View of Brazil from the Global Forest Watch map. Pink and gold spots represent recent tree cover loss alerts.

Seeking reality in Brazil’s forests.

Camellia Williams
Aug 16 · 7 min read

As the clouds roll away at the end of Brazil’s wet season, loggers, miners and ranchers move in to stake their claims. The start of the dry season has always coincided with a spike in forest loss, and this year is no exception. What is different this year is the fierce debate that’s erupted over the data.

Headlines in July 2019 announced a huge spike in deforestation. They quoted data from Brazil’s space research agency, INPE, and their monthly deforestation alert system called DETERS. But the data was quickly criticised by Brazil’s President, Jair Bolsonaro. He told foreign journalists that the data “doesn’t relate to the reality.” He says it’s a lie. But is it? And what is the reality?

Let me show you how Global Forest Watch, an alternative forest monitoring system, can help us understand what’s happening in Brazil. Using interactive maps and dynamic data dashboards, we can see where tree cover loss is happening in almost real-time. We’ll begin with a review of the different forest monitoring systems before taking a deeper dive into the Global Forest Watch map. When we do, you’ll begin to see that it’s hard to hide from the truth.

Different systems for different uses.

Bolsonaro’s ministers have questioned the accuracy of the DETER system at detecting deforestation. To assess its accuracy we need to know more about it.

DETER uses images from the Sino-Brazilian Land Resources Satellite (CBERS-4) and the Indian Remote Sensing Satellite (IRS) to detect changes in forest cover. Thick cloud cover can ‘hide’ deforestation from satellites, which means it’s not always reported in the month it begins. This can lead to big leaps in reported deforestation, like the one in June.

Because the system only reports what it can detect that month, it shouldn’t be used to calculate a definitive area of forest loss. To do that you need to use data from the PRODES monitoring system that calculates forest loss on a year to year basis. That means it compares 2019 data with 2018 data, with the year running from 1 August to 31 July.

INPE are aware of the limitations of the DETER data and explicitly state on their website that the data should only be used as a tool to support surveillance and regulation. It’s primary purpose is the fast detection of new forest loss so action can be taken to stop it, if the activity is illegal.

In comparison, Global Forest Watch uses GLAD alerts to detect and report tree cover loss. GLAD uses NASA Landsat images to detect forest disturbance at 30-meter x 30-meter resolution and report it weekly. It does not calculate the area of tree cover loss. Like the DETER system, there can be a delay in reporting if there is heavy cloud cover. The system is designed to support monitoring, and users of Global Forest Watch can set up notifications that will alert them to changes in their chosen areas of interest.

Although GLAD alerts cannot be directly compared to the DETER reports, the data on Global Forest Watch does show that reports of tree cover loss were high in June and July. There were 75% more GLAD alerts in June 2019 compared to June 2018, and 106% more alerts in July 2019 compared to July 2018.

In addition to a peak of an unusually high number of GLAD alerts in April-May 2019, there have been a high number of GLAD alerts in June and June 2019. The unusually high spike in April coincides with fires in the northern state of Roraima. Global Forest Watch.

A third monitoring system, Imazon is reporting similar figures, so it seems unlikely the INPE data biased. The Director of INPE was sacked for releasing the June report, but this can’t hide the fact that tree cover loss is happening at a higher rate than in past years.

A deeper dive into the map.

We begin our exploration in Brazil’s protected areas. According to MapBiomas Alerta, 95% of the deforestation that occurred in the first three months of 2019 was “not authorised”. That includes national parks, nature reserves, and land set aside for indigenous peoples’. Places like Ituna Itatá Reserve.

Land rights at risk.

Ituna Itatá Reserve is an area set aside for the exclusive use of an uncontacted group of indigenous peoples’. No one but them can enter. And yet, GLAD alerts started reporting extensive tree cover loss in the reserve in early 2018. Activity stopped during the wet season, but began again in June 2019. Watch the timelapse in the gif below to see the full extent of this year’s tree cover loss.

A timelapse of GLAD alerts in the Ituna Itatá reserve shows the full extent of clearing between 1 June and 31 July 2019. This basemap is provided by Planet and shows the difference between disturbed and undisturbed areas. Gold patches represent the most recent GLAD alerts. Global Forest Watch. Planet Labs, Inc. “Monthly /Quarterly Mosaics.” Accessed through Global Forest Watch on 6 August.

