New research has found that a larger part of the Amazon rainforest is at risk of crossing a tipping point where it could become a savanna-type ecosystem than previously thought. In around 40% of the rainforest, rainfall is now at a level where the forest could exist in either state- rainfall or savanna.
Based on computer models and data analysis, the research- published in Nature Communications– shows that parts of the Amazon region are currently receiving less rain than previously and this trend is expected to worsen as the region warms due to rising greenhouse gas emissions.
Rainforests are very sensitive to changes that affect rainfall for extended periods. If rainfall drops below a certain threshold, areas could shift into a savanna state.
The research team focused on the stability of tropical rainforests in the Americas, Africa, Asia and Oceania. They were able to explore how rainforests respond to changing rainfall and simulate the downwind effects of disappearance of forests for all tropical forests. By doing this, they answered two questions: “if all the forests in the tropics disappeared, where would they grow back?” and “what happens if rainforests covered the entire tropical region of Earth?”
The team ran the simulations starting with no forests in the tropics across Africa, the Americas, Asia and Australia and watched forests emerge over time in the models, which allowed them to explore the minimum forest cover for all regions.
Lead author Arie Staal, formerly a postdoctoral researcher at the Stockholm Resilience Centre and the Copernicus Institute of Utrecht University, says, “The dynamics of tropical forests is interesting. As forests grow and spread across a region this affects rainfall- forests create their own rain because leaves give off water vapour and this falls as rain further downwind. Rainfall means fewer fires leading to even more forests. Our simulations capture this dynamic.”
The team then ran the models a second time, in a world where rainforests entirely covered the tropical regions of Earth. However, in many places there is an insufficient amount of rainfall to sustain a rainforest, so in many places, the model forests shrank due to a lack of moisture. Staal says, “As forests shrink, we get less rainfall downwind and this causes drying leading to more fire and forest loss: a vicious cycle.”
Finally, the team examined what will happen if emissions keep rising this century along a “very high-emissions” scenario used by the IPCC. The team found that as emissions grow, more parts of the Amazon lose their natural resilience, become unstable and more likely to dry out and transform to a savanna-type ecosystem. Even the most resilient parts of the rainforest will shrink. This means that more of the rainforest is likely to cross a tipping point as emissions reach very high levels.
The conclusion? The smallest area that can sustain a rainforest in the Amazon contracts a substantial 66% in the high-emissions scenario.
Ingo Fetzer of the Stockholm Resilience Centre, says, “We understand now that rainforests on all continents are very sensitive to global change and can rapidly lose their ability to adapt. Once gone, their recovery will take many decades to return to their original state. And given that rainforests host the majority of all global species, all this will be forever lost.”
In comparison, the minimal and maximal extents of the rainforests of Indonesia and Malaysia are relatively stable because their rainfall is more dependent on the ocean around them than on rainfall generated as a result of forest cover.
It is important to note that the study only explored the impacts of the climate crisis on tropical forests; it did not assess the additional stress of deforestation in the tropics due to agricultural expansion and logging. It is possible then that the Amazon may cross a tipping point even sooner because of relentless deforestation in the region, encouraged by Brazilian President Jair Bolsonaro.
To mitigate deforestation of the Amazon by human impact, international and domestic actors must cooperate to find a solution. While the Bolsonaro administration has made its stance on deforestation and environmental conservation abundantly clear, the country’s decentralised federal governing system allows for a great deal of executive and legislative autonomy for Brazilian states. Individual states can break from the party line, as demonstrated during the country’s COVID-19 outbreak, when states opted to dismiss the President’s recommendations and implement their own ordinances to soften the effects of the virus. Individual states and governors will need to unite behind a common goal of slowing deforestation. Once this happens, international organisations and domestic NGOs could bypass President Bolsonaro’s protectionist policies and deal directly with the states that govern areas at risk of deforestation, by subsidising economic programmes that incentivise illegal loggers to pursue other opportunities.
The Ministry of Environment in Brazil has said that it will continue operations to restrict deforestation and fires in the Amazon and other regions. The announcement follows an earlier decision to halt such operations starting on August 31.
The decision was shared on the ministry’s website on August 28 after vice president Hamilton Mourão said Environment Minister Ricardo Salles acted “hastily” when he said the government had run out of money for operations against deforestation.
