Africa's Forests Now Emit Carbon Instead of Absorbing It

Between 2007 and 2010, Africa's forests were still doing what forests are supposed to do: pulling carbon out of the atmosphere and locking it away in wood, roots, and leaves. Then, according to a study published in Scientific Reports, a reversal began. By the time the researchers' satellite record ended in 2017, the continent's forests had crossed one of the most consequential thresholds in climate science — switching from a net carbon absorber to a net carbon emitter. The scale of the shift, approximately 106 million tonnes of forest biomass lost each year, makes Africa's forests the latest casualty in a pattern that has already claimed the Amazon and Southeast Asia's tropical canopies.

The study lands at a moment when the world's remaining tropical forests are under more scrutiny than ever. If the largest forested regions on three continents are now releasing stored carbon rather than absorbing it, the arithmetic behind global climate pledges becomes considerably harder.

What the Satellites Revealed

The research, led by the National Centre for Earth Observation at the Universities of Leicester, Sheffield, and Edinburgh, represents the most spatially detailed map of biomass changes across Africa produced to date. The team combined data from NASA's GEDI spaceborne laser instrument and Japan's ALOS radar satellites with machine learning techniques and thousands of ground-based forest measurements, producing a resolution fine enough to capture local deforestation patterns across the entire continent over a full decade.

The results split cleanly into two periods. During the first phase, from 2007 to 2010, African forests were accumulating biomass — absorbing carbon and growing. After 2010, the trajectory reversed. Tropical moist broadleaf forests, concentrated in the Congo Basin, Madagascar, and parts of West Africa, began losing biomass at rates that overwhelmed any gains occurring elsewhere on the continent.

Some savanna regions did show biomass increases during the study period, likely driven by shrub encroachment into grasslands. But these gains were far too small to offset the losses in tropical forests. The net result: Africa's forests as a whole became a source of atmospheric carbon, not a sink.

The weight of material lost each year is difficult to visualize at continental scale. The researchers offered a comparison: the annual biomass loss was roughly equivalent to the weight of 106 million cars.

The Congo Basin: Where the Losses Concentrate

The Democratic Republic of Congo sits at the center of this story. The country holds more than half of the Congo Basin's rainforest — the second-largest tropical forest system on Earth after the Amazon — and, according to WRI Africa, contributed more than three-quarters of the Congo Basin's total primary forest losses in 2024.

The drivers are multiple and reinforcing. Smallholder agriculture dominates, with subsistence farming responsible for the vast majority of forest clearing in the region. Charcoal and fuelwood production adds further pressure: around 95 percent of the DRC's population relies on biomass for cooking and heating energy, creating a direct link between household energy poverty and forest loss that no conservation policy can ignore.

Commercial agriculture is accelerating the damage. DRC's cocoa production more than quadrupled between 2015 and 2023, with much of the expansion pushing into forested land. Artisanal mining, often informal and difficult to regulate, indirectly causes many times more deforestation than the direct footprint of the mines themselves, as roads, settlements, and supply chains radiate outward from extraction sites. Logging concessions contribute their own footprint: the majority of roads in Congo Basin forest areas are related to selective logging operations.

Madagascar tells a parallel story at smaller scale. Slash-and-burn farming and charcoal production continue to strip the island's remaining forests, which harbor extraordinary levels of biodiversity found nowhere else on Earth. West African nations including Ghana, Ivory Coast, and Nigeria face similar pressures, with cocoa and palm oil expansion driving clearing in forest frontier zones.

A Pattern Playing Out on Three Continents

Africa is not the first tropical forest region to make this transition. According to Yale E360, all three of the world's major tropical rainforest regions — South America's Amazon, Southeast Asia, and now Africa — have crossed the line from net carbon absorbers to net carbon emitters. Each region arrived at this threshold through somewhat different pathways: industrial-scale agriculture and fire in the Amazon, palm oil plantations and peatland drainage in Southeast Asia, and the combination of smallholder farming, charcoal production, and mining in Africa.

The convergence matters because global climate models have long relied on tropical forests as a counterweight to fossil fuel emissions. When climate scientists calculate how much additional emission reduction is needed to stay within the Paris Agreement's temperature targets, they factor in a certain amount of natural carbon absorption by forests. As each major tropical region flips from sink to source, that assumption erodes.

Professor Heiko Balzter, Director of the Institute for Environmental Futures at the University of Leicester and the study's senior author, framed the stakes directly: "If we are losing the tropical forests as one of the means of mitigating climate change, then we basically have to reduce our emissions of greenhouse gases from fossil fuel burning even faster to get to near-zero emissions," he told Carbon Credits.

Why the Reversal Happened When It Did

The timing of the reversal — the shift from gain to loss occurring around 2010 — reflects the intersection of several accelerating trends across the continent.

Population growth is fundamental. Sub-Saharan Africa's population has been growing faster than any other major region, increasing demand for agricultural land, fuelwood, and building materials. As rural populations expand, farming extends into previously intact forest at the frontier.

Economic development pressures compound the demographic trend. Rising global commodity prices for cocoa, palm oil, timber, and minerals created financial incentives for forest conversion throughout the 2010s. Infrastructure development — roads, in particular — opened previously inaccessible forest areas to settlement and extraction.

Governance gaps made these pressures harder to contain. Many of the countries experiencing the steepest forest losses have limited capacity to monitor remote forested areas, enforce logging regulations, or manage the expansion of artisanal mining. The DRC, which holds the lion's share of the continent's tropical forest, has faced decades of conflict and institutional instability that have undermined conservation enforcement.

