The Amazon Rainforest Has Already Reached a Crucial Tipping Point

ENVIRONMENT, 12 Sep 2022

Luke Taylor | New Scientist – TRANSCEND Media Service

About 26 per cent of the Amazon rainforest has already been lost or badly degraded and without intervention the rest could transform into savannah, says a report on its status.

Trees in many parts of the Brazilian Amazon are being cut down and burned to make space for agriculture.  Kristof Bellens/EyeEm/Alamy

5 Sep 2022 – Indigenous leaders from the nine countries and territories that encompass the Amazon region have presented a report today that says so much of the rainforest has been lost that it has reached a crucial tipping point, that would turn forest to savannah, earlier than expected.

Vast swathes of the southern Amazon rainforest have gone and the rest will follow if deforestation isn’t halted, the leaders told the fifth Summit of Indigenous Peoples in Lima, Peru.

Researchers have predicted that once a certain amount of the Amazon rainforest is lost, it will no longer be able to hold the necessary moisture and generate the rainfall it needs to support itself. This would set off a chain reaction as the world’s largest rainforest transforms into a savannah incapable of regenerating itself.

When this tipping point will occur is unclear, but 2019 work found that 17 per cent of the Amazon basin’s rainforest had been lost, and an estimate from 2018 put the future threshold at about 20 to 25 per cent of combined loss and degradation.

Surging deforestation in recent years means that threshold has already been passed, finds the latest report. It says that about 20 per cent of the Amazon has been cleared and another 6 per cent highly degraded in about 35 years.

Marlene Quintanilla at the Amazon Geo-Referenced Socio-Environmental Information Network (RAISG) and her colleagues, working in partnership with various groups, including the Coordinator of Indigenous Organizations of the Amazon River Basin, used forest coverage data to map how much of the Amazon was lost between 1985 and 2020 and also looked at forest density, rainfall patterns and carbon storage.

The rainforest’s abilities to store carbon and regulate precipitation are indicators of its capacity to survive, says Quintanilla, and studying them can also reveal the effects of forest fires beneath the canopy, which satellite images can miss.

The report finds that 33 per cent of the Amazon remains pristine and 41 per cent of areas have low degradation and could restore themselves. But 26 per cent of areas have been found to have gone too far to restore themselves: 20 per cent is lost entirely and 6 per cent is highly degraded and would need human support to be restored.

“The ecological response of the forest is changing and its resilience is being lost,” says Quintanilla. “We are at a point of no return.”

The Amazon may span 847 million hectares, but distant regions are highly interdependent. Losing trees in one area of the rainforest means there is less rainfall, higher temperatures and less CO2 absorption in others, which makes them more susceptible to fires and less resilient to climate change, feeding back into the cycle of destruction.

The transformation is already visible in Brazil and Bolivia, say the report’s authors. These two nations account for 90 per cent of all combined deforestation and degradation in the Amazon.

In the past 20 years, rainfall in parts of the Bolivian Amazon has reduced by 17 per cent and the temperature has risen by 1.1°C. Areas of dense rainforest are becoming savannah and trees in the north of the country have stopped producing the fruits that uncontacted Indigenous groups depend on to eat, says Quintanilla.

If agriculture, mining and other drivers of deforestation don’t cease, that process will spread quickly to other countries, say the authors.

About 86 per cent of deforestation has occurred in areas outside national or Indigenous reserves, and given that 48 per cent of the Amazon remains unprotected by reserves, those areas will be lost unless they are given protection, say the researchers.

Indigenous reserves were found to be slightly better conserved than national parks, despite having less government investment and support. So the authors suggest that the best way to save the rainforest is by designating unprotected land as Indigenous territory.

Efforts should also be made to restore the 6 per cent of rainforest (54 million hectares) with high degradation, say the authors, to prevent the Amazon becoming savannah.

Carlos Nobre at the University of Sao Paulo in Brazil has been running climate models for three decades to understand when the Amazon could reach its tipping point and how it could look.

“Unfortunately what we’re seeing today is no longer based on models. What we are seeing today is observations across the entire southern Amazon that indicate that the risk of this tipping point is immediate,” he says. “The RAISG study showing the high levels of deforestation and degradation is very, very, very worrying.”

The length of the dry season in the southern Amazon, which makes up a third of the entire rainforest, now lasts four to five months, five weeks longer today than it was in 1999, says Nobre. If it reaches five to six months, it will no longer survive.

____________________________________________

Luke Taylor is a freelance journalist covering Latin America, usually from Bogotá, Colombia. He reports for leading medical and science publications, including The BMJ, New Scientist, Nature and Scientific American. Luke’s science reporting focuses on life sciences, health and the environment — particularly the Amazon rainforest.  He also writes news and features on conflict, migration and the international drug trade for publications such as ABC News and The Telegraph.

Go to Original – newscientist.com


Tags: , , , , , , , , , , , , , , , , , , , , , , ,

 

Share this article:


DISCLAIMER: The statements, views and opinions expressed in pieces republished here are solely those of the authors and do not necessarily represent those of TMS. In accordance with title 17 U.S.C. section 107, this material is distributed without profit to those who have expressed a prior interest in receiving the included information for research and educational purposes. TMS has no affiliation whatsoever with the originator of this article nor is TMS endorsed or sponsored by the originator. “GO TO ORIGINAL” links are provided as a convenience to our readers and allow for verification of authenticity. However, as originating pages are often updated by their originating host sites, the versions posted may not match the versions our readers view when clicking the “GO TO ORIGINAL” links. This site contains copyrighted material the use of which has not always been specifically authorized by the copyright owner. We are making such material available in our efforts to advance understanding of environmental, political, human rights, economic, democracy, scientific, and social justice issues, etc. We believe this constitutes a ‘fair use’ of any such copyrighted material as provided for in section 107 of the US Copyright Law. In accordance with Title 17 U.S.C. Section 107, the material on this site is distributed without profit to those who have expressed a prior interest in receiving the included information for research and educational purposes. For more information go to: http://www.law.cornell.edu/uscode/17/107.shtml. If you wish to use copyrighted material from this site for purposes of your own that go beyond ‘fair use’, you must obtain permission from the copyright owner.


There are no comments so far.

Join the discussion!

We welcome debate and dissent, but personal — ad hominem — attacks (on authors, other users or any individual), abuse and defamatory language will not be tolerated. Nor will we tolerate attempts to deliberately disrupt discussions. We aim to maintain an inviting space to focus on intelligent interactions and debates.

*

code

Note: we try to save your comment also when there are technical problems or a mistake in the Captcha. Still, for long comments we recommend that you copy them somewhere else as a backup before you submit them.

This site uses Akismet to reduce spam. Learn how your comment data is processed.