The ministry had previously said that it had been blocked from accessing over $11 million for environmental protection, which would have demobilised over 1 300 firefighters, hundreds of inspection agents, six helicopters and 10 planes. However, Mourão told reporters that no operations would be stopped despite the ministry’s statement and that Brazil would continue to work to restrict deforestation in the Amazon.
In May, president Jair Bolsonaro put the army in charge of protecting the Amazon rainforest in May, following international demands for action after wildfires in the rainforest skyrocketed recently. However, the operation proved to be a failure, as investigation and prosecution of rainforest destruction by ranchers, farmers and miners ended, even as this year’s burning season increased. Instead, the army seems to be focusing on small road-and-bridge-building projects that allow exporters to flow faster to ports and ease access to protected areas in the forest. There have also been no major raids against illegal activity since Bolsonaro required military approval for them a few months ago.
Deforestation in the Brazilian Amazon
According to data published by the Monitoring of the Andean Amazon Project (MAAP), 516 fires covering 376 416 hectares have been detected between May 28 and August 25. 83% of these fires have burned in recently deforested areas, while 12% have occurred within intact forests. 97% of the fires are illegal.
Overall, deforestation in the Amazon has risen sharply since January 2019 when Jair Bolsonaro became president. Bolsonaro promised to open the Amazon to more mining, logging and industrial agriculture. His administration has subsequently relaxed environmental law enforcement and penalties and issued executive orders opening up protected areas and indigenous lands to logging, mining and agribusiness.
The study, published in the journal, Science, observed an increasing trend in a measure called Vapour Pressure Deficit (VPD) over tropical South America in dry season months. VPD is a combined function of air temperature and relative humidity and is a critical variable in determining plant photosynthesis. Higher VPD values indicate a decline in atmospheric moisture. This implies that the Amazon is likely to increasingly struggle to sustain its water demands, triggering more widespread and severe droughts. As a result, wildfire risk and tree mortality will increase, causing a significant loss of carbon over the Amazon basin.
This has already been seen with previous droughts. After the 2005 megadrought, where more than 70 million hectares of pristine forests in southwestern Amazonia were affected, the most negative annual carbon balance ever was recorded in the region. This decrease can be attributed to extensive and severe damage to the forest canopy that was detectable by satellite. The older, larger, more vulnerable canopy trees were especially susceptible to dieback and tree falls. Even when rainfall levels recovered in the following years, about half of the forest affected by the 2005 megadrought – an area the size of California – did not recover by the time the next major drought began in 2010.
Furthermore, during the 2015 Amazonia drought, the highest VPD since 1979 was recorded. Similar values that are well beyond the scope of natural variability have been observed across the last decades, insinuating a human influence. The researchers suggest that elevated levels of greenhouse gases account for approximately half of the increase in atmospheric dryness. Other influencing factors are unclear, but burning of rainforest biomass for agriculture that causes widespread land-cover change, is thought to be another predominant cause. Satellite data taken in 2018 revealed that an area of Amazon rainforest roughly the size of a football pitch is now being cleared every single minute.
Dr Armineh Barkhordarian from the University of California and lead author of the study said, “We observed that in the last two decades, there has been a significant increase in dryness in the atmosphere as well as in the atmospheric demand for water above the rainforest. In comparing this trend to data from models that estimate climate variability over thousands of years, we determined that the change in atmospheric aridity is well beyond what would be expected from natural climate variability.”
Higher VPD levels are concerning as the Amazon rainforest- commonly coined ‘the lungs of the Earth’- is critical in regulating the global climate. The multitude of flora found in tropical forests enable them to extract half of the atmospheric carbon dioxide via photosynthesis – thus helping to reduce levels of this greenhouse gas and help mitigate global warming.
In addition, the Amazon basin plays an important role by regulating rainfall in the region. It cycles water between the forest and the atmosphere via rainfall and transpiration of leaves, leading to a freshwater ocean in South America – the rivers and groundwater – that maintains rainfall in the southern agricultural regions of the continent. However, the Amazon rainforest is extremely vulnerable to increases in atmospheric drying and warming, as they are thought to produce up to 80% of their own rainfall. A decrease in atmospheric moisture, combined with an increase in global temperatures, decreases the ability of the Amazon to regulate its rainfall, thus increasing the vulnerability of major Brazilian cities to water shortages.
