Ocean acidification

Definition

Ocean acidification refers to the process by which the ocean becomes more acidic due to the absorption of excess atmospheric carbon dioxide (CO2). This increase in acidity can disrupt marine ecosystems, affect the carbon cycle, and has implications for sea level rise, as it impacts the health of marine organisms that contribute to carbon storage and coastal protection.

5 Must Know Facts For Your Next Test

1. Since the Industrial Revolution, ocean acidity has increased by about 30%, affecting marine life and ecosystems.
2. Acidic waters can hinder the ability of calcifying organisms to form shells and skeletons, threatening biodiversity in marine habitats.
3. Ocean acidification also affects fish behavior and sensory functions, which can have cascading effects on marine food webs.
4. The phenomenon is closely linked to climate change, as both are driven by elevated levels of CO2 in the atmosphere.
5. Coastal regions, which are heavily dependent on healthy marine ecosystems for fisheries and tourism, face economic risks due to ocean acidification.

Review Questions

• How does ocean acidification impact marine ecosystems and their associated food webs?
  • Ocean acidification affects marine ecosystems by disrupting the ability of calcifying organisms to build their shells and skeletons. This decline in species like corals and shellfish can destabilize food webs since many marine animals rely on these organisms for habitat and nutrition. As these foundational species struggle to survive, it can lead to decreased biodiversity and alter the dynamics of entire ecosystems.
• In what ways do human activities contribute to both ocean acidification and climate change?
  • Human activities such as burning fossil fuels release large amounts of carbon dioxide into the atmosphere. A significant portion of this CO2 is absorbed by the oceans, leading to ocean acidification. This process not only contributes to the declining health of marine ecosystems but also exacerbates climate change by reducing the ocean's capacity to act as a carbon sink. Consequently, the interconnectedness of these issues makes addressing them simultaneously crucial for environmental health.
• Evaluate the potential economic impacts of ocean acidification on coastal communities reliant on marine resources.
  • The economic impacts of ocean acidification on coastal communities can be severe, especially for those reliant on fisheries and tourism. As shellfish populations decline due to increased acidity, local fisheries may face reduced catches, impacting livelihoods and local economies. Additionally, coral reefs that attract tourists may suffer from bleaching and reduced growth rates, leading to declines in tourism revenue. Addressing these economic challenges requires comprehensive strategies that consider both environmental conservation and community resilience.

Related terms

carbon dioxide:

A colorless gas that is naturally present in the atmosphere, it is a significant greenhouse gas released by human activities, leading to climate change and ocean acidification.

calcifying organisms:

Marine organisms, such as corals and shellfish, that build their shells or skeletons from calcium carbonate; these organisms are particularly vulnerable to the effects of ocean acidification.

carbon cycle: The natural process by which carbon is exchanged among the atmosphere, oceans, soil, and living organisms; human activities have disrupted this cycle, contributing to increased ocean acidification.