Oceans capture carbon through both biological and chemical processes.
Understanding Ocean Carbon Capture
The ocean plays a critical role in regulating the Earth's climate by absorbing a significant portion of the carbon dioxide (CO2) released into the atmosphere. This capture occurs through two primary mechanisms: biological processes and simple chemistry.
Biological Carbon Capture
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Photosynthesis by Phytoplankton: Like plants on land, phytoplankton, microscopic plant-like organisms, utilize photosynthesis to convert CO2 and sunlight into energy and biomass. This process effectively removes carbon from the atmosphere and incorporates it into the marine food web.
- Phytoplankton are responsible for a significant portion of the world's oxygen production and carbon capture.
- When phytoplankton die, their carbon-containing remains can sink to the ocean floor, effectively sequestering carbon for long periods.
Chemical Carbon Capture
- Direct Absorption of CO2: Carbon dioxide readily dissolves in seawater, a simple chemical process that directly removes CO2 from the atmosphere. The amount of CO2 that can be dissolved depends on factors like water temperature and salinity.
- Colder water can dissolve more CO2 than warmer water.
- This process helps to regulate the pH of the ocean, although increasing CO2 levels are leading to ocean acidification.
Here's a summary in a table:
| Process | Mechanism | Organisms Involved | Key Factors |
|---|---|---|---|
| Biological Capture | Photosynthesis | Phytoplankton | Sunlight, nutrients |
| Chemical Capture | Direct dissolution of CO2 in seawater | N/A | Water temperature, salinity, CO2 concentration |
The ocean's ability to capture carbon is vital for mitigating climate change. As mentioned in the provided resource, "The ocean takes up carbon dioxide through photosynthesis by plant-like organisms (phytoplankton), as well as by simple chemistry: carbon dioxide dissolves in water" (01-Jul-2008). These natural processes help regulate atmospheric CO2 levels, but they are increasingly impacted by human activities such as increased CO2 emissions and ocean warming.
