The "20% of the world's oxygen" claim is unfounded. https://www.forbes.com/sites/rachelsandler/2019/08/23/as-the-amazon-fires-spread-so-did-this-unfounded-stat

The "20% of the world's oxygen" claim is unfounded. https://www.forbes.com/sites/rachelsandler/2019/08/23/as-the-amazon-fires-spread-so-did-this-unfounded-statistic/#1fe26c7a1ea9 https://www.forbes.com/sites/rachelsandler/2019/08/23/as-the... As the professor states in his tweets, there are legitimate reasons to avoid deforestation ("for climate, for biodiversity, for indigenous communities"). Oxygen supply is not one of them.