NGS Picture Id:1445199 - The Years Project

NGS Picture Id:1445199

A few hundred yards from the preceding scene, CO₂ bubbling from seafloor vents acidifies the water to levels that might one day prevail all over the oceans. Dull mats of algae replace the colorful diversity—”fair warning,” says biologist Jason Hall-Spencer. Photo: David Liittschwager, National Geographic Creative.

Carbon dioxide bubbles rising from the seafloor