: Scientists recently discovered that metallic nodules on the deep seafloor can produce oxygen through a process called electrolysis, even in total darkness. Environmental Threats (Deoxygenation)

: Most of the ocean's oxygen comes from tiny marine plants, algae, and some bacteria that photosynthesize like land plants.

Ocean oxygen levels are currently declining due to two primary human-driven factors:

: While the ocean produces roughly 50% of Earth’s oxygen, marine life also consumes about the same amount through respiration.