Wildfires in Brazil's Amazonas state worsen air quality in Manaus

SAO PAULO — Smoke from wildfires disrupted daily life in Brazil's largest Amazon region city of Manaus on Friday as the country's dry season approached its peak.

The city, the capital of Amazonas state, suspended in-person work at municipal administrative offices, citing worsening air quality. Public school classes were canceled, and residents were urged to wear face masks.

The city said in a statement that the concentration of pollutants averaged 196 micrograms per cubic meter, which is considered an unhealthy level way above the normal range of about 3 to 9.

“For several days, Manaus has been affected by heavy smoke from fires in municipalities elsewhere in Amazonas state and in other states,” the city said. “The serious situation extends beyond the capital and threatens the health and quality of life of thousands of families.”

State and federal satellite data showed clusters of fire hotspots near Manaus and in southern Amazonas state, as well as near Santarem in neighboring Para state.

As of Thursday, the Brazilian Amazon had recorded about 33,556 fire hotspots this year, according to Brazil’s National Institute for Space Research. That is nearly 50% more than during the same period in 2025, though about 53% below the historical average.

Fire hotspots have shifted across the Amazon since the dry season began in June. Early in the season, they were concentrated farther north, in Roraima and Amapa states. More recently, they have increased farther south, near Manaus, in southern Amazonas state and around Santarem in Para state.

Several studies suggest El Niño’s effects on the region could be more severe in 2027, when the climate pattern may disrupt the rainforest’s next rainy season.

Officials have urged preparations for drought, heat and fires as the El Niño — a cyclical climate phenomenon that normally rises temperatures and increases drought in the Amazon — develops.

During the 2023 and 2024 El Niño, temperatures rose 2 to 4 Celsius (3.5 to 7 Fahrenheit) above the forest’s historical average. Associated with severe drought, the heat fueled the Amazon’s worst wildfires in two decades.

The Amazon, which stores vast amounts of carbon dioxide and generates atmospheric moisture that helps regulate weather far beyond South America, is a vital ecosystem for the world's climate. Most wildfires there are there are not natural but rather started by humans.

Brazil’s Environment Ministry said it had deployed fire crews and aircraft to help fight fires in Amazonas state. It also said it had notified the owners of rural properties to take steps to prevent and fight wildfires. “On-the-ground inspections are being stepped up to curb new fires and investigate the illegal use of fire,” the ministry said.

The Amazonas state government did not respond to a request for comment from The Associated Press.