Ocean Acidification Crosses Planetary Boundary, Threatens Global Marine Ecosystems

A recent study reveals that ocean acidification crossed a critical planetary boundary five years ago, posing an existential threat to marine ecosystems and human societies.

What is Ocean Acidification?

• Ocean acidification occurs when oceans absorb excess carbon dioxide (CO₂) from the atmosphere, lowering pH levels and making seawater more acidic.
• This reduces calcium carbonate levels, which marine organisms like corals, mollusks, and sea butterflies need to build shells and skeletons.
• The boundary for safe ocean acidity is crossed when calcium carbonate availability drops below 20% of pre-industrial levels. The current global average is now at 17%.