Think Summer is Hot Now? Here’s how hot it would be without nature.

September 16, 2021

Arlington, VA (September 16, 2021) – Without the complex web of species and ecosystems on land and under water – collectively known as Earth’s biosphere – global average temperature today would have already surpassed the critical 1.5º C threshold, a benchmark signifying that the planet’s warming is moving into the zone of dangerous climate change. According to research from scientists working with Conservation International published today in Proceedings of the National Academy of Sciences (PNAS), it is Earth’s biosphere to thank for not yet reaching this critical threshold.

The paper, co-authored by Conservation International scientists Johan Rockström, chief scientist at Conservation International and director of the Potsdam Institute for Climate Impact Research; Conservation International scientists Dave Hole, Bronson Griscom, Mike Mascia; and partners, details the often downplayed or hidden ‘climate stabilization’ role played by the biosphere.

Currently, oceans, forests and other ecosystems absorb and store half of humanity’s annual carbon footprint in what the authors call “a vast subsidy to the world economy.” To effectively avert further, and far more dangerous impacts from climate change, focus must be on both preserving and enhancing nature’s climate stabilization role right alongside efforts to transition away from fossil fuels.

Yet the biosphere has already been profoundly altered by humanity, which has destroyed half of the world’s plant biomass. If current trends continue, some regions in the tropics could become a net source of carbon, rather than a sink.

Globally, less than 25% of all land area remains mostly unaffected by human impacts, with just 5% of the oceans untouched. Ultimately, this puts nature’s own ability to mitigate climate change significantly at risk.

“Troublingly, the biosphere’s natural balance is slowly succumbing to human pressures and climate change impacts,” said Rockström. “Humanity needs to act now – as stewards of nature – to restore and protect the vast ecosystems that halve our carbon emissions each year. Otherwise, we will not meet the critical benchmarks for the coming decade, as outlined in the Paris Agreement.”

In the short term, this stewardship must include three core elements, according to the researchers:

  1. Halving emissions each decade to achieve carbon neutrality by 2050,
  2. Shifting forestry and farming methods away from a reliance on habitat degradation and destruction and
  3. Restoring and expanding natural carbon-absorbing ecosystems  

“We already have the tools we need to help prevent a climate crisis – and nature provides many of them,” said Dave Hole, a co-author of the paper and vice president of Global Solutions at Conservation International’s Moore Center for Science. “Our findings highlight the importance of ‘natural climate solutions’ – actions to conserve, sustainably manage and restore the biosphere. These actions not only provide about a third of the additional climate mitigation needed to keep global temperature rise well below 20C, they also improve resilience of existing natural carbon sinks to future warming. But we need to act now and act globally – across our social, economic and political systems – to fully leverage nature’s role in preventing dangerous climate change”

The researchers found that large scale stewardship of the biosphere could reduce warming by 0.3 º C by the end of this century – a vital contribution to “remaining well below 20C,” the goal of the Paris Climate Agreement. This finding aligns with and builds upon the results of the 2017 landmark study, led by co-author Bronson Griscom, that revealed the critical climate mitigation role of natural climate solutions, including avoiding emissions, sustainable management of working lands and restoration.

To achieve such stewardship over the next decade, Conservation International scientists urge collaboration between the public and private sectors, collectively establishing emissions targets and working with Indigenous peoples locally to protect nature – including locations with irrecoverable carbon, the places that if destroyed or degraded would release so much carbon that they must be protected to avoid catastrophic climate change.

To avoid potentially irreversible biosphere damage and worsening climate change, these efforts must begin urgently, globally and in parallel, scaling exponentially over the coming decade. This study sounds a clarion call on the level of ambition needed and the urgency of action – there is just a small window of time remaining to take decisive action on biosphere stewardship.

Recognizing that urgency, Conservation International scientists will release a first-of-its-kind “roadmap” for maximizing nature’s full potential to fight climate change early in 2022. 


About Conservation International Conservation International works to protect the critical benefits that nature provides to people. Through science, partnerships and fieldwork, Conservation International is driving innovation and investments in nature-based solutions to the climate crisis, supporting protections for critical habitats, and fostering economic development that is grounded in the conservation of nature. Conservation International works in 30 countries around the world, empowering societies at all levels to create a cleaner, healthier and more sustainable planet. Follow Conservation International's work on Conservation NewsFacebookTwitterInstagram and YouTube.