Final answer:
As atmospheric CO2 levels rise, CO2 in the ocean also increases, leading to decreased ocean pH, a process called ocean acidification. This increased acidity hinders the ability of sea life to produce hard exoskeletons, especially affecting corals and shellfish and can have widespread effects on marine ecosystems. Therefore the correct answer is O Increase, decrease
Step-by-step explanation:
As levels of carbon dioxide (CO2) increase in the atmosphere, the levels of carbon dioxide dissolved in the ocean will increase, causing the pH levels to decrease. This process is known as ocean acidification, which results from the absorption of atmospheric CO2 by ocean waters. This absorption leads to a chemical reaction that produces hydrogen ions (H+), thereby increasing the acidity of the oceans. As a result, the availability of calcium carbonate, a crucial component for marine organisms to build their exoskeletons and shells, is significantly reduced. This can make it difficult for sea life like coral, mollusks, and plankton to produce their hard exoskeletons.
The increase in ocean acidity can have dramatic effects on marine ecosystems and biodiversity. For example, coral reefs, which provide habitat for many marine species, are particularly vulnerable to acidification. The increased acidity can interfere with the calcification process essential for corals to build their calcium carbonate structures. This could lead to a decline in coral populations and the overall health of reef ecosystems.