Fires are not normal in rainforest ecosystems; these humid, closed-canopy forests normally have little flammable material. Globally, only around 4% of all forest fires have natural causes such as lightning or extreme weather events. In all other cases, humans are responsible, either by deliberately clearing the land or by carelessness.

Fires in tropical rainforests are linked to deforestation, with fire used to both clear and maintain the land to produce products such as beef, soy and palm oil as well as paper and pulp. Farmers clear primary forest by felling the vegetation and leaving it to dry, and then using fire to prepare the area for agriculture – this alters the soil properties and makes the land more fertile. Fires are also used to clear areas that have previously been cleared; cattle ranchers, for example, might use this technique to eradicate weeds from their pastures. These fires can escape their intended boundaries, burning into the surrounding forests.

In Brazil, many of the fires take place on land in both the Amazon and neighbouring Cerrado region, where commodities destined for large companies are produced. The Cerrado is a tropical savanna; a highly biodiverse region which is home to an estimated 5% of the world’s animals and plants. 

Brazil is the largest exporter of both beef and soybeans in the world, with China providing the largest market for soy. For example, China alone imports 48% of soy produced in the Northern Cerrado region of Matopiba and the EU is the second-largest importer from this region, accounting for 17%. The situation is less extreme with beef, where 80% of production is consumed domestically, although the country still shipped around US$7.5 billion of beef in 2019. 

In Brazil, soy traders Bunge and Cargill together had more fires in their vicinities than all the other major soy traders combined. Among slaughterhouses, JBS, Marfrig and Minerva accounted for 60% of fires in the potential buying zones of the top 10 companies. 

In Indonesia, the world’s largest palm oil producer, 1.6 million hectares of land was burned in 2019. Almost 15,000 fire alerts were raised in the concession areas of 10 palm oil companies in 2019.

Putting out fires is not an effective way to stop deliberate fires linked to deforestation; the root causes of deforestation itself need to be tackled. Governments, both domestic and international, play a role in the extent of forest fires each year through the policies and incentives they design. For companies, there are real reputational risks of their supply chains being linked to deforestation, and a failure to address these could result in difficulties accessing markets and finance as governments and investors wise up to the risks. 

Policy and company decisions can reduce the chances of forest fires by putting downwards pressure on products linked to deforestation. In 2019, Nestle stopped sourcing Brazilian soy from Cargill, while both fashion brand H&M and shoemakers VF Corp announced they would no longer source Brazilian leather. In 2020, institutional investors which manage a combined total of US$3.7 trillion in assets have called on the Brazilian government to halt deforestation and rein in deregulation of environmental protection policies.