Will the Amazon rainforest survive?
The dire potential situation has highlighted the need for a greater focus on halting deforestation in the Amazon basin, in conjunction with decreasing emissions of greenhouse gases. Both will help decrease VPD and hence reduce the potential risk of droughts and the associated threat of wildfires and tree mortality. It has never been more critical to address this drying out issuebecause if the Amazon forest is lost, the crucial ecosystem services it provides will also be lost.
Investing in forests to fight climate change seems like a sure bet. Trees absorb carbon dioxide from the atmosphere, pump out oxygen, and live for decades. What could go wrong? The answer, according to a newly published paper in Science, is: a lot.
Fires, rising temperatures, disease, pests and humans all pose threats to forests, and as climate change escalates, so too do these threats. While forest-based solutions need to play an important role in addressing climate change, the risks to forests from climate change must also be considered.
“Current risks are not carefully considered and accounted for, much less these increased risks that forests are going to face in a warming climate,” William Anderegg, a biologist at the University of Utah and first author of the new paper, told Mongabay.
As societies strive to meet climate goals such as those set by the Paris Agreement — which aims to limit the global temperature rise to “well below” 2° Celsius (3.6° Fahrenheit) by 2100 — interest in planting, protecting, and managing forests (strategies referred to as forest-based natural climate solutions) has grown in recent years. A number of arenas and policies such as the Trillion Tree Campaign, supported by the United Nations, as well as individual companies have also launched tree-planting initiatives.
Up to 30% of global emissions today are pulled out of the atmosphere by land-based plants. But for forests to be good carbon-removal investments, they need to be relatively permanent, meaning that the plants and soil in a forest will absorb carbon and keep it locked away for decades or centuries. What climate change does is exacerbate many of the threats to forest permanence.
“Avoiding a 2° [Celsius] or 2.5° increase in temperature will be difficult without a very robust natural carbon solution,” Daniel Nepstad, president and founder of the Earth Innovation Institute, who was not involved in the paper, told Mongabay. “The paper helps us put in perspective the realistic expectations of a forest as a climate mitigation approach.”
An estimated 44% of forests are threatened with what is known as a stand replacing disturbance such as a high-intensity fire, hurricane, or disease outbreak that would kill most or all of the mature trees in the stand. The combined effects of multiple disturbances such as both drought and disease or drought and fire also hasten forest destruction.
“Climate change is going to supercharge the risks that forests face,” Anderegg said. “We’re going to see more fires, more droughts and more pests and pathogens in a warming climate.”
The recent fires in Australia and in the Amazon served as a global wake-up call about the increasing threat of fire on a warming planet and the impermanence of forests. Fire causes an estimated 12% of stand replacing disturbances to forests worldwide, and is a particular threat in Mediterranean climates, boreal forests, Australia, and the Western U.S. In the U.S., fire risk has already doubled over the past 30 years.
Droughts also threaten forests globally. A drought in California between 2011 and 2015 killed an estimated 140 million trees and caused the state’s ecosystem to be a net source of carbon rather than a sink. The disturbance accounted for 10% of the state’s greenhouse gas emissions from that time period.
Biotic agents such as insects and plant diseases also present a huge challenge to forests and forest management. The mountain pine beetle (Dendroctonus ponderosae), for example, is responsible for the deaths of billions of trees in temperate and boreal coniferous forests. At this point, science does not have a good way of predicting where, when, and to what extent these threats will present.
Anderegg and a group of global experts gathered in 2019 to talk about natural climate solutions. Here, they asked: How can we assess the risks to forest permanence? What can science contribute to be sure forest-based solutions are good investments for the climate? And how can we get that information to land managers and policymakers?
The newly published paper in Science was one of the outcomes of that meeting. In it, the authors provide a road map for assessing risks to forest permanence. Forest plot data, remote sensing, and mechanistic vegetation modeling are highlighted as some of the best scientific tools available.
Combining long-term satellite records with forest plot data, for instance, can provide solid estimates for future forest stress and disturbance. Computer models in climate risks as well as models of tree growth and fire disturbance are also becoming more advanced.
However, because much of the forest plot data is collected in temperate forests, tropical forests have large gaps in data and monitoring. Also, many of these cutting-edge tools and techniques are not widely used outside of the scientific community, meaning policy decisions sometimes rely on science that is decades old.
