The Amazon rainforest is on fire. Climate scientists fear a tipping point is near

Flames are spreading across the Amazon rainforest this summer, spewing millions of tons of carbon dioxide into the atmosphere each day. But scientists say that's not their biggest concern. They're far more worried about what the fires represent: a dramatic increase in illegal deforestation that could deprive the world of a critical buffer against climate change.

More than a soccer field's worth of Amazon forest is falling every minute, according to Brazil's National Institute for Space Research, known as INPE. Preliminary estimates from satellite data revealed that deforestation in June rose almost 90% compared with the same month last year, and by 280% in July.

The Amazon is a key component of Earth's climate system. It holds about a quarter as much carbon as the entire atmosphere and single-handedly absorbs about 5% of all the CO2 we emit each year.

But if such rapid deforestation continues, it will foil efforts to keep global temperatures in check. Scientists fear parts of the Amazon could pass a critical threshold and transform from a lush rainforest into a dry, woody grassland. And that could bring catastrophic consequences