Forest carbon accounting has a documented blind spot: damage that falls short of complete clearance can still release substantial amounts of carbon, yet degradation and recovery are not always represented consistently in models or national inventories. An ESA report on a new meta-analysis says the distinction matters for understanding tropical forests and for measuring progress under the Paris Agreement.
The review examined evidence from 146 peer-reviewed studies published between 1988 and January 2026. It focused on tropical moist forests, which grow in regions with high annual rainfall and a marked dry season. According to the ESA report, these forests hold roughly 70% of the carbon stored in the world’s living vegetation.
Partial damage can carry a large carbon cost
Complete deforestation is comparatively well understood: trees are removed, the stored carbon is disturbed and the land changes use. Forest degradation is more difficult to capture. Selective logging, wildfire, wind damage and drying at forest edges can reduce the condition of a forest without removing every tree. The resulting carbon losses may be dispersed across time and space, making them harder to measure and easier to omit from large-scale accounting.
The review found marked differences between disturbed and undisturbed forests. Forest fires were associated with almost 50% more carbon release than undisturbed forest conditions. Selective logging was linked to 34% more carbon release, while damage at forest edges caused by wind and drier air was associated with 31% more carbon loss. These figures describe the relationships identified across the reviewed evidence; they are not a universal estimate for every forest or every fire.
The findings also show why carbon accounting cannot stop at measuring loss. Partially damaged forests retained more of their carbon and recovered more strongly than forests regrowing after complete clearance. After 20 years, partially damaged forests held an average of 75% of the carbon found in undisturbed forest. Forests that regrew from fully cleared land held about 38% by comparison.
The difference reflects what survives partial disturbance: seeds, soil, roots and remaining tree material can support recovery. Location matters as well. A degraded forest next to healthy forest has better access to seeds, increasing the possibility of natural regeneration. That does not make degradation harmless, but it changes the trajectory that models and inventories need to represent.
Why the distinction matters for national reporting
Countries use forest carbon estimates in greenhouse-gas inventories and in assessments linked to the Paris Agreement’s Global Stocktake. If degradation is treated as complete deforestation, or if recovery is not recorded separately, the resulting figures can misstate both emissions and removals. The ESA report says the review offers a comparable framework that countries can use when deciding which emission and removal factors are appropriate.
This is a measurement issue as much as a policy issue. A forest can remain standing in satellite imagery while losing biomass through repeated fires, selective logging or edge effects. Conversely, a recovering forest can regain carbon without returning immediately to the structure or storage capacity of an undisturbed forest. Separating those pathways gives inventories a better chance of describing what is happening on the ground.
Satellites are helping close the measurement gap
Earth observation has made the distinction easier to investigate. The ESA report says advances since around 2015 have improved the ability to distinguish degradation from deforestation and to follow recovery over time. ESA’s Climate Change Initiative Biomass project has contributed openly available global maps of above-ground biomass at 100-metre resolution, drawing on observations from Copernicus Sentinel-1, Japan’s ALOS-2 PALSAR-2 and NASA’s GEDI lidar mission.
Those datasets do not replace field observations. Instead, the review describes a growing combination of ground-based, airborne and satellite measurements. Together, they can provide wider coverage while helping researchers test whether observed changes reflect fire, logging, fragmentation, natural recovery or other processes.
The accompanying official ESA Biomass image shows a radar view of forest and landscape in Bolivia. It illustrates the type of Earth-observation context behind this work, but it is not presented as a visual measurement of the meta-analysis results.
A clearer picture of forest change
The review does not suggest that every degraded forest follows the same recovery path, nor that satellite data can remove all uncertainty. Its importance is more precise: carbon reporting needs to account for the different ways forests lose and regain biomass. Fires, selective logging and edge damage can have distinct effects, while partial disturbance and complete clearance produce different recovery prospects.
For readers following climate and space science, the development is a useful example of how satellite observations can improve environmental reporting without turning a new dataset into a promise of certainty. ESA’s account connects a large body of research with the practical question facing national inventories: whether the numbers used to describe tropical forest carbon reflect both the damage that is visible and the degradation that is easier to miss.
