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What would happen if we cut down the entire Amazon rainforest? Could it be replaced by an equal amount of reforestation elsewhere?
Removing the entire Amazon rainforest would have myriad consequences, with the most obvious ones possibly not the worst.
Most people will first think of the carbon currently stored in the Amazon, the world’s largest rainforest. But the consequences would be far-reaching for the climate as well as biodiversity and ecosystems — and, ultimately, people.
The overall impact of the Amazon’s complete removal is unthinkable and beyond the power of our current predictive tools. But let’s look at some aspects we can describe.
The Amazon rainforest is estimated to harbour about 76 billion tonnes of carbon. If all trees were cut down and burned, the forest’s carbon storage capacity would be lost to the atmosphere.
Some of this carbon would be taken up by the oceans, and some by other ecosystems (such as temperate or arctic forests), but no doubt this would exacerbate climate warming. For comparison, humans emit about 10 billion tonnes of carbon every year through the burning of fossil fuels.
But the Amazon forest does more than store carbon. It is also responsible for the circulation of huge quantities of water.
This image, captured by NASA’s Aqua satellite in 2009, shows how the forest and the atmosphere interact to create a uniform layer of “popcorn” clouds during the dry season. It is during this period, the time without rain, that the forest grows the most.
If the Amazon’s cloud systems and its capacity to recycle water were to be disrupted, the ecosystem would tip over and irreversibly turn into dry savannah very quickly. Estimates of where this tipping point could lie range from 40% deforestation to just 20% loss of forest cover from the Amazon.
Reforestation elsewhere to achieve the same amount of carbon storage is technically possible, but we have neither the time (several hundred years would be needed) nor the land (at least an equivalent surface area would be required).
Another reason why reforestation is not a remedy is that the water the rainforest circulates — and with it the availability of nutrients — would disappear.
Once you cut the circulation of water through (partial) deforestation, there is a point of no return. The water doesn’t disappear from the planet, but certainly from the forest ecosystems, with immediate and powerful consequences for the world’s climate.
Perhaps the most drastic, and least reversible, impact would be the loss of wildlife diversity.
The number of animal species found in the Amazon is even higher, with the largest part made up by insects, representing around 10% of the known insect fauna, as well as a large but unknown number of fungi and microbes.
Once species are lost, they are lost forever, and this would ultimately be the most harmful consequence of cutting down the Amazon. It would possibly be worse than the loss of its role as a massive redistributor and storage of water and carbon.
Last but certainly not least, there are about 30 million people living in and near the Amazon rainforest.
The consequences of losing the forest as a provider of the ecosystem services mentioned above and as a source of food and habitat are unfathomable. The repercussions would reach far into global politics, the global economy, and societal issues.
With all of the burning and clearing happening in the Amazon rainforest, it was only going to be a short matter of time before a tipping point was reached and now a tipping point appears on the horizon. It would seem only a matter of 1 or 2 years before the Amazon is unable to sustain itself through rainfall. The link below is to an article reporting on the threat posed to the Amazon.
Record fires are raging in Brazil’s Amazon rainforest, with more than 2,500 fires currently burning. They are collectively emitting huge amounts of carbon, with smoke plumes visible thousands of kilometres away.
Fires in Brazil increased by 85% in 2019, with more than half in the Amazon region, according to Brazil’s space agency.
This sudden increase is likely down to land degradation: land clearing and farming reduces the availability of water, warms the soil and intensifies drought, combining to make fires more frequent and more fierce.
The growing number of fires are the result of illegal forest clearning to create land for farming. Fires are set deliberately and spread easily in the dry season.
Ironically, farmers may not need to clear new land to graze cattle. Research has found a significant number of currently degraded and unproductive pastures that could offer new opportunities for livestock.
New technical developments also offer the possibility of transforming extensive cattle ranches into more compact and productive farms – offering the same results while consuming less natural resources.
The devastating loss of biodiversity does not just affect Brazil. The loss of Amazonian vegetation directly reduces rain across South America and other regions of the world.
The planet is losing an important carbon sink, and the fires are directly injecting carbon into the atmosphere. If we can’t stop deforestation in the Amazon, and the associated fires, it raises real questions about our ability to reach the Paris Agreement to slow climate change.
The Brazilian government has set an ambitious target to stop illegal deforestation and restore 4.8 million hectares of degraded Amazonian land by 2030. If these goals are not carefully addressed now, it may not be possible to meaningfully mitigate climate change.
