Ocean acidification is a consequence of the Industrial Age’s emissions of CO₂, which gradually dissolves in seas, forming carbonic acid. Sea life performs the net carbon sequestration for the planet via calcifying organisms that build shells or skeletons from the calcium carbonate ions in seawater. When these organisms die, they sink, taking their carbonate parts to the seafloor, where limestone is continually forming. That sequesters carbon from air and sea sources until the limestone is subducted into deep volcanic systems.

Unfortunately, human CO₂ emissions have become 1500 times what the sea-life cycle can handle each year. As a result, oceans have become less alkaline and may, before 2050, reach pH values below which sea life can no longer extract carbonate ions. They thus die, killing both their carbon sequestration and food chains serving ~20% of all human food protein on the planet. Only advanced, clean sources of high-temperature heat can prevent this occurrence before 2050, and those sources are only available in sufficient capacity via advanced nuclear systems.