral part of model development – Process complexity ≠ accuracy Many models have serious problems representing key carbon cycle variables Task is daunting, modelers need to start with simple methods – Component model calibration – Limit pre-processing – Easy for model to ingest Efforts needed (working group?) on refining assimilation-ready data products for global models – Bringing in “dark” data – Multi-scale, multi-variable – Integrated uncertainty estimates Courtesy Sasha Hararuk, Yiqi Luo

Variables of interest to modelers Vcmax – slope of light use efficiency curve Soil moisture profile Soil turn-over Soil heterogeneity Leaf to canopy scaling factor Characterization of light penetration inside canopy Soil carbon, biomass

Challenge: Translating Between Model Need Observation Capabilities Vcmax GPP LAI and Leaf nitrogen ??? Canopy Leaf Scaling Model-data fusion

Ideas Uncertainties should be provided where possible Add requirement that data be submitted in standard formats to funding calls Identify ways to make BADM easier for sites to provide AmeriFlux information request – Send top two data variables most needed from sites – send to along with an explanation of why they are