Since 2014, the rate at which Brazil has lost Amazonian forest has expanded by 60%. This is the result of economic crises and the dismantling of Brazilian environmental regulation and ministerial authority since the election of President Jair Bolsonaro in 2018.
Bolsonaro’s political program includes controversial programs that critics claim will threaten both human rights and the environment. One of his first acts as president was to pass ministerial reforms that greatly weakened the Ministry of the Environment
Regulations and programs for conservation and traditional communities’ rights have been threatened by economic lobbying.
Over the last months, Brazil’s government has announced the reduction and extinction of environmental agencies and commissions, including the body responsible for combating deforestation and fires.
Although Brazil’s national and state governments are obviously on the front line of Amazon protection, international actors have a key role to play.
International debates and funding, alongside local interventions and responses, have reshaped the way land is used in the tropics. This means any government attempts to further dismantle climate and conservation policies in the Amazon may have significant diplomatic and economic consequences.
For example, trade between the European Union and South American trading blocs that include Brazil is increasingly infused with an environmental agenda. Any commercial barriers to Brazil’s commodities will certainly attract attention: agribusiness is responsible for more than 20% of the country’s GDP.
Brazil’s continued inability to stop deforestation has also reduced international funding for conservation. Norway and Germany, by far the largest donors to the Amazon Fund, have suspended their financial support.
These international commitments and organisations are likely to exert considerable influence over Brazil to maintain existing commitments and agreements, including restoration targets.
Brazil has already developed a pioneering political framework to stop illegal deforestation in the Amazon. Deforestation peaked in 2004, but dramatically reduced following environmental governance, and supply change interventions aiming to end illegal deforestation.
Moreover, private global agreements like the Amazon Beef and Soy Moratorium, where companies agree not to buy soy or cattle linked to illegal deforestation, have also significantly dropped clearing rates.
We have financial, diplomatic and political tools we know will work to stop the whole-sale clearing of the Amazon, and in turn halt these devastating fires. Now it is time to use them.
The effects of European consumption are being felt in Brazil, driving disastrous deforestation and violence.
But the destruction can end if the European Union demands higher environmental standards on Brazilian goods. Hundreds of scientists and Indigenous leaders agree: the time to act is now, before it’s too late.
In an open letter published today in the journal Science, more than 600 scientists from every country in the European Union (EU) and 300 Brazilian Indigenous groups asked the EU to demand tougher standards for Brazilian imports.
The letter calls on the EU to ensure a trade deal with Brazil respects human rights and the natural world.
Crucially, this can be done without harming Brazil’s agriculture, if already cleared land is used to its full potential. Indeed, in the long term, farming in the region depends on the rains brought by healthy forests.
Brazil’s Indigenous people and the forests they protect are facing annihilation.
Controversial president Jair Bolsonaro is opening the Amazon rainforest to business and threatening Indigenous people who stand in the way. In his first hours in office, Bolsonaro gave power over Indigenous land to the Ministry of Agriculture, which is widely seen to be controlled by corporate lobbyists.
As Bolsonaro scraps environmental laws, forests are being cut down faster than they have been in years. And the EU is helping drive this carnage: more than a football field of Brazilian rainforest is cut down every hour to produce livestock feed and meat for Europe.
Although the situation may seem dire for the Amazon and its inhabitants, ongoing trade talks provide a chance to act.
Billions of euros flow to Brazil from business with the EU, its second-largest trade partner. Goods flowing in the other direction include environmentally and socially destructive livestock feed (usually soy grown on deforested land) which enters the EU on a tariff-free basis. Right now, European consumers have no way of knowing how much blood is actually in their hamburger. The ongoing EU-Brazil trade talks are therefore a powerful opportunity to curb Bolsonaro’s appetite for destruction.
It is hard to overstate the case for strong action from Europe. People in Brazil – especially Indigenous and local communities – are being violently repressed when trying to defend their land against agricultural and mining companies.
This violence has reached record levels under Bolsonaro, with at least nine people murdered so far in April 2019. And genocide is a real possibility if nothing is done to protect Indigenous people and their land.
Alarmingly, Bolsonaro has even said:
It’s a shame that the Brazilian cavalry hasn’t been as efficient as the Americans, who exterminated the Indians.
