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Sequestration: Part 2 - In the Ocean

Recall the carbon cycle: The key to this issue is waiting long enough for the CO₂ in the atmosphere to reach equilibrium with the CO₂ in the ocean, at which point a significant quantity of CO₂ will have been "removed" from the atmosphere - the problem is time. As my daughter likes to say on our road trips "it is taking too long!" That is the case here. We can not afford to wait. However, the good news is that the ocean offers significant CO₂ storage capabilities (for long-term timelines).

There are 3 approaches to this process:

1. Fertilize the ocean
   Remember how crude oil is formed? If there were more "bugs" in the ocean (plankton) then as they grow and reproduce they will absorb CO₂ (remember this is photosynthesis)! They will die and decay but providing there are more of them and they are self replicating (whatever the outcome of plankton sex is) then there will be more carbon in the ocean and less CO₂ in the atmosphere. This is a carbon sink (more on this later). The ocean "bugs" can also grow shells, which they obtain from the dissolved minerals in the ocean and dissolved carbon dioxide. "She sells sea shells on the sea shore!" Try saying that 4 times as quickly as you can. So the shells can also capture CO₂ for long periods of time.

   Source: NETL: Siegenthaler and Sarimiento, Nature Vol. 356, 1993. The equilibrium between CO2 in the atmosphere and the ocean is dominated by the ocean capacity.

   Source: NETL Once we get CO2 into the ocean is still has a complex internal recycling that occurs.

2. Inject CO₂into the ocean to form hydrates (see here)

   Source: IBI The cleaned, compressed carbon dioxide needs to be transported to deep water if you wish to form an underwater CO2 lake.

   Source: ILI

3. Inject CO₂to the bottom of the ocean to form a CO₂ lake (underwater).

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