Application of Earth Observation for regional carbon budget assessments

Here we present a summary of research conducted under the Regional Carbon Cycle and Processes Project phase 2 (RECCAP2-A) funded by the European Space Agency. Our aim was to optimally use Earth Observation data to improve regional carbon cycle assessments and reconcile across bottom-up, top-down and NGHGI methodologies. Results include the application of a new EO-based fire carbon emissions book-keeping model for the Brazilian Amazon and Cerrado biomes (REFIT.AC), and we show how emissions from deforestation and degradation vary with land management. We use satellite L-Band Vegetation Optical Depth (L-VOD) (0.25^o) data that provide an integrated (top-down) estimate of biomass carbon to track changes over 2011–2019. We combine high-resolution annual maps of forest cover and disturbances with biomass maps to model carbon losses from deforestation and degradation, and gains from regrowing secondary forests to enable process attribution of the coarse resolution L-VOD trends. We develop a space-for-time approach utilising EO-based biomass and age-since disturbance maps to estimate carbon loss from forest degradation and recovery across environmental gradients. The regrowth curves are applied in a book-keeping model to quantify carbon implications of forest restoration out to 2030. Finally, we present results of diagnostically applying EO-fire burnt area within fire-enabled Dynamic Global Vegetation models to improve estimates of fire carbon emissions.