Ocean acidification

Definition

Ocean acidification refers to the process by which the ocean becomes more acidic due to increased absorption of carbon dioxide (CO2) from the atmosphere. As CO2 levels rise, a significant portion is absorbed by seawater, leading to chemical reactions that decrease the pH of the ocean. This change in acidity can disrupt marine ecosystems, affecting organisms that rely on calcium carbonate for their shells and skeletons, and has broader implications for climate variability and extreme weather events.

5 Must Know Facts For Your Next Test

1. The ocean has absorbed about 30% of the carbon dioxide emitted into the atmosphere since the industrial revolution, significantly lowering its pH levels.
2. Ocean acidification can harm marine life, particularly shellfish and coral reefs, which rely on calcium carbonate to build their structures.
3. As ocean acidity increases, it affects not only individual species but also entire ecosystems, leading to shifts in biodiversity and food web dynamics.
4. This process is closely linked with climate change, as rising temperatures and changing currents can exacerbate the effects of ocean acidification.
5. Ocean acidification can also impact human communities that depend on fishing and aquaculture, leading to economic challenges in coastal regions.

Review Questions

• How does ocean acidification impact marine life and ecosystems?
  • Ocean acidification impacts marine life by reducing the availability of calcium carbonate, which is essential for organisms like coral reefs and shellfish to build their shells and skeletons. As the acidity increases, these organisms may struggle to survive or reproduce, leading to declines in their populations. This disruption can cause cascading effects throughout marine ecosystems, altering food webs and biodiversity.
• Discuss the relationship between ocean acidification and climate variability.
  • Ocean acidification is intricately linked to climate variability as both processes are driven by increased carbon dioxide emissions. The rise in CO2 levels not only contributes to warming temperatures but also leads to greater absorption of CO2 by the oceans, resulting in acidification. Changes in ocean chemistry can further influence climate patterns by affecting ocean currents and heat distribution, demonstrating how interconnected these phenomena are.
• Evaluate the potential socio-economic implications of ocean acidification for coastal communities.
  • The socio-economic implications of ocean acidification for coastal communities can be profound, particularly for those reliant on fisheries and aquaculture. As shellfish populations decline due to reduced calcium carbonate availability, fishing yields could decrease, leading to economic losses and food insecurity for communities dependent on these resources. Furthermore, disruptions in marine ecosystems could impact tourism and recreational activities, compounding the challenges faced by these regions in adapting to environmental changes.

Related terms

Carbon dioxide: A colorless gas produced by burning fossil fuels and through natural processes, which is a major contributor to greenhouse gas emissions and ocean acidification.

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

Calcium carbonate: A chemical compound (CaCO3) used by many marine organisms to form shells and skeletons, which can be negatively affected by decreasing ocean pH.