The authors urge policymakers to be sure forest-based, natural climate solutions are done with the best available science. Likewise, scientists are urged to improve tools for sharing information across different groups outside of science.
Publicly available, easily usable and open-source tools to connect decision and policymakers to science and data are a priority, and something Anderegg and colleagues are currently working to create. The hope is that these tools will inform local decision-making based on current scientific understanding.
Beyond assessing risks to forests, the authors stress the importance of investing in forests in both an ecologically and socially responsible way.
“Planting native tree species and perhaps a diversity of tree species, involving local communities, and respecting indigenous communities and their rights in these forestry efforts are some of the ways to do this,” Anderegg said.
Another key point is to be mindful of how and where forests are planted. Across the high latitudes in Canada or Russia, for instance, the reflective nature of the snow cools the planet. So planting trees in these areas and covering the snow would actually tend to heat up the planet.
Finally, programs that offset carbon emissions by creating and protecting forests, while critical, should not distract from the simultaneously urgent matter of reducing fossil fuel emissions.
“There has been a tendency over the years, and it resurges every now and then, to put too much faith in forests or tree planting as a climate change solution,” Nepstad said. “First and foremost, we have to decarbonize the economy and move beyond fossil fuels, and that message has come through in this paper.”
“Keep in mind that there are lots of other reasons that we want to protect, conserve and perhaps restore forests,” Anderegg said, “such as biodiversity benefits, clean air, clean water, ecosystem services and tourism…Forests are about more than carbon.”
National and Amazon-region Indigenous federations and communities in Ecuador have launched a global campaign and have filed legal actions demanding that the flow of crude oil through Ecuador’s major pipelines be suspended. The federations are supported by Amazon Frontlines, COICA and a coalition of regional international human rights organisations.
On April 7, the country’s SOTE and OCP pipelines ruptured as a result of neglecting to address erosion on the Coca and Napo rivers. Indigenous groups affected by the spill filed a lawsuit asking for clean up, redress and an end to oil company impunity, however the court case has been indefinitely suspended since June. Erosion and massive landslides are threatening a second oil spill, which would contaminate rivers flowing into Peru and Brazil.
In light of this, Kichwa communities have filed dozens of lawsuits demanding court-ordered injunctions to immediately shut down the oil pipelines until safety is restored to the area.
Since the onset of the COVID-19 pandemic, Indigenous people have called for the suspension of all resource extraction in the Amazon. A suspension of the SOTE and OCP pipelines would equate to a suspension of all oil production in Ecuador at a time when Indigenous communities living along the pipeline are dually threatened by the pandemic and oil contamination. Half of the oil produced at these pipelines are shipped to refineries in California and Washington.
Gregorio Mirabel, General Coordinator of COICA, says, “Oil spills and poison in our rivers are caused by corporations that plunder and line their pockets and governments that promote the exploitation of resources in the Amazon Basin. When our Indigenous brothers and sisters are threatened for these reasons, we are all threatened. COICA will not let them fight alone. We are here to fight together for our rights.”
Ongoing resource extraction has accelerated the spread of COVID-19 in the world’s most biodiverse tropical rainforest. According to the Pan-American Health Organization, the virus has infectedat least 20 000 people in Indigenous communities of the Amazon. Indigenous peoples are the first line of defense for the Amazon rainforest. At the first World Assembly for the Amazon in July, Indigenous organisations from Brazil, Bolivia, Peru, Ecuador, Colombia, Venezuela, Guyana, French Guyana and Suriname called for a moratorium on extractive activities to confront toxic contamination, raging fires, loss of territory and biodiversity, climate change and, now, infection.
Mitch Anderson, Executive Director of Amazon Frontlines, says, “For too long, oil companies have acted with total impunity in Ecuador. Now, with a global pandemic raging, climate change accelerating, and the survival of thousands of Indigenous peoples at risk, it is imperative that the Ecuadorian court impose an immediate suspension of the country’s oil pipelines to avoid another disaster. It’s time to stand with Indigenous peoples, who put their own lives on the line every day to protect our planet’s best natural defense against climate change, the Amazon rainforest.”
