Air quality at half mast in São Paulo and Rio de Janeiro, sunsets reddish orange due to pollution: smoke from intense forest fires in the Amazon and other regions is spreading across Brazil, reaching neighboring countries.
Nearly five million km2 were affected by smoke in Brazil, about 60% of the territory, according to estimates from satellite images by Karla Longo, a researcher at the National Institute for Space Research (INPE).
“If we take into account the areas affected in neighbouring countries and in the Atlantic Ocean, the area affected on Sunday was of the order of ten million km2 “, the researcher said in an email sent to AFP on Monday.
Argentine and Uruguayan authorities have reported the presence of this smoke in several of their regions.
São Paulo (southeast of Brazil), the largest city in Latin America, repeatedly topped the ranking of the most polluted major cities in the world on Monday, according to the air quality monitoring company IQAir.
The level of fine particles (PM2.5) reached 69 micrograms per cubic meter, almost 14 times higher than the limit recommended by the World Health Organization (WHO).
“The air is very dry, very polluted. You can barely breathe, it’s suffocating,” laments Ieda Bandeira, a 76-year-old pastry chef, who says she “drinks a lot of water and puts wet clothes out the windows” to alleviate the dryness.
Breathing problems
The situation is also worrying in Rio de Janeiro, where the level of fine particles stands at 26 micrograms per cubic meter, more than five times the WHO threshold.
In many Brazilian cities, health authorities are reporting a sharp increase in cases of people suffering from respiratory problems, asthma attacks, pneumonia or sinusitis.
“Every day in the afternoon the sun turns orange and the sky is very dark because of the smoke,” describes Jaqueline Almeida, 23, a resident of São Paulo.
These fires, most of which are of criminal origin according to the authorities, and often linked to agricultural activity, are spreading more easily due to a historic drought caused in particular by global warming, according to experts.
Smoke carried by the wind
Satellite images from the US National Oceanic and Atmospheric Administration (NOAA) clearly showed a thick cloud of gray smoke along the Andes mountain range towards the south of the continent on Monday.
This phenomenon is due to “the wind which channels the smoke towards the south”, explains to AFP the meteorologist Estael Sias, from the forecasting company Metsul.
Usually, this favors the formation of “flying rivers” that carry moisture from the Amazon south. But due to the prolonged drought and fires, instead of precipitation, “the wind path carries smoke to several regions of Brazil.”
“The air quality is already poor because of the drought, but the smoke makes the situation worse by bringing in soot nanoparticles,” adds the specialist.
According to INPE data, the number of fires in the Amazon since the beginning of the year has almost doubled compared to the same period in 2023.
Other regions of Brazil have been plagued by devastating wildfires in recent days, notably in the Chapada dos Veadeiros National Park, about 250 km north of Brasilia, where more than 10,000 hectares have gone up in smoke.
Another phenomenon linked to the smoke from the fires: in many regions of Brazil, the sunset has taken on orange-red hues.
“At sunset, the rays pass through nanoparticles invisible to the naked eye which give them this orange-red tone,” says Estael Sias.
According to her, the smoke is not expected to clear “without regular rainfall,” which is not expected “before October or November.”