At a time when the world is grappling with meeting the Paris Climate Agreement and trying to prevent the sixth mass extinction on Earth, an international team of scientists has published a way forward - a Global Deal for Nature.

The science-backed plan, published in Science Advances, proposes ambitious targets for the conservation of nature as the most effective pathway to address the extinction crisis and help us avert catastrophic climate change, before it’s too late.

The deal calls for 30% of the planet to be protected by 2030, with an additional 20% to be maintained or restored to a natural state and designated as climate stabilization areas.

Biodiversity – the variety of life on Earth, from species to ecosystems – has a close relationship to climate change. Tropical forests, for example, are home to more than half of all species on land, and capture more of our carbon pollution than any other terrestrial ecosystem. They also sequester much more carbon than planted monocultures.

The same is true for other ecosystems, such as intact mangroves and seagrass beds, which are sites of great biodiversity that store more carbon than coastal areas that have been degraded.

But we have already transformed over half of Earth’s land to produce our food, and severely damaged our oceans. As a result, not only are we losing species at a rate 1000 times greater than the natural extinction rate, but we are also losing the ability of the natural world to rid us from our own pollution.

At the moment, 45% of the planet is still in a natural or semi-natural state. But this is changing rapidly, putting severe pressure on the survival of many species, and contributing to an acceleration of climate change. In recent years, 15% of annual greenhouse gas emissions came from forest clearing and fires in Indonesia and Brazil alone.

The science shows that we are approaching tipping points on all fronts. If current trends in greenhouse gas emissions, the conversion of natural habitats and the poaching of large animals are not reversed, it will be impossible to keep warming below 1.5°C. Many ecosystems and species will simply unravel and disappear.

The case for conservation

We know that well-managed protected areas are effective in safeguarding biodiversity and increasing the resilience of ecosystems, both on land and in the ocean. In marine reserves where commercial fishing is prohibited, the biomass of fish is six times greater than in adjacent unprotected areas. Nearby areas also benefit from the spillover of fish, which helps to replenish local fisheries.

Governments agreed to protect 17% of land and 10% of the ocean by 2020. But today, we are falling short, with 15% of land protected and 7% of the ocean.

More importantly, the scientific literature overwhelmingly indicates that these existing targets are insufficient to avoid extinctions, halt the loss of biodiversity or maintain key ecosystem services.

A new deal

The Global Deal for Nature analyzed how much of the planet we need to maintain to ensure that our ecosystems continue to harbour an abundance of species, and provide services essential for human life, including carbon sequestration.

The study used existing classifications of eco-regions as a framework to assess the percentage of land, freshwater and ocean resources that need to be covered by protection measures. The analysis also looked at key biodiversity areas, biodiversity hotspots and old-growth carbon reservoirs, as well as the connectivity between protected areas, which is important for species that migrate or require large habitats.

The Global Deal for Nature concludes that we need to protect at least 30% of the Earth’s surface by 2030, and provides a framework for the distribution of this 30% across the most important areas for biodiversity.

But that’s not enough. Given that terrestrial carbon sinks currently absorb a quarter of emissions, the scientists conclude that if we want to remain below a 1.5°C warming scenario, we need to designate an additional 20% of the planet as climate stabilization areas.

Climate stabilization areas would cover natural reserves of carbon, such as mangroves, tundra, boreal and tropical forests. In these areas, land conversion needs to be restricted. For example, in critical places such as the Amazon, we have to maintain at least 85% of the forest cover to avoid a shift to a savannah. The Amazon generates its own rain and weather patterns. But if more than 15% of the current forest is cleared, it will lose its ability to self-generate enough rain to keep itself as it is, with consequences for global weather patterns.

To achieve 30% protected areas plus 20% climate stabilization areas, the Global Deal for Nature highlights the essential role of indigenous peoples as traditional stewards of their lands and livelihoods.

What about other threats?

As a complement to the protection targets, the Global Deal for Nature offers policy recommendations for reducing the threats that exert pressure on the natural world, such as:

- Slowing and stopping the clearing of intact natural habitats for agriculture, directing cropland to lands that have already been degraded, and focusing on reducing food waste

- Putting in place proactive approaches to govern roads, dams and energy development projects

- Managing fisheries according to scientific targets

- Reducing plastic and chemical pollution, which harms the air, water, land and species on which we depend

How much will this cost?

The Global Deal for Nature estimates that the cost of nature conservation measures across half the Earth could be $100 billion per year. Current spending on conservation is less than 10% of that. Additional sources of funding will be needed, including private sector investment. Yet conservation will open up new opportunities and direct financial benefits. Estimates suggest that increased annual profits could range from $53 billion in the seafood industry to $4.3 trillion in the insurance industry.

Time to act

The good news is that combining the Paris Climate Agreement with the Global Deal for Nature provides a clear pathway for action. If we ensure that at least half the planet is in an intact natural state by 2030, and combine this with energy transition measures, we can still halt the current trend in species loss, and keep the rise in global average temperatures below 1.5°C.

The message is clear and so is the pathway. But time is running out. We need to take a bold stand and act upon it now. Will you join us?