A Solution to Excess CO2? New Study Proposes Fertilizing the Ocean

Fertilizing the Ocean to Store Carbon Dioxide

Seeding the oceans with nano-scale fertilizers could create a much-needed, substantial carbon sink. Credit: Illustration by Stephanie King | Pacific Northwest National Laboratory

Iron-based fertilizer in the form of nanoparticles has the potential to store excess carbon dioxide in the ocean.

An international team of researchers led by Michael Hochella of the Pacific Northwest National Laboratory suggests that utilizing tiny organisms could be a solution to addressing the pressing need to remove excess carbon dioxide from the Earth’s environment.

The team conducted an analysis, published in the journal Nature Nanotechnology, on the possibility of seeding the oceans with iron-rich engineered fertilizer particles near ocean plankton, crucial microscopic plants in the ocean ecosystem, to boost the growth and carbon dioxide uptake of phytoplankton.

“The idea is to augment existing processes,” said Hochella, a Laboratory fellow at Pacific Northwest National Laboratory. “Humans have fertilized the land to grow crops for centuries. We can learn to fertilize the oceans responsibly.”

Michael Hochella

Michael Hochella is an internationally recognized environmental geochemist. Credit: Virginia Tech Photographic Services

In nature, nutrients from the land reach oceans through rivers and blowing dust to fertilize plankton. The research team proposes moving this natural process one step further to help remove excess CO2 through the ocean. They studied evidence that suggests adding specific combinations of carefully engineered materials could effectively fertilize the oceans, encouraging phytoplankton to act as a carbon sink. The organisms would take up carbon in large quantities. Then, as they die, they would sink deep into the ocean, taking the excess carbon with them. Scientists say this proposed fertilization would simply speed up a natural process that already safely sequesters carbon in a form that could remove it from the atmosphere for thousands of years.

“At this point, time is of the essence,” said Hochella. “To combat rising temperatures, we must decrease CO2 levels on a global scale. Examining all our options, including using the oceans as a CO2 sink, gives us the best chance of cooling the planet.”

Pulling insights from the literature

In their analysis, the researchers argue that engineered nanoparticles offer several attractive attributes. They could be highly controlled and specifically tuned for different ocean environments. Surface coatings could help the particles attach to plankton. Some particles also have light-absorbing properties, allowing plankton to consume and use more CO2. The general approach could also be tuned to meet the needs of specific ocean environments. For example, one region might benefit most from iron-based particles, while silicon-based particles may be most effective elsewhere, they say.

The researchers’ analysis of 123 published studies showed that numerous non-toxic metal-oxygen materials could safely enhance plankton growth. The stability, Earth abundance, and ease of creation of these materials make them viable options as plankton fertilizers, they argue.

The team also analyzed the cost of creating and distributing different particles. While the process would be substantially more expensive than adding non-engineered materials, it would also be significantly more effective.

Reference: “Potential use of engineered nanoparticles in ocean fertilization for large-scale atmospheric carbon dioxide removal” by Peyman Babakhani, Tanapon Phenrat, Mohammed Baalousha, Kullapa Soratana, Caroline L. Peacock, Benjamin S. Twining and Michael F. Hochella Jr., 28 November 2022, Nature Nanotechnology.
DOI: 10.1038/s41565-022-01226-w

In addition to Hochella, the team included researchers from England, Thailand, and several US-based research institutions. The study was funded by the European Research Council under the European Union’s Horizon 2020 research and innovation program.

22 Comments on "A Solution to Excess CO2? New Study Proposes Fertilizing the Ocean"

  1. This is a dangerous proposal. While the currently accepted paradigm is that anthropogenic CO2 is responsible for the warming that has been occurring since at least the start of the Industrial Revolution, there is considerable evidence to suggest that CO2 plays a minor role, at best. The problem is that most scientists are turning a blind eye to the contradictory evidence, and the Media is actively supporting the paradigm. They accept that the science is settled.

    It is hubris to assume that we understand climatology well enough to purposely attempt to alter the system in a manner that is thought to be necessary. Changing the CO2 concentration will ripple through ecosystems and could trigger changes that we would be powerless to do anything about and be forced to ride it out until a new equilibrium is established. And, we may not like the new equilibrium!

    One of the most obvious possibilities is that the expected reduction in temperature may not happen, and the fertilization will result in a population explosion of plankton, which when it crashes, will result in anoxia in the ocean and a collapse of the marine food chain.

    • I agree it’s carbon monoxide that’s the problem. Carbon Monoxide is a poison to our bodies skin & lungs.

    • Would love to see the “considerable evidence” that CO2 plays a “minor” role. Please give us the links to the peer reviewed studies that agree with your ridiculous statement. What? You can’t? Because your claims are based on fossil fuel funded websites with articles written by non-scientists? What a surprise.

    • Clyde, you are correct to flag the dangers in a wider context. Narrow scientific studies should be done and are easier to make progress in, but all too often the system wide issues are ignored only to precipitate more damaging affects in the environment. Take for example what keeps the toxic bio-organisms (causing paralytic shellfish poison, ciguatera, etc.) from taking advantage of the CO2 rich environment?

  2. So now they are proposing to screw the oceans up….its simple really, ban coal usage altogether, ban civilian aviation for ten years, ban fossil fuels for transport. I am not a tree hugger, but common sense dictates this, we have not had a large war since 1939 to reduce the male breeding stock so overpopulation has caused the problems we now face.

