Fires in the Amazon rainforest have captured attention worldwide in recent days. Brazilian President Jair Bolsonaro, who took office in 2019, pledged in his campaign to reduce environmental protection and increase agricultural development in the Amazon, and he appears to have followed through on that promise.
The resurgence of forest clearing in the Amazon, which had decreased more than 80% following a peak in 2004, is alarming for many reasons. Tropical forests harbor many species of plants and animals found nowhere else. They are important refuges for indigenous people, and contain enormous stores of carbon as wood and other organic matter that would otherwise contribute to the climate crisis.
Some media accounts have suggested that fires in the Amazon also threaten the atmospheric oxygen that we breathe. French President Emmanuel Macron tweeted on Aug. 22 that “the Amazon rain forest – the lungs which produces 20% of our planet’s oxygen – is on fire.”
The oft-repeated claim that the Amazon rainforest produces 20% of our planet’s oxygen is based on a misunderstanding. In fact nearly all of Earth’s breathable oxygen originated in the oceans, and there is enough of it to last for millions of years. There are many reasons to be appalled by this year’s Amazon fires, but depleting Earth’s oxygen supply is not one of them.
More at PBS