Brazil has long been a source of hope in the fight against climate change. Since 2004, the country has reduced annual deforestation in the Amazon by roughly 79%.

But now, as nations gather in Paris to negotiate a new global climate treaty, there are signs that this progress may have stalled — another reminder of just how hard it will be to decrease humanity’s impact on the planet. On 27 November, the Brazilian government announced that landowners had cleared 5,831 square kilometres of forest in 2015, an increase of 16% over last year.

Nature special: 2015 Paris climate talks

“We have probably a new dynamic on deforestation,” says Brazilian environment minister Izabella Teixeira, “and we need to know what is happening.”

Countries are pouring billions of dollars into the effort to protect the world’s forests, with Norway, Germany and the United Kingdom agreeing this week in Paris to provide US$5 billion until 2020. That figure includes substantial new aid to Brazil: $600 million from Norway until 2020, and $114 million from Germany.

Curbing deforestation could have substantial climate benefits. An analysis1 published last week estimates that aggressive forest management could offset roughly half of the globe’s current carbon emissions over the next decade. Reaching this target would require governments to halt tropical deforestation, which now produces as much as 10% of annual global carbon emissions. Nations would also have to stop development in cleared forest areas that are regrowing, and plant forests on land that is not being used for agriculture or other purposes.

But increasingly, environmentalists and governments are looking beyond the United Nations for solutions to forest loss. The UN climate framework includes a mechanism that allows wealthy nations to invest in tropical countries that curb deforestation and increase forest cover. Yet without a formal, global carbon market that would allow countries to offset their greenhouse-gas emissions by paying for forest conservation, the existing scheme is funded largely by government donations.

Tree by tree

Although environmentalists are working to ensure that forests are included in whatever climate agreement comes out of Paris, they have focused on helping individual governments to tackle deforestation and on building partnerships with the agricultural industry, which drives deforestation through the production of major commodities such as palm oil, beef and soya beans.

“I don’t think we can expect Paris or the United Nations system to create the markets we are going to need to protect forests and slow down global warming,” says Steve Schwartzman, an anthropologist and senior director of tropical forest policy at the Environmental Defense Fund in Washington DC.

Schwartzman, who has worked in Brazil since the 1980s, is not surprised by the recent uptick in forest loss there. Although the country’s government has made major progress against deforestation, it has yet to identify a system for rewarding landowners and local governments that are able to keep their forests standing.

“Getting below 5,000–6,000 square kilometres per year is going to be extremely difficult in the absence of any substantive positive incentives,” he says.

Still, Teixeira says that she is convinced that forests can make a difference in the fight against climate change — and that Brazil will meet its commitments in Paris to protect forests and reduce emissions over the next 15 years.

“I am not afraid,” she says. “We will achieve our goals, no problems, even considering the deforestation increase that we had last year.”