The Amazon rainforest provides up to 20% of the world's oxygen, but its destruction could cause it to not only stop helping the planet, but start releasing carbon and worsening climate change.

In a "dieback" scenario, rising temperatures could dry trees, meaning they absorb less carbon and become more flammable, eventually turning the rainforest into a savannah and releasing billions of tons of stored carbon.

Researchers have debated the likelihood of the scenario, but fears have heightened under Brazil's new president, who has advocated expansion of industry in the region, which involves burning and cutting down trees.

A record number of fires have hit the Amazon this year — more than 70,000 — and experts say they are due to human activity.

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The record number of fires raging across the Amazon rainforest in 2019 could be part of a doomsday "dieback" scenario in which the rainforest spews carbon into the atmosphere and speeds up climate change even more.

More than 70,000 fires have been recorded this year in the rainforest, which produces between 6% and 20% of the world's oxygen — threatening its future, the billions of plants and animals that call it home, and possibly the entire planet's health.

If more of the Amazon is destroyed, not only would it stop producing this oxygen and supporting wildlife, but it could create a feedback loop that worsens climate change.

Read more: Here's what you can do to help the burning, ravaged Amazon rainforest

A dieback process, in which climate change speeds up the loss of trees and changes the landscape, could start with just some of the Amazon's destruction, Business Insider's Aylin Woodward reported.

Losing 20% of Brazil's rainforest could result in such a feedback loop, which would dry trees, leaving them unable to absorb as much carbon and much more flammable and likely to spread fires, researchers from three British universities wrote in a post for The Conversation.

A tract of Amazon jungle burning as it's cleared by loggers and farmers in Novo Airao, Brazil. Reuters

This tipping point could lead the Amazon to devolve into a barren, savannah-like landscape that not only fails to produce oxygen but could cause the release of the 140 billion tons of carbon stored in the rainforest into the atmosphere, the Rainforest Trust said in a 2017 post.

Rising global temperatures also threaten the future of remaining trees in aiding the planet. A 2000 study found that rising temperatures could stop trees in the Amazon from absorbing oxygen by as early as 2050 and that they could start to emit carbon instead.

Members of Suriname's indigenous tribes pray for the protection of the Amazon and Brazilian indigenous tribes on August 9. REUTERS/Ranu Abhelakh

Some studies have described this scenario as "improbable," but fears for the rainforest's future have been heightened as human destruction of the Amazon speeds up.

Brazilian President Jair Bolsonaro has advocated industrial development in the Amazon and has tried, without evidence, to blame nongovernmental organizations for the fires.

Read more: The Amazon is burning at a rate not seen since we started keeping track. The smoke is reaching cities 2,000 miles away.

According to The Guardian, July saw significantly increased deforestation in the Amazon as farmers and logging companies heightened their presence in the region.

Satellite data from July showed that a soccer-pitch-sized area of the rainforest was being cleared every minute, the BBC said.

A deforested area near Novo Progresso, in Brazil's northern state of Para, in 2009. AP Photo/Andre Penner

Wildfires have always occurred in the Amazon, but they are sped up by hot, dry conditions. And some of the fires are started by those engaging in farming and logging.

Earlier this week, the Brazilian city of Sao Paulo, 2,000 miles from the rainforest, was plunged into darkness as smoke from the fires obscured the sun.

Read more: Brazil's president baselessly claimed that NGOs set the Amazon on fire on purpose to make him look bad

Ricardo Mello, the head of the World Wide Fund for Nature's Amazon Program, said that the fires were "a consequence of the increase in deforestation seen in recent figures," the BBC reported.

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