Rewild the World
By George Monbiot
We launch a new campaign to allow ecosystems to recover on a
massive scale, drawing down carbon from the atmosphere
I don’t expect much joy in writing about climate breakdown.
On one side, there is grief and fear; on the other side, machines. I became an
environmentalist because I love the living world, but I spend much of my life
thinking about electricity, industrial processes and civil engineering.
Technological change is essential, but to a natural historian it often feels
cold and distancing. Today, however, I can write about something that thrills
me: the most exciting field of research I have covered in years.
Most climate scientists agree that it is now too late to
prevent 1.5°C or more of global heating only by cutting our production of
greenhouse gases. Even if we reduced our emissions to zero tomorrow, we would
probably overshoot this crucial temperature limit. To prevent a full-spectrum
catastrophe, we need not only decarbonise our economy in the shortest possible
time, but also to draw down carbon dioxide that has already been released.
But how? The best-known proposal is called bio-energy with
carbon capture and storage (BECCS). This means growing wood or straw in
plantations, burning it in power stations to produce electricity, capturing the
carbon dioxide from the exhaust gases, and burying it in geological formations.
If deployed at scale, it is likely to trigger either an ecological or a
humanitarian disaster.
One BECCS proposal, favoured by certain governments, would
cover an area three times the size of India with plantations. This involves
either converting agricultural land, in which case BECCS would cause mass
starvation, or converting wild land, in which case almost-lifeless plantations
would replace 50% of the world’s remaining natural forests. Even so, it might
not be effective, as any carbon savings will be counteracted by the use of
nitrogen fertiliser and the release of greenhouse gases from the soil as it’s
churned up for planting. BECCS can lead only to catastrophe, and should be
immediately abandoned.
Another option is direct air capture: extracting carbon
dioxide with machines. Aside from the expense, which is likely to be massive,
the amount of steel and concrete required to build them could help to push the
world beyond certain climate tipping points before the positive effects are
felt.
None of this is necessary, because there’s a much better and
cheaper way of doing it. Natural climate solutions draw carbon from the air
through the restoration of living systems. They could help to solve two
existential problems at once: climate breakdown and ecological breakdown. Their
likely contribution is enormous – bigger than almost anyone guessed a few years
ago – and it is still scarcely explored.
The greatest potential identified so far – as so much land
can be used this way – is in protecting and restoring natural forests and
allowing native trees to repopulate deforested land. The greatest drawdown
potential per hectare (though the total area is smaller) is the restoration of
coastal habitats such as mangroves, saltmarsh and seagrass beds. They stash
carbon 40 times faster than tropical forests can. Peaty soils are also vital
carbon stores. They’re currently being oxidised by deforestation, drainage,
drying, burning, farming and mining for gardening and fuel. Restoring peat, by
blocking drainage channels and allowing natural vegetation to recover, can suck
back much of what has been lost.
These are the best-studied natural climate solutions. Others
have scarcely been explored. For example, we currently have little idea of what
the impact of industrial fishing might be on the seabed’s vast carbon store. By
disturbing the sediments and lifting the carbon they contain into the water
column, trawlers and dredgers are likely to expose it to oxygen, turning it
into carbon dioxide. One study suggests that repeated trawling in the
north-western Mediterranean has caused a reduction in carbon storage in the top
10 centimetres of sediments of up to 52%. Given the vast area trawled every
year (most of the seabed on the world’s continental shelves), the climate
impact could be enormous. Closing large parts of the seas to trawling could
turn out to be a crucial climate strategy.
Scientists have only recently begun to explore how the
recovery of certain animal populations could radically change the carbon
balance. For example, forest elephants and rhinos in Africa and Asia and tapirs
in Brazil are natural foresters, maintaining and extending their habitats as
they swallow the seeds of trees and spread them, sometimes across many miles,
in their dung. White rhinos can play a major role in preventing runaway
wildfires in African savannahs. If wolves were allowed to reach their natural
populations in North America, one paper suggests, their suppression of
herbivore populations would store as much carbon every year as between 30 and
70 million cars produce. Healthy populations of predatory crabs and fish
protect the carbon in salt marshes, as they prevent herbivorous crabs and
snails from wiping out the plants that hold the marshes together.
What I love about natural climate solutions is that we
should be doing all these things anyway. Instead of making painful choices and
deploying miserable means to a desirable end, we can defend ourselves from
disaster by enhancing our world of wonders. However, nothing should be done
without the involvement and consent of indigenous people and other local
communities. Nor should damaging projects, such as monocultural plantations, be
passed off as natural climate solutions. As a paper published this week in
Nature shows, several governments are attempting this deception.
Today, a small group of us launch a campaign for natural
climate solutions to receive the commitment and funding they deserve. At the
moment, though their potential is huge, they have been marginalised in favour
of projects that might be worse than useless, but that are profitable for
corporations. Governments discuss the climate crisis and the ecological crisis
in separate meetings, when both disasters could be addressed together. We have
created a dedicated website, an animation, and a letter signed by prominent
activists, scientists and artists.
We don’t want natural climate solutions to be used as a
substitute for the rapid and comprehensive decarbonisation of our economies.
The science tells us that both are needed: the age of carbon offsets is over.
But what this thrilling field of study shows is that protecting and rewilding
the world’s living systems is not just an aesthetically pleasing thing to do.
It is an essential survival strategy.
monbiot.com
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