Forests absorb carbon dioxide, support biodiversity, and deliver clear social and ecological benefits. Forest carbon offsets are cheaper and more publicly appealing than more complex technologies like carbon capture or direct air capture.
Yet new research led by the University of British Columbia [49.26°N, 123.25°W] warns that an overreliance on forest offsets could prove costly in both economic and climate terms.
The hidden risk of mitigation deterrence
The study shows that forest carbon offsets, while helpful, often act as a substitute for direct action. This phenomenon — mitigation deterrence — means that investments in renewables and carbon capture technologies decline when offsets are available. The modelling suggests renewable energy investment falls by nearly 9%, while carbon capture and storage drops by more than 30%. Meanwhile, fossil fuel investment ticks upwards.
This shift matters. If offsets are overvalued, or if forests later release carbon through wildfire, pests, drought, or logging, societies could be left with higher costs and fewer tools. The paper warns that if 100% of forest carbon gains are lost by 2045, the resulting economic hit could exceed the costs of never using offsets at all.
Impermanence and overestimation
Forests are not permanent vaults. California’s forest carbon programme, designed with a century-long buffer against fire, has seen that buffer nearly depleted in just a decade. Overestimation is another problem: studies suggest that avoided deforestation credits may be inflated by as much as threefold. This creates a dangerous illusion of progress, encouraging policymakers and businesses to claim climate success while actual emissions continue.
Unequal burdens
The risks are not distributed evenly. The study finds that non-OECD countries, where most new forestry projects are located, could face mitigation costs up to 1.7 percentage points higher than OECD nations in the event of offset failure. This compounds broader inequities: countries that are least responsible for historic emissions may be left carrying higher economic risks if offset schemes underperform.
Lessons for climate strategy
The message is not that forests have no role. Well-designed projects can store carbon, protect biodiversity, and strengthen local livelihoods. But the study underscores that forests cannot be treated as a universal substitute for reducing fossil fuel use. Instead, they should be deployed as a last resort — for the genuinely “hard-to-abate” emissions — rather than a cheap alternative to systemic decarbonisation.
Policy must therefore:
- Set clear rules on which emissions can be offset, and which must be cut directly.
- Avoid over-crediting by improving monitoring and verification of forest projects.
- Build resilience by combining natural solutions with technological ones, reducing the risk of dependence on any single approach.
- Consider equity, ensuring that offset markets do not transfer disproportionate risk onto countries with the least resilience.
A more sober perspective
The appeal of trees is understandable: they are visible, intuitive, and comforting in a crisis that often feels abstract. But the findings here remind us that nature-based solutions must be managed with humility. Forests can help us, but they cannot replace the hard work of phasing out fossil fuels, investing in renewables, and transforming economies.
If the transition to net zero is to be credible, carbon offsets must complement—not deter—direct mitigation. Otherwise, the world risks swapping the certainty of action today for the fragility of promises tomorrow.
Source
Mitigation deterrence and unrealistic expectations: the future costs of forest carbon offsets, Global Environmental Change, 2025-09-15
Boˆreal 