Ocean acidification

Definition

Ocean acidification refers to the process by which the ocean becomes more acidic due to increased levels of carbon dioxide (CO2) absorbed from the atmosphere. This phenomenon is closely tied to climate change, as rising global temperatures lead to higher CO2 emissions, which in turn dissolve in seawater and lower the pH, impacting marine ecosystems and species.

5 Must Know Facts For Your Next Test

1. The ocean absorbs about 30% of the carbon dioxide emitted into the atmosphere, leading to a decrease in pH levels over time.
2. As ocean acidity increases, it can have detrimental effects on calcifying organisms like corals and shellfish, which struggle to form their shells and skeletons.
3. Ocean acidification can disrupt food webs by affecting the survival and growth of key marine species that serve as food for larger animals.
4. Areas like the Pacific Northwest are particularly vulnerable to ocean acidification due to upwelling of CO2-rich waters and their dependence on shellfish fisheries.
5. Mitigating ocean acidification requires global efforts to reduce CO2 emissions and protect marine habitats that can help buffer changes in acidity.

Review Questions

• How does ocean acidification impact marine life, particularly organisms that rely on calcium carbonate for their shells?
  • Ocean acidification significantly impacts marine life by lowering the availability of carbonate ions needed for organisms like corals, mollusks, and some plankton to build their calcium carbonate shells and skeletons. As the pH decreases, these organisms find it harder to calcify, which can lead to weaker structures and increased mortality rates. This disruption not only threatens individual species but also affects entire ecosystems that rely on these organisms for habitat and food.
• What role does carbon dioxide play in both ocean acidification and climate change, and how are these two processes interconnected?
  • Carbon dioxide plays a crucial role in both ocean acidification and climate change as it is a significant greenhouse gas emitted from human activities. When CO2 is released into the atmosphere, a portion is absorbed by the ocean, leading to chemical reactions that decrease pH levels and increase acidity. This connection shows how our carbon emissions not only contribute to global warming by trapping heat but also alter ocean chemistry, ultimately affecting marine biodiversity and fisheries.
• Evaluate the potential long-term consequences of ocean acidification on global marine ecosystems and human economies dependent on them.
  • The long-term consequences of ocean acidification could be profound for global marine ecosystems and economies that depend on them. If current trends continue, many marine species may face extinction or significant population declines, leading to altered food webs and ecosystem services. Human communities reliant on fisheries for income and sustenance may experience economic hardships as fish populations decline. Additionally, industries such as tourism, particularly in regions with coral reefs, may suffer as these vital habitats degrade. Overall, failure to address ocean acidification could result in irreversible damage to both marine life and human livelihoods.

Related terms

carbon dioxide: A colorless, odorless gas produced by burning fossil fuels, respiration, and other processes; a major greenhouse gas contributing to climate change.

pH scale: A scale used to specify how acidic or basic a water-based solution is, ranging from 0 (very acidic) to 14 (very basic), with 7 being neutral.

marine ecosystems: Complex communities of living organisms and their physical environment in the ocean, including coral reefs, mangroves, and open water habitats.