CO2 Absorption

Definition

CO2 absorption refers to the process by which carbon dioxide is taken up by various systems, particularly by oceans, where it interacts with water to form carbonic acid. This process is crucial for regulating atmospheric CO2 levels and maintaining the balance of carbon in the environment. It plays a significant role in ocean carbon dynamics, affecting both the chemistry and biological processes within marine ecosystems while contributing to ocean acidification.

5 Must Know Facts For Your Next Test

1. About 30% of human-generated CO2 emissions are absorbed by oceans, helping to mitigate climate change effects.
2. As CO2 is absorbed, it reacts with seawater to form carbonic acid, which can lead to a decrease in pH levels and thus contribute to ocean acidification.
3. Increased CO2 absorption can negatively impact marine organisms, particularly calcifying species like corals and shellfish, which struggle to maintain their calcium carbonate structures in more acidic waters.
4. CO2 absorption affects marine food webs, as changes in pH can alter nutrient availability and disrupt the growth of phytoplankton, which are foundational to ocean ecosystems.
5. The efficiency of CO2 absorption varies with temperature, salinity, and biological activity, indicating that warmer oceans may absorb less CO2 in the future.

Review Questions

• How does CO2 absorption contribute to ocean acidification and what are its implications for marine ecosystems?
  • CO2 absorption leads to ocean acidification as absorbed CO2 forms carbonic acid, lowering the pH of seawater. This change in acidity has dire implications for marine ecosystems, especially for calcifying organisms such as corals and shellfish that rely on stable pH levels to build their calcium carbonate structures. As these species struggle to survive in more acidic waters, the overall health of marine ecosystems is jeopardized, impacting biodiversity and food webs.
• Discuss the role of dissolved inorganic carbon (DIC) in the context of CO2 absorption and its significance for marine biogeochemistry.
  • Dissolved inorganic carbon (DIC) is formed when CO2 is absorbed by ocean water, playing a pivotal role in marine biogeochemical cycles. DIC exists primarily as bicarbonate and carbonate ions, which are crucial for various biological processes such as photosynthesis and calcification. The balance of DIC not only affects nutrient availability for marine organisms but also influences the ocean's ability to sequester carbon from the atmosphere, thereby playing a vital part in regulating global climate.
• Evaluate how increasing atmospheric CO2 concentrations may affect future trends in CO2 absorption by oceans and the potential consequences for global climate change.
  • As atmospheric CO2 concentrations continue to rise due to human activities, the oceans initially absorb more CO2. However, this increased absorption may not be sustainable as warmer temperatures reduce solubility and alter biological productivity. The long-term consequences could include decreased oceanic capacity to act as a carbon sink, exacerbating climate change impacts. Additionally, ongoing ocean acidification will threaten marine life and disrupt ecosystems that are essential for carbon cycling, potentially creating feedback loops that further accelerate climate change.

Related terms

Ocean Acidification: The decrease in pH levels of the ocean caused by the absorption of excess CO2 from the atmosphere, leading to harmful effects on marine life.

Carbon Cycle: The series of processes through which carbon compounds are interconverted in the environment, including absorption by oceans, vegetation, and soils.

Dissolved Inorganic Carbon (DIC): The form of carbon present in the ocean, primarily as bicarbonate and carbonate ions, which results from CO2 absorption and is essential for marine biogeochemical processes.