The Amazon rainforest is ‘fuelling’ global warming, with huge areas producing more carbon than they absorb due to deforestation, according to a new study.
A combination of fires and logging in the rainforest has seen large regions switch from being an essential ‘carbon sink’ to being a carbon emitter, National Institute for Space Research in Sao Jose dos Campos, Brazil researchers discovered.
This shift is is further fuelling the global warming crisis, which is leading to increasing ‘extreme weather events’ and the team say ‘each year it’s getting worse’.
Through the extensive observations, they found southeastern Amazonia – about 20 per cent of the whole area – switched to being a substantial source of CO2.
Professor Simon Lewis, a climate change expert from UCL, not involved in the study, told MailOnline this is yet more evidence of an urgent need to reach net zero carbon emissions as quickly as possible to prevent further damage to the climate.
The Amazon rainforest is ‘fuelling’ global warming, with huge areas producing more carbon than they absorb due to deforestation, according to a new study
A combination of fires and logging in the rainforest has seen large regions switch from being an essential ‘carbon sink’ to being a carbon emitter, National Institute for Space Research in Sao Jose dos Campos, Brazil researchers discovered
Where is Earth’s Carbon stored?
Amazon rainforest: 200 billion tonnes
Siberian permafrost: 950 billion tonnes
Arctic: 1,600 billion tonnes
Oceans: As much as 38,000 gigatonnes, according to World Ocean Review
These figures are estimates, but true values may be higher. By contrast, humans produce an estimated 36 billion tonnes of carbon annually.
Lead author Professor Luciana Gatti, said deforestation and regional climate change is threatening the atmospheric carbon buffering potential of the rainforest.
Essentially, without the deforestation, the rainforest could soak up some of the carbon emitted by human activity, forestalling the worst impacts of climate change.
Millions of trees have been lost, meaning they can no longer take the CO2 from the air as they grow, and instead release the CO2 as they die due to fires and logging.
This is further hindering United Nations efforts to keep global average temperatures from rising by more than 3.6F over pre-industrial levels by 2100, a figure some studies suggest we may exceed in the next decade.
Amazonia represents the greatest expanse of tropical forest on the planet and the shimmering green leaves play a vital role in storing atmospheric carbon.
They convert the greenhouse gas through photosynthesis into carbohydrates that end up in the woody trunks and branches, acting as a ‘carbon sink’.
This shift is is further fuelling the global warming crisis, which is leading to increasing ‘extreme weather events,’ including forest fires, and the team say ‘each year it’s getting worse’
THE KEY GOALS OF THE PARIS CLIMATE AGREEMENT
The Paris Agreement on Climate Change has four main goals with regards to reducing emissions:
- A long-term goal of keeping the increase in global average temperature to well below 2°C above pre-industrial levels
- To aim to limit the increase to 1.5°C, since this would significantly reduce risks and the impacts of climate change
- Governments agreed on the need for global emissions to peak as soon as possible, recognising that this will take longer for developing countries
- To undertake rapid reductions thereafter in accordance with the best available science
Source: European Commission
However, the new study, published in Nature by Brazilian climate scientists, sheds fresh light on the influence of humans on the vital region.
‘Factors such as deforestation and climate change are thought to have stimulated a decrease in the capacity,’ said Professor Gatti.
‘They have altered the local balance of carbon gases – which is indicative of the health of an ecosystem.’
The discovery is based on 590 observations of carbon dioxide and monoxide concentrations over almost a decade within the Amazonia region.
Every two weeks from 2010 to 2018 the researchers flew over four sites of the Amazon basin in aircraft fitted with sensors.
They focused on the troposphere – the lowest layer of the atmosphere, which stretches up to three miles above sea level, to discover the shift.
The area most notably impacted is the southeastern area of Amazonia, which accounts for about 20 per cent of the entire rainforest.
‘Stress inflicted on local ecosystems and an increase in fire occurrence – promoted by an intensification of the dry season and deforestation – may be responsible for the higher emissions,’ said Professor Gatti.
‘Deforestation and climatic changes may have lasting, negative consequences for both the carbon balance of the region and the fragility of its ecosystems.’
Logging in Brazil hit a 12-year high in 2020 – increasing nearly 10 per cent from the year before, according to the study authors.
The Amazon slows the pace of global warming by storing up to 200 gigatons of carbon – equivalent to five years worth of human emissions.
The researchers – including staff at the universities of Exeter and Leeds – say it’s becoming a carbon source faster than feared.
At 2.72 million square miles, the rainforest is roughly the size of the United States – covering 40 per cent of the South American continent.
More than half of the Amazon rainforest could be transformed into savanna within the next 30 years, warned the study authors
They tracked forestation against rainfall and temperature – as well as the average emissions over the course of nine years by flying over four sites every two weeks with sensors
CARBON SINK SHIFT: WHY DOES IT MATTER?
Parts of the Amazon rainforest are shifting from being carbon sinks, to being carbon emitters.
But why is this a problem on a global scale? Professor Mark Maslin from UCL, and author of ‘How to Save Our Planet’ published by Penguin, explains:
‘About a quarter of all the carbon dioxide humans emit into the atmosphere is taken up by the biosphere – especially by our forests.
‘But deforestation due to logging, agriculture, wildfires and climate change is reducing both the amount of forests and their ability to soak up our pollution.
‘A recent study in Nature show that this switching from taking up carbon to releasing carbon has already started to happen in large parts of the southeast Amazonia.
