Forest GHG removals

Forest carbon removals from the atmosphere, which we refer to as sequestration, represent the total carbon captured in megagrams of CO2 per hectare through the growth of both established and newly regenerating forests throughout the modeling period spanning from 2001 to 2021. These removals encompass the accumulation of carbon in both aboveground and belowground live tree biomass. In accordance with IPCC Tier 1 assumptions for forests that remain as forests, no removals are assumed for dead wood, litter, and soil carbon pools. The calculation of carbon removals for each geographical pixel adheres to the IPCC Guidelines for national greenhouse gas inventories. This calculation applies to areas where forests were present in the year 2000 or were established between 2000 and 2012, as indicated by the tree cover loss data provided by Hansen et al. in 2013.

The amount of carbon removed by each pixel is determined based on various factors, including the type of forest (e.g., mangrove, plantation), the ecozone (e.g., humid Neotropics), the age of the forest (e.g., primary, old secondary), and the number of years over which carbon removal has occurred. This layer represents the cumulative removals throughout the modeling period, which spans from 2001 to 2021. To obtain the annual average removal rate for the modeling duration, this cumulative value must be divided by 21, as removal rates cannot be allocated to individual years within the model.

Harris, N.L., Gibbs, D.A., Baccini, A. et al. Global maps of twenty-first century forest carbon fluxes. Nat. Clim. Chang. 11, 234–240 (2021).