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Ocean Acidification

Oceanography

The ongoing decrease in the pH of Earth's ocean as it absorbs carbon dioxide from human emissions; between 1950 and 2020 the average surface pH fell from approximately 8.15 to 8.05. The absorbed gas forms carbonic acid whose free hydrogen ions lower the pH, and marine calcifying organisms such as mollusks and corals are especially vulnerable because they rely on calcium carbonate to build shells and skeletons. The seawater remains alkaline; the change is a shift toward acidity, not past it. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/

Facts
Timescale
Ongoing; average surface pH fell from about 8.15 to 8.05 between 1950 and 2020 1
Driving Force
The ocean's absorption of atmospheric carbon dioxide, which reacts with seawater to form carbonic acid and lower ocean pH. 1
Resulting Feature
Reduces the concentration of carbonate ions that marine organisms such as corals, mollusks and some plankton need to build calcium carbonate shells and skeletons; below the saturation horizon, calcium carbonate dissolves rather than accumulates. 1
Significance
Ocean acidification threatens coral reefs and shellfish fisheries and is often described as climate change's companion consequence, since both stem from rising atmospheric carbon dioxide. 1
Driving Force
Driving Force (category)
Hydrological / Water 1
Connections

Associated With

The increased carbon dioxide has reduced the ocean's pH and is altering marine chemistry.

Source Carbon Cycle (Wikipedia)

Past ocean acidification episodes had long-lasting effects on the global carbon cycle and climate.

Source Ocean Acidification (Wikipedia)

In Discipline

Source Ocean Acidification (Wikipedia)
In the Other Atlases

Same As

Also in Nature Atlas: the same subject.

Sources
1. Ocean Acidification (Wikipedia)
Wikimedia FoundationLead section
Quote, Lead section
Ocean acidification is the ongoing decrease in the pH of the Earth's ocean. Between 1950 and 2020, the average pH of the ocean surface fell from approximately 8.15 to 8.05.
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