The Amazon region has lost 10% of its native vegetation, mostly tropical rainforest, in almost four decades, a new report says.

From 1985 to 2021, the deforested area surged from 490,000 square kilometres (190,000 square miles) to 1,250,000 square kilometres (482,000 square miles), unprecedented destruction in the Amazon, according to the Amazon Network of Georeferenced Socio-Environmental Information, or Raisg.

The numbers are calculated from an annual satellite monitoring since 1985 from Bolivia, Peru, Ecuador, Colombia, Brazil, Venezuela, Suriname, Guyana and French Guiana. The report is a collaboration between Raisg and MapBiomas, a network of Brazilian nonprofits, universities and technology start-ups.

“The losses have been enormous, virtually irreversible and with no expectation of a turnaround,” said a statement from Raisg, a consortium of civil society organisations from the region’s countries.

“The data signals a yellow light and gives a sense of urgency to the need for a coordinated, decisive and compelling international action.”

Brazil, which holds about two-thirds of the Amazon, also leads the destruction. In almost four decades, 19% of its rainforest has been destroyed, due mainly to cattle ranching expansion supported by the opening of roads. The country accounted for 84% of all forest destruction in the period.

Almost half of Brazil’s carbon emissions comes from deforestation. The destruction is so vast that the eastern Amazon has ceased to be a carbon sink, or absorber, for the Earth and has become a carbon source, according to a study published in 2021 in the journal Nature.

As of 2021, the Amazon had 74% of its area covered by tropical rainforests and 9% of other natural vegetation types. The region, with 8.5 million square kilometres, has a population of 47 million people, according to Raisg estimates.

“At least some 75 billion metric tons of carbon are stored across the Amazon,” Woods Hole Research Centre researcher Wayne Walker said. “If all that carbon ended up immediately in the atmosphere, that would be about seven times global annual emissions.”