Climate change itself is beginning to play a role. Increasing drought frequency and fire intensity in some African forest regions stress trees and reduce their carbon uptake even before they are cleared. In the Republic of Congo, primary forest loss jumped from roughly 24,000 to 62,000 hectares between 2023 and 2024, with approximately half driven by fires, according to WRI Africa, illustrating how climate feedback loops can accelerate forest decline independently of human land clearance.

What the Congo Basin Still Absorbs — and What It Stands to Lose

Despite the continent-wide shift to net emissions, the Congo Basin remains the largest intact tropical forest carbon sink on Earth. Between 2015 and 2024, the basin still removed an average of 160 million tonnes of carbon dioxide equivalent from the atmosphere each year — roughly equivalent to the annual fossil fuel emissions of Nigeria, according to WRI Africa.

But the trajectory is troubling. Primary forest loss in the Congo Basin increased by more than 14 percent in 2024 compared to 2023, with nearly 780,000 hectares cleared in a single year. If this acceleration continues, the Congo Basin's remaining absorptive capacity could erode within years rather than decades, removing one of the last major natural buffers against rising atmospheric carbon concentrations.

Approximately 100 million people depend on the Congo Basin's forests for food, medicine, shelter, and livelihoods. The forests regulate regional rainfall patterns, stabilize soils, and support river systems that are critical for agriculture and hydropower across central Africa. Forest loss does not only release carbon — it destabilizes the ecological infrastructure on which human communities depend.

The Response: Restoration Pledges and a New Financing Mechanism

The policy response to African deforestation has historically been underfunded relative to the scale of the problem. Two initiatives now aim to change that calculus.

The African Forest Landscape Restoration Initiative, known as AFR100, targets the restoration of 100 million hectares of degraded and deforested land across Africa by 2030. The initiative operates as a country-led, multi-stakeholder partnership, with dozens of African nations having made restoration pledges. Whether those pledges translate into planted trees and recovering ecosystems at the necessary pace remains an open question.

The Tropical Forests Forever Facility, launched at COP30 in Belém in November 2025, represents a fundamentally different approach. Rather than paying for restoration after the fact, the TFFF aims to pay tropical forest countries directly for each hectare of standing forest they maintain, with payments adjusted downward based on any deforestation detected by satellite monitoring. According to Yale E360, the facility aims to mobilize more than $100 billion, though actual pledges at COP30's conclusion stood at a fraction of that target.

Dr. Nezha Acil of the University of Leicester, one of the study's authors, pointed toward specific policy levers: "Stronger forest governance, enforcement against illegal logging, and large-scale restoration programs...can make a huge difference in reversing the damage done," she said in the study's press release.

What This Does Not Tell Us

The study's findings are robust for what they measure — changes in aboveground biomass across African biomes — but several important uncertainties remain.

First, the study period ends in 2017. The trend may have accelerated, stabilized, or shifted since then. Updated satellite analyses using more recent GEDI data will be needed to determine the current trajectory.

Second, the study measures aboveground biomass, not total ecosystem carbon. Belowground carbon stored in roots and soils, which can represent a substantial fraction of total forest carbon in some ecosystems, is not captured. The belowground carbon response to deforestation can lag the aboveground signal by years or decades, meaning the full carbon impact of the biomass losses documented here may not yet have materialized.

Third, while the study identifies tropical moist broadleaf forest loss as the dominant driver, it does not attribute the deforestation to specific causes at the pixel level. The drivers discussed above — agriculture, mining, charcoal, logging — are drawn from contextual research and regional analyses rather than from the biomass study itself.

Finally, the savanna biomass gains that partially offset tropical losses raise their own questions. Shrub encroachment into grasslands can represent a form of land degradation for pastoral communities even as it increases above-ground carbon stocks. Not all biomass gain is ecologically or socially beneficial.

The Arithmetic Gets Harder

The fundamental challenge revealed by this study is not biological but political. Africa's forests crossed from sink to source during a period when global climate policy was counting on them to do the opposite.

The Paris Agreement's nationally determined contributions, the carbon credit markets that fund some conservation efforts, and the climate models that project future warming pathways all incorporate assumptions about how much carbon forests will continue to absorb. When those assumptions fail — as they have now failed for all three major tropical forest regions — the remaining options for staying within temperature targets narrow to two: faster fossil fuel emission reductions, or acceptance of higher warming.

Balzter characterized the finding as "a critical wake-up call for global climate policy". The study makes the call quantitative: the amount of carbon that African forests were absorbing before 2010, and that they are now releasing, must be compensated for elsewhere in the global carbon budget if climate targets are to remain achievable.

The mechanisms to do this exist in principle. The TFFF could, at full scale, protect a billion hectares. AFR100 could restore a hundred million. REDD+ frameworks could channel carbon finance to forest-dependent communities. But each of these operates at a fraction of the scale required, and the deforestation clock is not waiting for funding commitments to close.

Key Takeaways

• Africa's forests crossed from carbon sink to carbon source after 2010, losing approximately 106 million tonnes of biomass annually between 2010 and 2017, according to a study in Scientific Reports.

• All three major tropical rainforest regions — the Amazon, Southeast Asia, and Africa — now emit more carbon than they absorb, eliminating a key assumption in global climate models.

• The Congo Basin remains the largest intact tropical carbon sink but is losing primary forest at an accelerating rate, with a more-than-14-percent increase in losses in 2024 compared to the prior year.

• Smallholder agriculture, charcoal production, mining, and logging are the primary drivers, compounded by population growth and governance gaps across forested nations.

• New financing mechanisms including the Tropical Forests Forever Facility and the AFR100 restoration initiative aim to reverse the trend, but current funding commitments remain far below the scale needed to protect the continent's remaining forests.