Massive fires in the Amazon basin look more apocalyptic than ever this summer, with endless vistas of flames visible from the air and a shroud of smoke darkening Sao Paulo. Just yesterday, world leaders at the G7 summit committed $20 million to help stop the fires and protect the “Lungs of the Planet,” so called because the region supplies 20% of the Earth’s oxygen.

Matthew Hansen geographical science professorWhile the fires are grabbing more attention now, and even sparked a war of words between the presidents of France and Brazil, many estimates for the year-over-year increase—some exceeding 50%—seem to be overstated, said Matthew Hansen, a professor of geographical sciences who, working with NASA, leads comprehensive satellite mapping projects of earth’s vegetation and forests.

The fact that the fires may only be marginally worse than normal is no cause for celebration, Hansen said. Instead, he told Maryland Today, it’s further indication that huge expanses of the Amazon forest are destroyed every year, with the potential for grave consequences to Earth’s climate and ecosystem.

What’s the situation right now in the Amazon with these wildfires?
The first thing is that they’re not wildfires. Almost all of the fires have been set, so they’re anthropogenic in origin. A minority are actually in the rainforest. They’re in the rainforest biome, but they’re not all rainforest fires. Why are they so prevalent this year?  There are a number of factors that are making the fires this year newsworthy, particularly the impacts of smoke across the populated south of Brazil.

Who is setting the fires, and why?
The vast majority look like maintenance fires set on already cleared land, which farmers might be burning to reduce vegetation cover in expanding land use, pastures in most cases. And some of it is pretty inscrutable—sometimes it’s probably escaped fires. For example, you might see a big fire in the west near [Brazil’s] border with Bolivia, and you can pretty much infer that it started down on a pasture on a ranch, and then up an escarpment and burned a huge area of grassland in a park.

Why does the increase in fires matter this year?
I don’t mean this as a redirect, but I want to separate out the idea that this is some kind of super anomalous year from the fact that this is actually part of a larger trend. With Brazil, for instance, they had done a good job up until about 2008 reducing the rate of deforestation, but since then, it’s increased year on year. So, when we look at all the fires, it is part of an ongoing trend of increased forest loss.

So is this actually a normal year?
Our data show that through the end of July, there’s an increase in rainforest loss, but it’s not a 50, 60, 70% increase as you hear when all active fires are mentioned—our preliminary data show a 20-30% increase in rainforest loss, which includes loss due to fires. Overall, fires inside standing rainforest are similar to recent years, the difference being that most have occurred in the last few weeks, leading to a concentrated spike in emissions. Again, we have an increasing trend of rainforest loss in recent years, not a single story, and while a trend may not be as newsworthy as people in Sao Paulo breathing in smoke, it points to the fact that deforestation is advancing every year. We just don’t see it on TV like we are now.

Are you surprised this has become a political issue?
It does surprise me. [Brazilian President Jair] Bolsonaro is trying to politicize the satellite record, which is a discipline that combines engineering and science to produce what we accept are objective reference data for decisions on policy. It was really disappointing that he tried to cast the Brazilian space agency, which is a leader in this type of analysis, as a political actor. Besides, Bolsonaro’s policy is to maximize development, and the satellite shows that he’s actually doing that. So what’s the problem?  He can’t have it both ways.