satellite deforestation

Satellite pictures used to catch illegal Amazon deforesters

Image credit: reuters

Satellite imagery is being used to detect illegal deforestation activities happening in the Amazon rainforest.

Images taken in 2015 detected a fresh clearing of rainforest in an indigenous reserve and within months, authorities in Peru had evicted the wildcat miners driving the deforestation.

The eviction was considered a rare victory in a region where a gold rush has laid waste to large swathes of pristine forest.

The rapid response was possible thanks to better use of satellite technology that now allows deforestation to be tracked in near real-time, giving governments “unprecedented” opportunities to take action, said Matt Finer, the lead author of a paper on the trend.

Tropical forests are critically important for human livelihoods, climate stability, and biodiversity conservation but remain threatened.

In recent years major strides have been taken in documenting historical and annual tropical forest loss with satellites.

“On the technical side, it is critical to capitalise on continually improving satellite technology to better detect, understand, and prioritise deforestation events,” the paper states.

Instead of years passing before learning about a new deforestation hotspot, authorities can track it in weeks or months, said Finer.

“Most tropical countries now cannot say, ‘well we didn’t have the information, or we didn’t have the information on time’,” said Finer, a research specialist at the organisation Amazon Conservation, which spotted the 2015 clearing in Peru’s Amarakaeri Communal Reserve.

Satellites have gradually been capturing more frequent images of the world’s tropical forests with greater detail. In recent years, researchers at the University of Maryland developed an automated early-warning system to notify authorities of likely forest loss, said Finer.

Algorithms can further filter the data by pointing to particularly troublesome patterns, such as the loss of green forest cover inside protected reserves or lines suggesting new roads have been cut through primary rainforest, said Finer.

Daniel Castillo, the head of a team in Peru’s environment ministry that uses the technology, said finding out about deforestation early on can keep it from spinning out of control. He pointed to the expansion of illegal gold mining in southern Peru that is now a key driver of the region’s economy.

“It’s now much more complicated to control,” said Castillo. “If we can identify it early, and take corresponding actions, it can be controlled.”

The so-called GLAD (Global Land Analysis & Discovery) alerts developed at the University of Maryland now cover more than 20 countries with tropical forest, Finer said.

Peru and Brazil have also developed their own early-warning deforestation systems tailored to their needs, Finer added.

Castillo said his team analyses deforestation alerts based on Landsat images taken every 8-10 days, and passes worrisome trends on to authorities in other ministries.

“We have all the tools to be able tell when this kind of phenomenon occurs, we only really need effective action,” Castillo said.

Sign up to the E&T News e-mail to get great stories like this delivered to your inbox every day.

Recent articles