Deforestation alerts in the Brazilian Amazon fell about 36 percent in the 12 months through July, to 2,874 square kilometers, the lowest total since 2013 and a figure that puts Brazil on course for its lowest official clearing rate on record.
The figure comes from Deter, the near-real-time satellite system operated by Brazil's National Institute for Space Research, known as Inpe. The total is 55.6 percent below the average of the preceding decade, according to the institute's data.
Deter is designed to direct enforcement agents to new clearings quickly rather than to produce a definitive count. Brazil's official annual deforestation rate comes from a separate Inpe system, Prodes, which uses higher-resolution imagery and is typically published in October or November.
Observatório do Clima, a Brazilian climate policy network, said that if Prodes confirms the Deter decline, Brazil is likely to record its lowest official deforestation rate since satellite monitoring began in 1988. The organization said improvements to Deter in recent years have made it a better predictor of the annual figure than it once was.
The reduction prevented the release of 2.238 billion metric tons of carbon dioxide equivalent, roughly Brazil's gross emissions in a single year, according to calculations by Seeg, an emissions estimation project run by Observatório do Clima and produced by the Amazon Environmental Research Institute.
Deforestation has fallen in each full year of President Luiz Inácio Lula da Silva's third term. His government has expanded enforcement operations, resumed demarcation of Indigenous territories and signed agreements with municipalities where clearing is concentrated. Brazil has committed to ending illegal deforestation by 2030.
"This shows that the political will to fight deforestation has prevailed," Ane Alencar, science director at the Amazon Environmental Research Institute, said in a statement in July, referring to first-half figures that showed a 38 percent decline.
Ms. Alencar said at the time that falling deforestation did not mean the forest was secure. Fire accounted for an estimated 60 percent of primary forest loss in the Brazilian Amazon in 2024, and climate scientists have warned that a strong El Niño could produce a difficult fire season even where clear-cutting remains low.
Alerts also fell in the Cerrado, the tropical savanna that has absorbed much of Brazil's agricultural expansion. Deter registered 5,119 square kilometers there, down 7.8 percent from the previous year and the lowest total in five years.
Separately, Inpe released consolidated Prodes figures for three other biomes covering August 2024 to July 2025. Deforestation fell 34.3 percent in the Caatinga, to 2,290 square kilometers; 15.3 percent in the Atlantic Forest, to 402 square kilometers; and 41.7 percent in the Pampa, to 305 square kilometers.
The Prodes figure for the year just ended is expected before the end of 2026, which would place it within weeks of the Oct. 4 general election.
The last Prodes reading, published in 2025, recorded 5,796 square kilometers cleared in the Legal Amazon in the year to July 2025, an 11.08 percent drop and the lowest figure since 2014.
It is not clear whether Inpe has set a release date.