Keys to understand the role of the Amazon in climate change

The fires in the Brazilian Amazon sparked an international outcry for the conservation of the world’s largest rainforest. Now, by virtue of the role that the largest “lung of the planet” plays in regulating the global climate, we will try to answer the following questions.

Is the global oxygen supply at risk? No. It is said that the Amazon produces 20% of the world’s oxygen, but climatologists say that the figure is wrong and in any case the supply of oxygen is not in danger. That’s because rainforests, including the Amazon, absorb about the same amount of oxygen they produce. Plants produce oxygen through photosynthesis, but absorb it to grow, just like animals and microbes.

That doesn’t mean fires aren’t a problem for the planet. The Amazon is crucial in absorbing carbon dioxide, a gas produced by the burning of fossil fuels such as oil and coal.

Is the Amazon really the “lung of the world”? It’s usually called that way, but it’s perhaps not the most accurate analogy.

Climatologist Carlos Nobre, of the University of São Paulo, says it is more accurate to present the function of the Amazon as a device for draining carbon dioxide, a gas that traps heat from the atmosphere. Currently, the world emits 40 billion tons of _CO2 annually. The Amazon absorbs 2 billion tons of _CO2 per year (5% of annual emissions), hence its vital role in preventing climate change.

What do fires mean for the global climate? Not only does the flora that absorb carbon disappear, but also that the flames emit millions of tons of it. Nobre says we are approaching a “tipping point” that would transform the dense jungle into a tropical savannah.

The rainforest recycles its own water to produce some of the region’s rainfall; therefore, deforestation reduces rainfall and prolongs the dry season. Nobre estimates that if 20 to 25% of the forest is destroyed, the dry season will last long enough to transform it into savannah. “Unfortunately, we already see signs of the transformation of the Amazon into a savannah. It’s already happening,” he said.

Fire

What is the cause of the fire? Today’s fires are natural. They are caused by man, mainly land usurpers who illegally light them to clear the forest for cattle raising and crops.

Deforestation of the Amazon is a long and slow process. People clear the land by cutting down vegetation during the rainy season, letting trees dry and burning them during drying. Clearing dense afforestation for agriculture usually requires several years of slash and burn. “When I talk about deforestation in the 21st century, I don’t mean a family entering the forest with a chainsaw, but tractors uprooting trees,” said NASA researcher Doug Morton.

He said that three months ago researchers saw, through satellite images, stacked logs that are then lit.

“What has changed is the political argumentation,” Nobre said. President Jair Bolsonaro took power and autonomy away from the jungle protection agencies, which he says prevent the granting of licenses to take advantage of the land. He calls them the “fine industry.” “The fires are going up because people believe that the police will not punish them,” he said.

Source: La Voz