The basemap I’ve chosen to use here is the Planet basemap: a mosaic of monthly or quarterly satellite images that show landscape changes over time. It’s a useful tool if you want to see how an area has changed and understand what’s happening. For example, a long straight line is probably a road, while a blackened, indistinct shape might indicate fire damage.

Of the 22,229 GLAD alerts reported within the Reserve since 2015, 33% of them occurred in a two month period between 1 June and 31 July 2019. Global Forest Watch puts the number of GLAD alerts into context with the help of data dashboard that plots the number of alerts each week and compares them to the same week in previous years. The Ituna Itatá area is too small for analysis but we can look at the chart for the wider area it sits within. As you can see, the number of GLAD alerts in June and July was unusually high.

The thick black line outlines the region of Senador José Porfírio, Pará, within which Ituna Itatá Reserve lies. The chart indicates that the number of GLAD alerts in July 2019 is unusually high. Global Forest Watch.

The increased tree cover loss in the state of Pará has been linked to the construction of hydroelectric dams. As the projects brought in people and money, the price of land in the surrounding areas increased. This change sparked a wave of illegal land grabs, some of which have involved violence. For example, Dilma Ferreira Silva, a local activist who campaigned for the rights of people who were displaced by the dam’s construction, was murdered alongside her husband and a friend. A local landowner was arrested for the crime.

A similar story is being repeated in other parts of Brazil. The most recent incident reported by the press occured in the Waiãpi indigenous reserve in the state of Amapá. Gold miners allegedly took over a village a few days after a local leader was stabbed to death, prompting the people living there to flee in fear.

This is the dark side of unauthorised forest loss. Homelessness. Intimidation. Murder. It’s not only nature that suffers, but humans too.

Slash. Burn. Sell.

So where else is forest loss happening in Brazil? And what other reasons for deforestation are there? Looking to the north of Brazil, in Roraima state, we can see a big pink patch of GLAD alerts. The data dashboard for the state also shows us a spike in fire alerts, which have been confirmed by news reports. Protected and non-protected areas alike have been affected by fire, and some may have been started on purpose.

Overlay of indigenous land rights, protected areas and GLAD alerts. Fires can cross into protected areas, leaving them vulnerable to illegal land grabs. Global Forest Watch.

As reported by The Intercept and Mongabay, deliberate fires are set by people who want to take land that isn’t theirs. By clearing trees and sowing fast-growing grass seeds, land grabbers will use the new pastures as ‘proof’ of ownership and land use. This land will then be sold on to cattle ranchers and mining organisations, who may be unaware of how the land was occupied. Not all fires in Brazil are started with the intention of claiming land, but fire alerts should be investigated when they happen unexpectedly.

Lungs of the Earth.

Brazil is the world’s fifth largest country and more than 50% of its land is covered with forest, most of it intact and pristine. The Amazon alone is the world’s largest rainforest. Every year it absorbs a quarter of all the carbon that’s taken up by forests. Keeping the Amazon intact will help the fight against climate change — and Brazil’s government has a very important role to play.

Unfortunately, Bolsonaro has publicly pledged to remove environmental protections and weaken indigenous peoples’ land rights. Bolstered by this pledge, land grabbers started taking land before Bolsonaro even took office. Now, the environment agency is being told to issue less fines to those who break the law, giving more incentive to those who want to clear Brazil’s forests. This means protections, like those on Ituna Itatá are unlikely to be enforced.

With Brazil’s environment under attack, the responsibility of the outside world grows. Bolsonaro complains that outsiders take too much interest in Brazil’s rainforests, but when they are so important to the health of the planet, that interest is justified. In 2016, most of the world’s governments made a commitment to keep the rise in global temperature below 2C above pre-industrial levels. This means they have to work together and support one another in reducing carbon emissions. Brazil alone cannot save the world, but it does need to work in collaboration with the global community.

Aided by Global Forest Watch, journalists, researchers, and citizens alike can report what’s happening in our forests. They can raise awareness and hold businesses and governments to account. Satellite imagery can’t stop illegal deforestation, but it does make it more transparent. No matter where forest loss occurs, we can see it with Global Forest Watch. And that’s the beauty of open data — no one can hide from reality.

Vizzuality Blog

Posts on data design, user research, open data, and software development. We create tools and applications with a lasting benefit to society and the environment.

Camellia Williams

Written by

Lead Writer at Vizzuality.

Vizzuality Blog

Posts on data design, user research, open data, and software development. We create tools and applications with a lasting benefit to society and the environment.

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