The Amazon is being shrouded in plumes of smoke as fires rage across parts of the rainforest, imperilling the so-called “lungs of the planet” and the vast array of life to which it is home.

Visible from outer space, the smoke billows have prompted international alarm, calls for action and much finger-pointing over what, or who, is responsible for the burning.

Brazilian President Jair Bolsonaro, in particular, has come under intense scrutiny for his controversial stewardship of Brazil’s majority share of the rainforest.

Al Jazeera answers some of the major questions being asked about the crisis in the Amazon, one of Earth’s greatest natural treasures.

Where are the fires?

The fires are burning across a range of states in Brazil’s section of the Amazon rainforest.

Northerly Roraima down through Amazonas, Acre, Rondonia and Mato Grosso do Sul have all been badly affected.

Brazil’s National Institute for Space Research (INPE) spotted more than 9,500 new forest fires in Brazil since August 15 alone, while atmospheric monitoring agencies have tracked smoke from the Amazon region drifting thousands of kilometres across the Latin American giant to the Atlantic coast and Sao Paulo, briefly turning daytime in Brazil's biggest city to night on Monday.

Amazonas, Brazil’s largest state, declared a state of emergency on August 9 while Acre has been on environmental alert since August 16 due to the fires.

Several other countries in the Amazon region, including Bolivia and Peru, which both border Brazil, have also seen a surge in fires this year, according to INPE data.

How many?

The INPE recorded nearly 73,000 fires in Brazil between January and August this year – the highest since INPE records began in 2013 and a more than 80 percent bump on the figure for the same period last year. Most of them were in the Amazon.

Meanwhile, as of August 16, a NASA analysis suggested that “total fire activity across the Amazon basin has been close to the average in comparison to the past 15 years”. NASA noted that the Amazon spreads across several countries.

It also added, “though activity appears to be above average in the states of Amazonas and Rondonia, it has so far appeared below average in Mato Grosso and Para”.

What’s causing them?

Fires are a regular and natural occurrence in the Amazon at this time of year, during the dry season.

But environmentalists and non-governmental organisations have attributed the record number of fires to farmers setting the forest alight to clear land for pasture and to loggers razing the forest for its wood, with INPE itself ruling out natural phenomena being responsible for the surge.

Critics say far-right President Bolsonaro's weakening of Brazil's environmental agency, IBAMA, and push to open up the Amazon region for more farming and mining has emboldened such actors and created a climate of impunity for those felling the forest illegally.

Recent evidence appears to bear that out with preliminary data showing deforestation in the Brazilian Amazon is skyrocketing under Bolsonaro’s watch.

The rate of forest destruction soared more than 278 percent in July compared with the same month a year ago, according to research by the Amazon Environmental Research Institute. Previously, INPE pegged the rate of deforestation in June at 88 percent higher than during the corresponding month in 2018.

“These statistics speak to who is in power and what he (Bolsonaro) is doing to undermine environmental protection ... and open the floodgates to illegal and destructive behaviour,” said Christian Poirier, Brazil programme director for NGO Amazon Watch.

Bolsonaro’s government, meanwhile, has offered a range of explanations for the blazes – including increased drought and the president himself making unfounded claims that NGOs had started the fires in an attempt to undermine his administration after it slashed their funding.

On Friday, Bolsonaro said he had authorised the use of troops to help contain the blazes and stop illegal deforestation, but he also blamed the weather for the fires.

Why does the Amazon matter?

The Amazon is the largest tropical forest in the world, covering more than five million square kilometres across nine countries: Brazil, Bolivia, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname and Venezuela.

It acts as an enormous carbon sink, storing up to an estimated 100 years worth of carbon emissions produced by humans, and is seen as vital to slowing the pace of global warming.

“The Amazon is the most significant climate stabiliser we have, it creates 20 percent of the air we breathe and it also holds 20 percent of the fresh flowing water on the planet,” Poirier said.

Put simply, he added, preserving the forest is of "critical importance" for both the region it encompasses and the rest of the world.

