Safeguarding Forests for Future Stability: A Call to Preserve Global Carbon Stocks

The World Bank's report highlights the urgent need to protect global forests and ecosystems, as they play a critical role in carbon storage and climate resilience. With deforestation and land-use changes reducing carbon stocks, the report emphasizes carbon retention's economic value, guiding policymakers on sustainable land management.

The World Bank’s latest technical report, developed with contributions from the Basque Centre for Climate Change and the María de Maeztu Unit of Excellence, offers a comprehensive examination of global carbon stocks across vegetation and soil, spanning the years 2001 to 2020. Using the advanced ARIES platform (Artificial Intelligence for Environment and Sustainability), the report models the carbon stored in aboveground and belowground biomass and soils, providing a globally consistent methodology for quantifying terrestrial carbon stocks. This analysis, grounded in data from the European Space Agency Climate Change Initiative (ESA-CCI) and aligned with IPCC guidelines, underscores the vital role of ecosystems in regulating the global carbon cycle. Forests, which are identified as the most significant carbon reservoirs, especially in tropical regions, emerge as essential in combating climate change. However, the report reveals that deforestation and land-use changes, particularly in tropical regions like Brazil and the Democratic Republic of Congo, are driving an alarming trend in carbon stock declines, underscoring the urgency of ecosystem protection to support global climate resilience.

The Landscape of Carbon Storage: Forests Take the Lead

The ARIES-based model uses a variety of data, including ESA-CCI satellite imagery and global land cover classifications, to evaluate carbon stock across various land types, including forests, wetlands, shrublands, agricultural lands, and sparse vegetative cover. This extensive data integration allows for yearly carbon stock estimates, which reveal that forest ecosystems alone contribute over 70% of the world’s total vegetation carbon stocks, a much greater proportion than other land cover classes. Other major contributors include shrub and herbaceous vegetation (about 14%) and agricultural vegetation (around 9%). Despite forests’ prominent role, the report highlights an overall downward trend in vegetation carbon stocks, driven by persistent deforestation and land-use shifts. Forests in regions such as the Amazon and Congo basins, while globally critical as carbon sinks, are facing unprecedented pressures from agriculture, urban expansion, and illegal logging. The loss of these vital ecosystems not only reduces carbon storage capacity but also disrupts local biodiversity and ecosystem stability, worsening the effects of climate change.

Modeling the Carbon Picture with Advanced Data Integration

In its methodology, the ARIES model integrates multiple layers of data, such as land cover, eco floristic zones, and primary forest presence, to estimate carbon in aboveground and belowground biomass and soil organic carbon. Carbon density in vegetation varies significantly by region and forest type, with tropical and primary forests storing substantially more carbon than secondary or degraded forests. The report’s focus on country-level data enables a clearer understanding of global trends and provides actionable insights for policymakers. Brazil, which holds nearly 20% of the world’s vegetation carbon, illustrates this trend starkly: its forests experienced marked declines in carbon stock, mainly due to agricultural expansion. The Democratic Republic of Congo, the United States, and Russia are also among the countries with significant reductions in forest carbon, while countries such as Tanzania, Ethiopia, and the Philippines are noted for carbon stock increases, albeit on a smaller scale. Despite minor gains in shrub and herbaceous vegetation and agricultural carbon stocks, these increases are not sufficient to offset losses in forest carbon stocks, highlighting the unequal distribution of carbon storage potential across land types.

Valuing Retention: A New Approach to Carbon’s Economic Impact

The monetary valuation method adopted in the report is based on a novel “carbon retention” concept, developed during the SEEA EA revision process, that views stored carbon as a climate service. This approach departs from traditional carbon sequestration models, focusing instead on the economic value of avoiding carbon emissions by retaining stored carbon. By applying a social cost of carbon estimate of 33.70 dollars per tonne, the model calculates the economic implications of carbon stock losses and frames carbon retention as a critical asset for climate policy. This method provides policymakers with a clearer perspective on the benefits of ecosystem preservation for climate resilience, aligning with global efforts to reduce emissions. The report emphasizes that forests with higher carbon retention rates are invaluable, even when they reach near-equilibrium, where sequestration rates decline. It also provides a consistent monetary valuation framework, allowing direct comparisons across countries despite local environmental and economic differences.

Enhancing Accuracy: Planned Improvements and Data Refinements

To improve future carbon stock estimates, the report outlines several planned enhancements. The World Bank and ARIES team anticipate integrating the IPCC’s 2019 refinements and including more detailed information on forest aging and post-fire regrowth. As the ARIES model relies on default IPCC values for aboveground biomass, transitioning to updated factors would enhance accuracy in estimating national and subnational carbon stocks. Additional refinements aim to include uncertainty estimates per IPCC guidelines, providing a more transparent understanding of potential data limitations. Furthermore, advanced modeling of fire impacts and vegetation recovery rates would capture dynamic environmental processes more accurately, particularly in fire-prone areas. Given its foundation on globally comparable data, the report’s findings are instrumental in informing climate policy, emphasizing that carbon stock trends are useful indicators of environmental and land-use change.

A Call to Action: Protecting Carbon Stocks for Climate Resilience

The report contributes valuable insights into global carbon dynamics, presenting an evidence-based framework that underscores the urgency of protecting ecosystems to mitigate climate change. The World Bank’s work with ARIES showcases the importance of interdisciplinary approaches to environmental sustainability and provides critical tools for policymakers to strengthen climate resilience. Highlighting global carbon trends, it serves as a call to action for integrating carbon retention into national and international climate strategies. The analysis of vegetation carbon across ecosystems offers not only a baseline for monitoring but also actionable knowledge to guide resource allocation, policy formulation, and land-use planning aimed at achieving sustainable development goals and long-term ecological balance.