    • Why don’t you just offer to put a bullet through 2 billion people’s heads? It would be a lot more humane than the slow death you are proposing.

      • No I am not proposing slow deaths, they are already facing that from a poisoned planet, and it will not be 2 billion but more like the current 8 billion facing a slow death.

    • Male breeding stock

  3. Genius solution as solely the ocean itself is the only tool large enough to adequately do the job. Nanoparticles have such as bad zen about them…. maybe just feed it fertilizers so the plankton will grow better and healthier. Surely there are natural ways to boost the phyto-planktons health and vitality

  4. Think twice, proposal is dangerous. There are scientific observations in shallow seas, like Baltic Sea, how excess fertilizing causes a major problem. Sea water gets contaminated by heavy growth of algea, that generate poisonous substances killing the fish, damaging the food chain, and swimming becomes impossible due to skin reactions.

    • One doesn’t have to go to the Baltic Sea. Lake Erie has a significant problem with toxic algae resulting from fertilizer runoff, principally from corn and soy farms. Causing algae blooms accidentally, in the process of growing food, at least has some off-setting benefits. Without an absolute guarantee, which is not currently possible, that promoting the growth of marine plankton will result in stabilizing Earth’s temperature, we run the risk of disrupting the food chain in the hopes of stopping warming. This is a big risk to take when there isn’t a guarantee it will accomplish the intended goal.

  5. This also could cause a new ice age by cooling the planet too much!

  6. Iron fertilization has been tried before. It doesn’t work because it increases all primary productivity of algae that will be quickly recycled with no net change. Only those algae that synthesize carbonates would be helpful (coccolith calcite). Diatoms are amorphous silica which contains no carbon. But massive amounts of nano-sized hydrous iron oxides would have to be produced and used…and the process repeated. That alone would add CO2. Probably much more than was sequestered by coccoliths. On balance a bad idea.

  7. Hamish McGonigle | January 21, 2023 at 2:39 pm | Reply

    what about stopping coal mining and burning

    • You could just stop breathing instead of causing the freezing deaths of countless Ukrainians and others dependent on coal for heat and electricity. I’m sorry, but THEORIES mean NOTHING in the face of certain death of freezing to death. But then that touches the REAL problem is not human activity, but the fact there are just too darn many humans on the planet, with associated animal herds to feed, etc. The planet population should ideally not exceed 2 Billion people and we are pushing 8 billion.

      Two things feed this. One is ancient religious doctrine that says “Be fruitful and multiply” and along now with a movement to limit or eliminate abortion, that’s only making the problem that much worse and for no reason other than superstitious belief in the occult. The other is NO ONE and I mean NO ONE is talking about doing something about human overpopulation. Telling people they CANNOT have any children or limiting how many they can have is INCREDIBLY UNPOPULAR. The idea of shutting down coal at least sounds good on the surface to SJW types who cannot think outside the box. But in a society whose economic system demands constant “growth” it’s not easily defeated.

      Thus, an apparent solution is NOT TO TELL THEM what you’re doing. I think you’ll soon discover that the pandemic had oddly sterilizing or fertility reduction effects heretofore not yet noticed in the long run. They can just blame it on the virus. No human made that decision. Those required vaccines have nothing to do with it, of course. Puberty blockers also cause 100% sterilization (coincidence they’ve increased in use over 10x in the past ten years?) I think you’ll find a lot of new drugs turn out to have sterilization side effects. It’s the only way to pass the blame when we need to reduce the population and we know the public will not cooperate (although there is a sudden recent movement to wipe humans from the face of the earth by voluntarily not propagating). Coincidence again?

  8. It’s carbon monoxide. Carbon Monoxide poisons our skin – hair & lungs.

  9. @ken towe

    Nailed it to a degree. Diatoms still contain organic carbon, albeit probably less than coccoliths on a per cell level, but that may be offset by higher densities potentially achievable with diatoms. Main problem like you said, is getting the organic carbon to settle on the ocean floor without being recycled into the food web, and released as CO2 again.

  10. Actually if you read the paper. Pretty much all of your objections are explained.
    It’s not a CO2 generating process. They account for the CO2 costs of producing, and transporting the engineered particles.

    Also diatoms contain plenty of organic carbon. The Silicate shell helps with sinking and is a hindrance to grazers, which assists in settling.

    Read the paper!!

  11. Often I am puzzled. I remember this whole issue being proposed and tested 50 years ago. Am I just too old? I suspect much that was done before Google has vanished…who wants to look in a book?
    I frequently see questions that had pre-internet answers…even I can’t Google them, and I won’t go to the library either. It has probably been cleaned of all the “olde” stuff.”
    ps: I tried to get Google to digitize a copy of Popular Science which was not in their index…Nobody was interested.

  12. How about all these geniuses just let the plants have the CO2 like God intended? More CO2 more plants, win win win!
    CO2 is actually greening the earth as shown by NASA satalittes and feeding the starving. All with less water during a drought cycle.
    I thought deforestation was bad? Warmer climate with more CO2 fixes that.
    And geniuses want to stop that. As soon as I hear the word “expert” I run.

  13. How about all these geniuses just let the plants have the CO2 like God intended? More CO2 more plants, win win win!
    CO2 is actually greening the earth as shown by NASA satalittes and feeding the starving. All with less water during a drought cycle.
    I thought deforestation was bad? Warmer climate with more CO2 fixes that.
    And geniuses want to stop that. As soon as I hear the word “expert” I run.

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