‘If this continues it will make getting to global net carbon zero by 2050 much more difficult and hence why we must protect and if possible, expand the forests of the World.’
For decades, scientists have warned of an ‘Amazon tipping-point’, that is where it loses its ability to renew itself.
More than half could be transformed into savanna – within the next 30 years.
Professor Gatti said total carbon emissions are greater in the eastern part of Amazonia than they are in the western part of the region.
He said this was mostly due to spatial differences in carbon-monoxide-derived fire emissions, with the south eastern Amazonia, in particular, acting as a net carbon source to the atmosphere.
‘Over the past 40 years, eastern Amazonia has been subjected to more deforestation, warming and moisture stress than the western part, especially during the dry season, with the southeast experiencing the strongest trends,’ he said.
‘We explore the effect of climate change and deforestation trends on carbon emissions at our study sites, and find the intensification of the dry season and an increase in deforestation seem to promote ecosystem stress, increase in fire occurrence, and higher carbon emissions in the eastern Amazon.
‘This is in line with recent studies that indicate an increase in tree mortality and a reduction in photosynthesis as a result of climatic changes across Amazonia.’
Professor Scott Denning, a climate scientist at Colorado State University who was not involved in the study, described it as ‘worrying.’
‘Atmospheric measurements show that deforestation and rapid local warming have reduced or eliminated the capacity of the eastern Amazonian forest to absorb carbon dioxide,’ he explained.
‘Eastern Amazon sites have warmed by as much as about 0.6 °C (1.08F) per decade during the dry season over the past 40 years.’
Through the extensive observations, they found southeastern Amazonia – about 20 per cent of the whole area – switched to being a substantial source of CO2
Professor Simon Lewis, a climate change expert from UCL, not involved in the study, told MailOnline this is yet more evidence of an urgent need to reach net zero carbon emissions as quickly as possible to prevent further damage to the climate
AMAZON BECOMING A ‘CLIMATE EMITTER’: IS THERE A SOLUTION?
With the Amazon rainforest contributing to global climate emissions, and further fuelling global warming, is there a solution?
Professor Simon Lewis, a climate change specialist from University College London thinks there is, but we must act quickly.
‘The good news is we can do something about this. Stopping deforestation and forest fires stops carbon emissions,’ he said.
‘And because rainforests partly create their own rainfall and cool the land, slowing deforestation lessens the climate impacts.
‘Beyond this, slashing carbon emissions to net zero fast will halt global heating and stop the positive feedback from getting worse.
‘The south east Amazon sink to source story is yet another stark warning that climate impacts are accelerating and will continue to do so until carbon emissions reach net zero.’
He said this increase is three times the average rate of global warming, and similar to the rate being experienced in the Arctic, adding that the future of carbon accumulation in tropical forests has ‘long been uncertain’.
He said this study shows the uncertain future often predicted, is already happening.
Climate scientist, professor Simon Lewis, from University College London, not involved in the research, told MailOnline this was a ‘truly impressive study.’
‘Measurements of carbon dioxide up through the atmosphere tell us how the whole Amazon rainforest system is changing, rather than just one part, such as how much forest is lost, or changes within intact forests,’ he said.
‘The really bad news is that the capacity of the Amazon rainforest to absorb carbon is eroding. In the south east of the Amazon the remaining forest has now flipped to a steadily increasing source of carbon to the atmosphere.’
He said deforestation and climate change drive a release of carbon from the remaining forest, further reinforcing warming.
‘I worry that without action larger areas of remaining Amazon rainforest will become a sources of carbon to the atmosphere,’ Professor Lewis told MailOnline.
‘The good news is we can do something about this. Stopping deforestation and forest fires stops carbon emissions.
‘And because rainforests partly create their own rainfall and cool the land, slowing deforestation lessens the climate impacts.
‘Beyond this, slashing carbon emissions to net zero fast will halt global heating and stop the positive feedback from getting worse.’
The findings have been published in the journal Nature.
EXTINCTION LOOMS FOR MORE THAN ONE MILLION SPECIES
Nature is in more trouble now than at any time in human history with extinction looming over one million species of plants and animals, experts say.
That’s the key finding of the United Nations’ (UN) first comprehensive report on biodiversity – the variety of plant and animal life in the world or in a particular habitat.
The report – published on May 6, 2019 – says species are being lost at a rate tens or hundreds of times faster than in the past.
Many of the worst effects can be prevented by changing the way we grow food, produce energy, deal with climate change and dispose of waste, the report said.
The report’s 39-page summary highlighted five ways people are reducing biodiversity:
– Turning forests, grasslands and other areas into farms, cities and other developments. The habitat loss leaves plants and animals homeless. About three-quarters of Earth’s land, two-thirds of its oceans and 85% of crucial wetlands have been severely altered or lost, making it harder for species to survive, the report said.
– Overfishing the world’s oceans. A third of the world’s fish stocks are overfished.
– Permitting climate change from the burning of fossil fuels to make it too hot, wet or dry for some species to survive. Almost half of the world’s land mammals – not including bats – and nearly a quarter of the birds have already had their habitats hit hard by global warming.
– Polluting land and water. Every year, 300 to 400 million tons of heavy metals, solvents and toxic sludge are dumped into the world’s waters.
– Allowing invasive species to crowd out native plants and animals. The number of invasive alien species per country has risen 70 per cent since 1970, with one species of bacteria threatening nearly 400 amphibian species.
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