What is the role of deforestation in climate change and how can 'Reducing Emissions from Deforestation and Degradation' (REDD+) help?

How does deforestation contribute to climate change? 

Deforestation refers to the purposeful clearing or thinning of trees and forests. When deforestation occurs, much of the carbon stored by trees is released back into the atmosphere as carbon dioxide, which contributes to climate change. Land use change, principally deforestation, contributes 13–21% of global greenhouse gas emissions. Forest degradation (changes that negatively affect a forest’s structure or function but that do not decrease its area), and the destruction of tropical peatlands, also contribute to these emissions.  

As a result of deforestation and degradation, some tropical forests now emit more carbon than they capture, turning them from a carbon ‘sink’ into a carbon source. For example, the south-eastern part of the Amazon Rainforest is now considered a net carbon source by scientists. Due to drought and unusually high temperatures in 2023 (1.5°C above typical levels from 1991 to 2020), the entire Amazon rainforest became a ‘weak source’ of CO₂ emissions in 2023. It is too early to know whether this occurrence will continue into the future, as the carbon balance of the Amazon rainforest is contingent on net growth (total growth and carbon uptake minus deforestation) and climatic factors. However, the shift to a net source in 2023 should serve as a warning to conserve and restore the Amazon rainforest through policies like REDD+ . 

What are the drivers and scale of deforestation?  

The most important driver of deforestation is the global demand for agricultural commodities: agribusinesses clear huge tracts of forest and use the land to plant high-value cash crops like palm oil and soya, and for cattle ranching. Other human activities causing deforestation include urbanisation and infrastructure development, and over-exploitation of wood resources. 

In the last decade, the largest amounts of deforestation occurred across the humid tropics, mostly in Africa, followed by South America. The UN Food and Agriculture Organisation (FAO) estimates that around 489 million hectares of forest were lost between 1990 and 2025. The annual rate of loss slowed during that time but was still high at 10.9 million hectares per year between 2015 and 2025. The FAO calculates that the net change in forest area (which takes into account deforestation, afforestation and the natural expansion of forests) over this period was a loss of 4.1 million hectares.  

How can ‘REDD+’ help protect forests? 

Scientists have recognised the value of protecting forests in tackling climate change. Forest preservation is also crucial for protecting biodiversity. In response, policymakers have developed a family of policies – collectively known as ‘reducing emissions from deforestation and degradation’ (REDD) – to provide a financial incentive to governments, agribusinesses and communities to maintain and possibly increase, rather than reduce, forest cover.  

The plus in ‘REDD+’ refers to the role of conservation, sustainable management of forests and enhancement of forest carbon stocks in developing countries. Under REDD+, incentives for forest protection are offered to countries, communities and individual landowners in exchange for slowing deforestation, and carrying out activities that promote reforestation and sustainable forest management. Where local people are properly involved in the REDD+ process it may also help alleviate rural poverty. The principles of REDD+ were further reinforced in the Paris Agreement on climate change. 

REDD+ policies operate through a variety of mechanisms, including those administered by the United Nations (UN-REDD) and the World Bank (the Forest Carbon Partnership Facility). REDD+ finance is also considered in the international climate change negotiations, remains a key component of international climate finance discussions, and is often channelled through the voluntary carbon markets and via activities implemented by for- and non-profit organisations. 

How fair, effective and efficient is REDD+? 

While experts have demonstrated how REDD+ has the potential to reduce CO₂ emissions, it is not without its problems. For example, some question the fairness of a scheme that focuses on reducing emissions caused by some of the world’s poorest people while emissions continue to rise in richer countries. Some emerging markets and developing countriesmay be wary of foreign interference in their land use policies. Researchers also highlight operational concerns – such as the difficulty in monitoring and measuring deforestation rates, or attributing changes in deforestation to REDD+ finance. Variations in local circumstances and institutional capacities mean that not all countries that have tropical forests possess the capabilities to address these challenges. 

How much REDD+ finance has been pledged? 

Estimates of the global cost of REDD+ vary greatly, but at least US$20–72 billion is needed per year by 2030 to meet forest-based climate change mitigation targets under the United Nations Framework Convention on Climate Change (UNFCCC) – which includes reducing tropical deforestation and reforestation. According to a 2025 review, in 2024 US$341 million was approved through REDD+, compared with an annual average of US$203 million between 2024 and 2019 – an improvement, but also an indication that funding remains orders of magnitude off of the levels required. The Forest Carbon Partnership Facility (FCPF) has surpassed the Amazon Fund as the largest REDD+ fund, with US$1 billion allocatedacross 61 projects. 

Without sufficient finance, it can be difficult to protect forests, as alternative land uses (such as for palm oil) can offer more immediate and guaranteed cash returns. Consequently, many experts have called for a scaling up of commitments and finance flows, although some have argued that even if large-scale REDD+ finance does materialise it may still struggle to compete with other land uses – especially as and when commodity prices rise. 

The Tropical Forest Forever Facility (TFFF), launched in 2025 at the UN climate conference COP30 in Belém, Brazil, offers another route to incentivise countries to protect standing forests. While REDD+ rewards verified emissions reductions, the TFFF operates a ‘payment-for-performance’ model by rewarding countries in the tropics for each hectare of forest that remains standing, with penalties for deforestation exceeding 0.5% per annum and fire-related degradation using agreed remote sensing standards. 

Experts agree that REDD+ should focus first on areas that can most efficiently provide CO₂ reductions (such as tropical peat swamp forests) while also offering the potential for biodiversity conservation and poverty alleviation. 

This Explainer was last updated in March 2026 by Leo Mercer. The original was reproduced from: What’s REDD and will it help tackle climate change?, a collaboration between the Grantham Research Institute and the Guardian, © The Guardian 2012, used under a Creative Commons No Derivative Works licence.