Marine Dead Zones Set to Expand Rapidly

Rising levels of carbon dioxide could increase the volume of oxygen-depleted 'dead zones' in tropical oceans by as much as 50% before the end of the century — with dire consequences for the health of ecosystems in some of the world's most productive fishing grounds.

Oceanic oxygen levels have varied considerably throughout Earth's past. During the end of the Permian period, around 250 million years ago, catastrophic oxygen losses triggered mass extinction of terrestrial and marine life.

Read more