But in the last half-century alone, nearly 20 percent of the forest has disappeared.

Scientists have warned that if tree loss in the Amazon were to pass a certain "tipping point", somewhere between 25 and 40 percent, deforestation could start to feed on itself and lead to the demise of the forest within a matter of decades.

“One of the cornerstones of climatic stability on our planet is in peril and the consequences of this are almost too large to fathom,” Poirier said. “The future of our civilisation depends on its integrity.”

Who (and what) calls the Amazon home?

The Amazon has been inhabited by humans for at least 11,000 years and is home to more than 30 million people – about two-thirds of whom live in cities carved out of the greenery.

Among those living in the region are about one million indigenous people who are divided into some 400 tribes, according to indigenous rights group Survival International.

Most live in villages, though some remain nomadic, with each tribe possessing its distinct language and culture, both of which are traditionally intimately intertwined with the surrounding environment.

Jonathan Mazower, a spokesman for Survival International, said the tribes were “dependent on their forests for everything, and have managed and looked after them for millennia”.

“[But] many are seeing their lands burned in front of their eyes, and with it their livelihood, source of food, medicines, and their very homes,” he added.

Poirier agreed, saying the fires pose an “affront” to the “safety and integrity” of their way of life.

“Indigenous people are on the frontline of this struggle – the work they do to protect the forest is so vital and their connection to the forest is so important to their cultures,” he added.

“The potential is here for not just environmental devastation, but also cultural genocide.”

In addition to the human presence within the Amazon, the forest also houses 10 percent of all known wildlife species, according to the World Wide Fund for Nature (WWF), with a “new” species of animal or plant discovered in the rainforest every three days on average.

How has the world reacted?

The response to the fires is predominantly with a chorus of concern and condemnation of Bolsonaro’s environmental stewardship.

French President Emmanuel Macron and Irish Prime Minister Leo Varadkar said separately on Friday they would move to veto a landmark European Union trade deal brokered with South American bloc Mercosur unless Brazil takes action to protect the rainforest.

The pact requires the Latin American giant to abide by the Paris climate accord, which Bolsonaro has threatened to leave, and also aims to end illegal deforestation, including in the Brazilian Amazon.

Macron also called for the fires to be front and centre of the agenda for this weekend’s G7 summit, branding the blazes an “international crisis”.

“Our house is burning. Literally. The Amazon rainforest – the lungs which produce 20 percent of our planet’s oxygen – is on fire. It is an international crisis. Members of the G7 Summit, let’s discuss this emergency first order in two days!” Macron tweeted on Thursday.

This was echoed by German Chancellor Angela Merkel, who said the Amazon fires posed an “acute emergency” and belonged on the G7’s agenda, despite Brazil not being a member of the group.

However, Macron’s comments earned a swift rebuke from Bolsonaro, who called the issue an “internal matter” and said the French leader's suggestion evoked “a colonialist mentality that is out of place in the 21st century”.

The spat came after Norway and Germany earlier this month halted millions of dollars of Amazon protection subsidies to the Amazon Fund, accusing Brazil of turning its back on the fight against deforestation.

Meanwhile, social media users around the world have latched on to #PrayForAmazonia and #PrayForAmazon, pushing the topic towards the top of Twitter’s global trends earlier this week.

Public demonstrations are planned in Brazil’s major cities for Friday, mirroring protests held earlier in the day in several cities around the world.

“The outpouring of concern, grief and anger is unprecedented – what this is creating is a lasting impression for people that the Amazon is absolutely essential to our future and we all have a responsibility to protect it, contrary to what Bolsonaro may say,” Poirier said.

“But we can’t allow ourselves to fall into despair, there’s no other way, we have to act – we have a responsibility to ourselves, to future generations and to other beings on this planet, are of which are suffering today as a result of this chaos.”

•Text (excluding headline) courtesy of Al Jazeera. The Amazon is the largest tropical forest in the world, covering more than 5m square km [Ueslei Marcelino/Reuters]

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