Experts urge policy nexus to nature, climate crises

The planet's massive losses of species and rising temperatures are unprecedented problems driven by human activities that must be tackled together, two of the world's leading scientific intergovernmental organizations said in a report on Thursday about their first collaboration.

Most policies on biodiversity — the variety of life in all forms — and climate change were crafted independently of one another but shouldn't be, according to the report published by 50 of the world's top biodiversity and climate experts.

"They are reinforcing each other," German climatologist and marine biologist Hans-Otto Pörtner, co-chair of a 12-person committee in charge of the collaboration, told a virtual press conference. He also pointed to a link between pandemics and biodiversity losses: the emergence of zoonotic diseases from species that thrive when biodiversity declines.

The experts recommended protecting carbon-rich habitats for species but avoiding climate solutions that hurt species diversity. "Human society depends on the services that nature provides, but climate change causes losses," Pörtner said. "Climate change and biodiverity are two of the most pressing issues."

Their report stemmed from a four-day virtual workshop in December between the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services and the United Nations Intergovernmental Panel on Climate Change.

It was peer-reviewed, but not formally approved by governments, and is meant to help leaders prepare for two major U.N. summits on biodiversity and climate change.

'Nature cannot do everything'

The joint IPBES-IPCC workshop report and accompanying scientific outcome highlighted the need to reduce deforestation and forest degradation, which will in turn help to lower human-caused greenhouse gas emissions. They also emphasized the importance of restoring ecosystems that create jobs and income, especially for indigenous peoples and local communities.

"Limiting global warming to ensure a habitable climate and protecting biodiversity are mutually supporting goals, and their achievement is essential for sustainably and equitably providing benefits to people," the report said. "Several land- and ocean-based actions to protect, sustainably manage and restore ecosystems have co-benefits for climate mitigation, climate adaptation and biodiversity objectives."

Soil conservation and less usage of fertilizer could offer huge offsets in carbon emissions, the report found, while the elimination of local and national subsidies could lessen deforestation, excessive fertilization and overfishing.

In 2019, IPBES reported that human actions were threatening 1 million plant and animal species with extinction and causing Earth’s natural life support systems to reach a breaking point. Its conclusions drew on the work of 145 wildlife experts from 50 countries over three years, with inputs from another 310 contributing authors.

The 50 experts with IPBES and IPCC called for protecting 30-50% of all ocean and land surface areas, up from 7.5% of oceans and 15% of all land now. They also urged reductions in waste and broader adoption of plant-based diets, especially in rich countries.

"Measures narrowly focused on climate mitigation and adaptation can have direct and indirect negative impacts on nature and nature’s contributions to people," the report found. "Measures narrowly focusing on protection and restoration of biodiversity have generally important knock-on benefits for climate change mitigation, but those benefits may be suboptimal compared to measures that account for both biodiversity and climate."

Oceans and land areas already absorb almost half of all human-caused carbon emissions, according to the report, but people must do much more by treating climate, biodiversity and human societies as "coupled systems" for our policies to succeed.

"Nature cannot do everything," IPBES chair Ana María Hernández Salgar, a Colombian researcher and international affairs expert, summed up.

"Transformative change in all parts of society and our economy is needed to stabilize our climate, stop biodiversity loss and chart a path to the sustainable future we want," she said. "This will also require us to address both crises together, in complementary ways."