The Amazon forest, which produces about 20% of earth's oxygen, is often referred to as "the planet's lungs."

Currently, the Amazon is a "sink" for carbon dioxide (CO2), the gas that is emitted mainly from burning fossil fuels, such as coal, oil and natural gas, according to WWF. Under natural conditions, plants remove CO2 from the atmosphere and absorb it for photosynthesis, yielding carbon, which allows plants to grow, and releasing oxygen back into the air.

Here's what we know about the fires in the Amazon rainforest