This article comes from the frontline activities of Amazon Frontlines, whose mission it is to support indigenous peoples to defend their rights to land, life and cultural survival in the Amazon Rainforest.
Amazon Frontlines is a non-profit organisation based in Lago Agrio, Ecuador that leverages technology, legal advocacy and movement building to support indigenous peoples to defend their rights to land, life and cultural survival in the Amazon Rainforest. For more information, visitwww.amazonfrontlines.org.
Global Wildlife Conservation
GWC conserves biodiversity on Earth through the safeguarding of wildlands and wildlife protection. It engages in biodiversity exploration, habitat conservation, protected area management, wildlife crime prevention and endangered species recovery. For more information, visit https://globalwildlife.org.
A recent study has found that around half of beef exports and almost a quarter of soy exports from Brazil to the EU could be linked to illegal deforestation in two of the country’s most ecologically important regions, the Amazon and Cerraro. This could have detrimental implications for international trade agreements and efforts to combat the climate crisis.
The study, published in the journal Science, found that 2% of properties in the Amazon and Cerraro are responsible for 62% of illegal deforestation, of which a significant proportion is linked to agricultural exports. “This small but very destructive portion of the sector poses a threat to the economic prospects of Brazil’s agribusiness, in addition to causing regional and global environmental consequences,” the researchers said.
Cerrado is regarded as a ‘biodiversity hotspot’, marked by savannahs, grasslands, and forests that spans approximately 200 million hectares. Significant proportions of these important ecological areas in Brazil are being cleared to accommodate the global demand for beef by making way for cattle ranches, which are then converted to soy fields with the purpose of feeding livestock or to be exported to other countries.
The findings demonstrated that about 1.9 million metric tons of soy grown on properties with illegal deforestation reaches EU markets every year- indicating that about 22% of all soy exports from Brazil to the EU could be contaminated. The researchers noted that the true percentage may be higher as their study only covered 80% of the soy plantations, and did not sample the cumulative total.
41% of the EU’s soy imports originate from Brazil, which equates to 13.6 million metric tons per year. Between 25% to 40% of beef imports come directly from properties with illegal deforestation. The study estimates that 12% of the 4.1 million cows traded to slaughterhouses in the states of Para and Mato Grosso in 2017, came from properties potentially engaging in illegal deforestation.
However, the figure increases to about 50% when considering the suppliers that had indirect contamination with illegal deforestation- such as when a ranch does not deforest but buys cattle from one that does.
In Mato Grosso, contamination of beef exports by illegal deforestation could be as high as 44% in the Amazon and 61% in the Cerrado regions.
How Did the Researchers Conduct the Investigation?
In order to produce these figures, and draw parallels between illegal deforestation and agricultural exports, the researchers gathered land-use and deforestation data maps for Brazil as well as information on approximately 815 000 rural properties in the Amazon and Cerrado. They also examined cattle transport documents. They then developed software that calculated the level to which each property was complying with environmental and deforestation laws.
The findings of this study could have extensive implications for how countries confront trade agreements in the future knowing a portion of the imports could be associated with illegal deforestation of the Amazon.
“International buyers of Brazil’s agricultural commodities have raised concerns about products that are contaminated by deforestation,” the researchers said. “Among the concerns is that increasing greenhouse gas emissions from deforestation and forest fires in Brazil could cancel out EU climate change mitigation efforts.”
The BBC reported that ‘as the global demand for meat soars, and as China turns to Brazil for its supply of soybeans amid the trade war with the US, experts worry that Brazil’s agricultural boom will come at the cost of habitats like the Cerrado and Amazon’.
The researchers said that “all economic partners of Brazil should share the blame for indirectly promoting deforestation and greenhouse gas emissions by not barring imports and consuming agricultural products contaminated with deforestation, illegal or not.” They further noted that their investigation is an essential stepping stone in pressing Brazil ‘to conserve its environmental assets’ and encourage international efforts to mitigate greenhouse gas emissions.
Deforestation in the Brazilian rainforest is speeding up. In June 2020, it increased by 10.7% compared to the previous year. The dismantling of environmental protections and president Jair Bolsonaro’s economic policies have set the stage for environmental disaster. The international community needs to pressure Brazil into complying with its climate commitments as the country has an important responsibility in the fight against the climate crisis because of the Amazon, a fight it is currently losing.
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