Mass extinction and the climate emergency each pose an existential threat to life as we know it. A new landmark report shows they must be tackled in tandem to give nature — and by extension, us — the best shot at survival.
The report, released on Thursday morning, was compiled by 50 top climate and extinction experts for the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services and the Intergovernmental Panel on Climate Change on Thursday morning. It’s the first-ever joint collaboration between these two bodies, both of which have released seminal reports in recent years on the climate crisis and the collapse of nature. Their collaboration shows the urgency of these issues as truly catastrophic impacts loom.
So far, the authors say, most international policy has treated biodiversity loss and global warming like they are independent issues, and world leaders have formed separate conventions and intergovernmental bodies to take on each one. But leaders must more carefully consider how the issues intersect if they actually want to solve the crises.
It’s not as though scientists haven’t called out the interrelatedness of these two crises before. Though few extinctions have been conclusively linked to climate change so far, major biodiversity reports have noted that the climate crisis is a growing threat.
“[W]e are finding that while organisms have remarkable capacities to cope with changing, warming environments … they can’t keep pace with climate change, either by moving in space or time or by physiologically coping in place,” Sarah Diamond, associate professor of biology at Case Western Reserve University in Cleveland and a report author, wrote in an email.
It’s clear that warming waters and atmospheric temperature are becoming less hospitable to many marine and terrestrial creatures alike. Ocean acidification, another impact of rising carbon pollution, poses an equally dire threat to marine habitat. More chaotic weather, searing droughts, and rising seas are also adding pressure.
As biodiversity diminishes, that can, in turn, push crucial ecosystems to the point of collapse. That includes, as climate scientists have long warned, greenhouse gas-sequestering ecosystems like coral reefs, mangroves, and rainforests, as well as carbon-regulating freshwater lakes, wetlands, and rivers.
“Climate change would be much worse right now without that natural sink function that nature provides us; it’s a free subsidy that we really haven’t sufficiently appreciated,” Pam McElwee, associate professor of human ecology at Rutgers and one of the report authors, wrote in an email.
But understanding and appreciating the link between the extinction and climate crises, the new report says, isn’t enough. Policymakers must come up with solutions that consider the effects of both. Otherwise, strategies to tackle each one could end up exacerbating the other.
“Generally most things that we might do for biodiversity, such as expand protected areas or institute species protections, are either beneficial for climate or at least neutral,” said McElwee. “But the reverse is not true; some climate policies are likely to potentially harm biodiversity or at least instigate some serious trade-offs.”
For instance, planting crops that suck up carbon and help the soil do the same can help lower greenhouse gas emissions. But prioritising that as a climate mitigation strategy could also wipe out habitat for wildlife as well as disrupt Indigeous practices. If the crops’ growth is aided by pesticides and fertilisers, the effect can be even worse. Similarly, building renewable energy requires elements often found in delicate regions of the world. If we’re not careful, mining for those materials could harm ecosystems and cause some species to go extinct.
The scientists make specific recommendations for policies that better tackle both issues, including halting the loss of carbon-sequestering and biodiverse ecosystems. Many of the world’s crucial greenhouse gas sinks — like the Amazon and Congo rainforests, coastal mangrove forests, and the Pantanal wetland in South America — are also some of the world’s most biodiverse regions.
The authors also suggest adopting more sustainable agricultural and forestry practices. Diversifying crops and phasing out the use of harsh pesticides and fertilisers can both protect species and allow soils and plants to suck up more carbon dioxide. The report also notes that reducing deforestation and forest degradation can not only protect rich ecosystems, but result in 5.8 gigatonnes of carbon dioxide equivalent pulled from the atmosphere every year. That’s about 15% of all human emissions annually.
But beyond taking up these specific suggestions, the authors say that a truly comprehensive response to both the climate and biodiversity crises will require world leaders to shift their understanding of how human society should relate to the rest of the world.
“Solving some of the strong and apparently unavoidable trade-offs between climate and biodiversity will entail a profound collective shift of individual and shared values concerning nature,” Hans-Otto Pörtner, a climate scientist who co-chaired the report working group’s scientific steering committee, said in a statement.
That includes deprioritizing GDP growth above all else, and instead factoring the natural world into all economic decisions. It also includes recognising the rights and sovereignty of Indigenous populations, which studies show are the communities best-suited to protect biodiversity and the climate.
This may all sound quite radical. Right now, the world is locked in a chase for growth and profit above all else. Exploiting human and nonhuman life in that pursuit is seen as Just the Way Things Work. But the reality is this system isn’t working for the natural world (to say nothing of billions of people around the globe), and it could give out completely if we don’t change course.
“Tackling climate and biodiversity together … is going to be a task unlike any we have attempted before,” McElwee, said. “It’s really all hands on deck.”