ocean acidification: Quick Facts

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Side-by-side diagram showing ocean acidification from the late 1800s to a projection for 2100. The left panel illustrates lower atmospheric carbon dioxide, higher seawater pH, and abundant healthy corals and shells due to more carbonate ions. The right panel shows higher carbon dioxide, lower pH, fewer carbonate ions, and fewer, smaller marine calcifiers, highlighting the negative impact on ocean life.

A scuba diver swims above a colorful coral reef in the Maldives, surrounded by schools of small orange fish and several butterflyfish among the rocks.

Infographic showing a timeline of major climate change milestones from 1896 to 2025, with key events listed on the left. Insets on the right display a graph of rising atmospheric carbon dioxide levels, diagrams of ocean acidification due to carbon dioxide, and a world map highlighting countries that have signed or ratified the Paris Agreement.

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Ocean Acidification: How Carbon Dioxide Is Hurting the Seas air pollution environmental change hydrosphere ocean ocean current wave ocean warming tide Water cycle lake Today in History—October 21: Magellan Finds a Route to the Pacific Who owns the oceans?seawater iceberg

water glass on white background. (drink; clear; clean water; liquid)

Water and its Varying Forms