Enhancing oceanic light availability below the photic layer

Oceans & marine

Ocean bioproductivity through photosynthesis stops beyond the photic layer as no more energy from the sun can penetrate beyond that point.

There have been some isolated speculations about a way to increase light availability at deeper levels, so as to allow more carbon sequestration in biomatter through photosynthesis. It is however very unclear how this would work. A reference to the idea can be found here: https://groups.google.com/g/CarbonDioxideRemoval/c/AXkmQwmXod0

Technological Readiness Level (TRL)

Low 1

This idea is apparently not being developed.

Technological Readiness Level (TRL)

A technology with a TRL of 1-3: TRL 1 – Basic; TRL 2 – Concept formulated; TRL 3 – Experimental proof of concept

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Scalability

Low 1

Scalability

Physically unable to scale; sub-linear/logarithmic efficiency of scalability

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Timeliness for near-future effects

Low 1

Timeliness for near-future effects

Implemented too late to make a significant difference

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Northern + Arctic potential

Unknown 0

Global potential

Unknown 0

Cost - benefit

Unknown 0

Environmental risks

Some risk 2

Like other ocean bioproductivity enhancement techniques, this idea potentially comes with significant environmental impacts. The deep sea impacts of such an intervention are potentially even more significant (Levin et al, 2023). There is moreover ample evidence that current levels of light producing are having significant effects on marine ecosystems (Maggi and Benedetti-Cecchi, 2018).

Environmental risks

More widespread and possibly regional impacts that extend beyond the immediate solution deployment location

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Community impacts

Unknown 0

Ease of reversibility

Unknown 0

Risk of termination shock

Unknown 0

Legality/governance

Challenging 2

Legality/governance

Fits within existing structures to a certain degree, but some policy changes are needed to deploy at scale

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Scientific/media attention

Low 1

This idea is apparently not being developed, and has only been mentioned a few times in online fora.

Scientific/media attention

Very low attention from individuals and/or abandoned ideas; low media attention; no commercial interest.

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References

Levin, L.A., Alfaro-Lucas, J.M., Colaço, A., Cordes, E.E., Craik, N., Danovaro, R., Hoving, H.J. et al. (2023) Deep-sea impacts of climate interventions Ocean manipulation to mitigate climate change may harm deep-sea ecosystems. Science. Vol 379, Issue 6636 pp. 978-981 https://doi.org/10.1126/science.ade7521

Maggi, E. & Benedetti-Cecchi, L. (2018). Trophic compensation stabilizes marine primary producers exposed to artificial light at night. Marine Ecology Progress Series, 606, 1-5. https://doi.org/10.3354/meps12769

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