Tens of thousands of fires have been scorching Brazil’s Amazon rainforest, proliferating at the fastest rate since the country’s National Institute for Space Research (INPE) started recording such data in 2013. Brazil has weathered 74,155 fires thus far this year, an 80 percent increase compared to the same period in 2018. Nearly 36,000 of them began in the last month, with satellite images indicating that more than 9,500 were ignited in the last week alone. Most have been ignited in the Amazon. This, clearly, is not normal. But how not normal is it?

What’s causing the fires?

Environmental organizations and agencies in the country say that people have been responsible for a majority of the fires. A senior scientist at the INPE told CNN that humans had either purposefully and inadvertently set 99 percent of the fires. Farmers and loggers generally clear the land with fire during Brazil’s dry season, which runs through the summer and into early fall, for agricultural purposes. Brazilian officials have been claiming that the fires are largely a product of dry seasonal conditions, but experts and environmentalists say that explanation would not account for fires on such a huge scale.

Why have the fires been so extreme this year?

Brazil’s far-right, pro-business president Jair Bolsonaro pledged to develop the Amazon region when he took office in January. As part of those efforts, Bolsonaro has enthusiastically encouraged farmers to clear the land with fire, as well as weakened regulations meant to preserve forests and indigenous lands. His failure to abide by the Paris climate accord and reduce deforestation led Germany and Norway to cut off tens of millions of dollars in aid. Bolsonaro has also hamstrung environmental agencies charged with protecting the rainforest, cutting budgets and dismissing INPE’s director. That director warned about the high rate of deforestation, up 88 percent in June compared to the same period last year. Deforestation can make the region more arid since trees help move water from the soil into the atmosphere, which is crucial for distributing rain throughout the region. The drier conditions, which are also result of rising global temperatures, in turn increases the risk of forest fires.

How much forest is being destroyed?

Over the course of Bolsonaro’s first term, Brazil has lost 1,330 square miles of forest, a 39 percent increase compared to last year. The INPE reported that the Amazon lost 870 square miles of forest—more than half the size of Rhode Island—in July alone.

When will the fires be put out?

Unclear. Bolsonaro told reporters on Thursday that Brazil is not equipped to fight the fires—this just weeks after telling donors that he did not need aid to deal with the crisis. “The Amazon is bigger than Europe, how will you fight criminal fires in such an area? We do not have the resources for that,” he said. Rodrigo Maia, the speaker of Brazil’s lower house, said he would form an external committee to “to evaluate the situation and propose solutions to the government.”

Are they really turning the sky black?

Yes. Winds from a cold front in the region this week fanned the flames and left huge clouds of smoke hanging over major cities. The smoke and a thunderstorm engulfed Sao Paulo, Brazil’s largest city, in darkness for an hour at around 3 p.m. on Monday.

🌎Just a little alert to the world: the sky randomly turned dark today in São Paulo, and meteorologists believe it’s smoke from the fires burning *thousands* of kilometers away, in Rondônia or Paraguay. Imagine how much has to be burning to create that much smoke(!). SOS🌎 pic.twitter.com/P1DrCzQO6x — Shannon Sims (@shannongsims) August 20, 2019

How have Brazil’s leaders responded?

Not well. Bolsonaro has indulged in conspiracy theories, suggesting without evidence that non-governmental organizations are setting the fires in order to hurt his reputation. “The fire was started, it seemed, in strategic locations,” he said, according to the Washington Post. “There are images of the entire Amazon. How can that be? Everything indicates that people went there to film and then to set fires. That is my feeling.” He’s similarly claimed that researchers are manipulating deforestation data gathered by satellites as a way to attack his pro-business agenda.

How has this been affecting people in and around the Amazon?

About 1 million indigenous people live in the Amazon, and now their homes are under threat.

Representatives from indigenous reserves are reporting that the fires are ruining the crops, animals, and river systems they rely on to survive. The fires are also releasing toxic gases, such as carbon monoxide, and sending many to the hospital for respiratory issues.

What are the long-term consequences—for Brazil and for everywhere else?

The Amazon is crucial to stemming global climate change, as it absorbs carbon dioxide and releases oxygen. The Amazon itself is responsible for consuming a quarter of the 2.4 billion metric tons of carbon that forests around the world remove from the atmosphere every year. A decimated Amazon would make it extremely difficult to meet the goal of keeping worldwide warming below 3.6 degrees, as outlined in the Paris climate accords. The fires further emit greenhouse gases in the air, though it’s too early to predict the quantity and impact. As the world’s largest tropical rainforest, the Amazon is home to 30 percent of the world’s plant and animal species according to some estimates, and fires are a threat to the region’s biodiversity.