A curtain of smoke from wildfires in the Amazon rainforest is spreading across Brazil, making its way to Sao Paulo and possibly heading toward neighboring countries Argentina and Paraguay.
There were 28,697 fires reported in the Amazon region in August, 38% higher than the 10-year average, WWF-Brasil said, citing data from the National Institute for Space Research known as Inpe. The number exceeds 50,000 in the year to Aug. 27, the most since 2010, it said.
Toxic particles smothered the capital Brasilia earlier this week and now have spread to Sao Paulo, the country's financial center and Latin America's biggest city. Blazes have been reported in the Pantanal wetlands and throughout the countryside of Sao Paulo state, while fire in the nation's sugar-cane fields, the world's top exporter, is set to impact the global supply of sweetener.
This is the second straight year of extreme drought in Brazil and dry, hot weather has created ideal conditions for wildfires to spread across large areas. Most of the Amazon outbreaks have been sparked by farmers and ranchers deliberately setting forest fires to create pasture field, according to Rafael Franca, a climate professor at the University of Brasilia.
There is no relief in sight as the rainy season isn't expected to begin until October, meaning conditions this month will probably be even worse.
"The situation is serious," Franca said, adding that the next months will be critical. "The only effective mechanism to dissipate all this smoke is rain, only rain."
Some 167 municipalities have declared a state of emergency due to the fires, according to the National Confederation of Municipalities. The National Meteorology Institute, known as Inmet, has issued a risk warning because most of the country's federal states have dangerously low humidity.
Temperatures topping 35C (95F) and strong winds of 60 kph (37mph) are expected in Sao Paulo state this weekend, according to a note from the Emergency Management Center of the Civil Defense of Sao Paulo. Higher levels of carbon dioxide increase respiratory illnesses and cardiovascular risks. The thick smoke can decrease visibility, affecting road traffic and airport operations.
The smoke is currently moving south toward Rio Grande do Sul state, according to Maria Clara Sassaki, a weather specialist at Tempo OK, a meteorological consultancy in Sao Paulo. It could reach as far as Paraguay and Argentina, said Alexandre Nascimento, a partner at Nottus, a weather consultancy.
"The fires are serious and indicate that there is a large area being destroyed," Sassaki said. "The smoke cloud coming from the north is probably meeting other smoke clouds on its way, increasing the concentration of pollutants even more."