On top of the horrifying assault on Brazil’s original inhabitants, demolishing the country’s forests, savannas and wetlands would have devastating consequences for the world.
If the Amazon rainforest alone is destroyed, the resulting carbon emissions could make it extremely difficult to limit global warming to less than two degrees. Burning fossil fuels is often seen as the only culprit in climate breakdown, but tropical deforestation is the second-largest source of carbon emissions in the world.
Even losing part of the Amazon could cause a tipping point where the forests no longer create enough rain to sustain themselves. This would cause droughts that would drive many species to extinction, devastate farming in the region and likely cause further violence.
We are not just at an ecological tipping point, but a social one, too. The world is waking up to the risks posed by destroying our climate and natural world. Climate change is considered the number one security threat by Brazilian people and by many European nations.
Europeans believe neither their country nor the EU is doing enough to protect our planet’s life support systems. As protests flare up in Europe over environmental crises, climate change will be a key issue in the upcoming European elections.
As scientists, we use emotive words carefully. But our open letter calls on the EU to take urgent action because we are terrified of the consequences of Brazilian deforestation, both locally and globally.
We beg the EU to stand up for its citizens’ values and our shared future by making sure trade with Brazil protects, rather than destroys, the natural world on which we all depend.
The link below is to an article that looks at deforestation of the Amazon in Peru for more gold mining.
This year, I was on the judging panel for the Royal Statistical Society’s International Statistic of the Decade.
Much like Oxford English Dictionary’s “Word of the Year” competition, the international statistic is meant to capture the zeitgeist of this decade. The judging panel accepted nominations from the statistical community and the public at large for a statistic that shines a light on the decade’s most pressing issues.
On Dec. 23, we announced the winner: the 8.4 million soccer fields of land deforested in the Amazon over the past decade. That’s 24,000 square miles, or about 10.3 million American football fields.
This statistic, while giving only a snapshot of the issue, provides insight into the dramatic change to this landscape over the last 10 years. Since 2010, mile upon mile of rainforest has been replaced with a wide range of commercial developments, including cattle ranching, logging and the palm oil industry.
There are a number of reasons why this deforestation matters – financial, environmental and social.
First of all, 20 million to 30 million people live in the Amazon rainforest and depend on it for survival. It’s also the home to thousands of species of plants and animals, many at risk of extinction.
Second, one-fifth of the world’s fresh water is in the Amazon Basin, supplying water to the world by releasing water vapor into the atmosphere that can travel thousands of miles. But unprecedented droughts have plagued Brazil this decade, attributed to the deforestation of the Amazon.
During the droughts, in Sao Paulo state, some farmers say they lost over one-third of their crops due to the water shortage. The government promised the coffee industry almost US$300 million to help with their losses.
Finally, the Amazon rainforest is responsible for storing over 180 billion tons of carbon alone. When trees are cleared or burned, that carbon is released back into the atmosphere. Studies show that the social cost of carbon emissions is about $417 per ton.
Finally, as a November 2018 study shows, the Amazon could generate over $8 billion each year if just left alone, from sustainable industries including nut farming and rubber, as well as the environmental effects.
Some might argue that there has been a financial gain from deforestation and that it really isn’t a bad thing. Brazil’s president, Jair Bolsonaro, went so far as to say that saving the Amazon is an impediment to economic growth and that “where there is indigenous land, there is wealth underneath it.”
In an effort to be just as thoughtful in that sense, let’s take a look. Assume each acre of rainforest converted into farmland is worth about $1,000, which is about what U.S. farmers have paid to buy productive farmland in Brazil. Then, over the past decade, that farmland amounts to about $1 billion.
The deforested land mainly contributes to cattle raising for slaughter and sale. There are a little over 200 million cattle in Brazil. Assuming the two cows per acre, the extra land means a gain of about $20 billion for Brazil.
Chump change compared to the economic loss from deforestation. The farmers, commercial interest groups and others looking for cheap land all have a clear vested interest in deforestation going ahead, but any possible short-term gain is clearly outweighed by long-term loss.
What if someone wanted to replant the lost rainforest? Many charity organizations are raising money to do just that.
At the cost of over $2,000 per acre – and that is the cheapest I could find – it isn’t cheap, totaling over $30 billion to replace what the Amazon lost this decade.
Still, the studies that I’ve seen and my calculations suggest that trillions have been lost due to deforestation over the past decade alone.
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