Decarbonisation & Nature-based Solutions
There are broadly two ways to respond to the climate crisis. The first is to stop making it worse by reducing the greenhouse gas emissions that are driving warming. The second is to work with natural systems that already draw down and store carbon, protecting and restoring them so they can continue to do so.
These are sometimes presented as alternatives, competing for attention, funding, and political will. In reality, the scale of the challenge is large enough that both are essential.
Decarbonisation
Decarbonisation means reducing the greenhouse gas emissions produced by human activity. It spans energy generation, industry, transport, agriculture, and buildings: everywhere that fossil fuels are burned or carbon-intensive processes occur.
The core logic is simple, even if the implementation is not. We know what is causing warming. Decarbonisation is the work of stopping it. Without significant progress here, no other approach can compensate for continued emissions at scale.
Nature-based solutions
Nature-based solutions (nature-based solutions) work with ecosystems that already draw down atmospheric carbon and store it over time. The focus is on protection, conservation, and restoration: keeping intact what works, recovering what has been lost, and managing landscapes and seascapes to maximise their carbon value alongside their ecological value.
On land (e.g. forests, soils, wetlands)
Old-growth forests store vast amounts of carbon accumulated over centuries. Peatlands and wetlands are among the most carbon-dense ecosystems on Earth. Restoring degraded soils can increase both carbon storage and agricultural resilience.
In the ocean (e.g. seagrass, mangroves, saltmarsh, sediment)
Coastal ecosystems, sometimes called blue carbon habitats, sequester carbon at rates far exceeding most terrestrial forests. Much of that carbon ends up not in the plants themselves but in the sediment beneath them, where it can remain stable for millennia, extending the same picture to the seabed carbon stores of the wider continental shelf.
Cristina Mittermeier / Sea Legacy
Not geoengineering
Nature-based solutions are sometimes confused with geoengineering. These are large-scale technological interventions designed to alter Earth's systems, such as spraying reflective particles into the stratosphere to reduce solar radiation. In contrast, nature-based solutions works with processes that already exist in nature.
Current policy debates
Nature-based solutions have gained significant momentum in climate policy, and with that momentum has come scrutiny. Several genuine tensions are worth understanding:
- Permanence: a forest planted today can burn, be logged, or die under drought. Carbon stored in living ecosystems is not as stable as carbon kept in the ground. How do you account for this in policy?
- Land use competition: restoring forests or wetlands at scale requires land, which may also be needed for food production, housing, or existing communities. These trade-offs are real and unresolved.
- Additionality: would the ecosystem have been protected anyway? Carbon credits for nature-based solutions have faced criticism for counting conservation that would have happened regardless.
- Scale: even optimistic estimates suggest nature-based solutions can provide perhaps 20–30% of the mitigation needed by 2030. It is significant, but it cannot substitute for emissions reductions.
Why we need both
Decarbonisation and nature-based solutions are not competing for the same job. Decarbonisation cuts the emissions at source. Nature-based solutions help draw down and store what's already in the system. The IUCN estimates that nature-based solutions could deliver around 30% of the mitigation needed by 2030 and 2050. That leaves roughly 70% that has to come from decarbonising our economies. Neither figure works without the other.
Oxford's Nature-based Solutions Initiative put this sharply. As Myles Allen has said, corporate claims of ambitious climate goals don't stack up if medium-term plans treat nature as a substitute for cutting fossil fuel emissions, rather than a complement to it.
Ocean Image Bank / Fabrice Dudenhofer
So nature-based solutions are not a get-out-of-jail-free card. They are also not the junior partner in the relationship. Properly protected and restored ecosystems deliver food security, clean water, flood protection, and human health alongside their carbon value. There's something harder to quantify, too: the joy of encountering a thriving, living world. That's worth protecting in its own right, carbon aside.