National Laboratory pans ocean carbon sequestration scheme

An algal bloom. The relative importance of lan...

An algal bloom. The relative importance of land- and sea-based photosynthesis may fluctuate on a 100,000-year timescale. (Photo credit: Wikipedia)

Questions rise about seeding for ocean C02 sequestration – Argonne National Laboratory

LEMONT, Ill – A new study on the feeding habits of ocean microbes calls into question the potential use of algal blooms to trap carbon dioxide and offset rising global levels.

These blooms contain iron-eating microscopic phytoplankton that absorb C02 from the air through the process of photosynthesis and provide nutrients for marine life. But one type of phytoplankton, a diatom, is using more iron that it needs for photosynthesis and storing the extra in its silica skeletons and shells, according to an X-ray analysis of phytoplankton conducted at the U.S. Department of Energy’s Argonne National Laboratory. This reduces the amount of iron left over to support the carbon-eating plankton.

“Just like someone walking through a buffet line who takes the last two pieces of cake, even though they know they’ll only eat one, they’re hogging the food,” said Ellery Ingall, a professor at the Georgia Institute of Technology and co-lead author on this result.  “Everyone else in line gets nothing; the person’s decision affects these other people.”

Because of this iron-hogging behavior, the process of adding iron to surface water – called iron fertilization or iron seeding – may have only a short-lived environmental benefit. And, the process may actually reduce over the long-term how much C02 the ocean can trap.

Rather than feed the growth of extra plankton, triggering algal blooms, the iron fertilization may instead stimulate the gluttonous diatoms to take up even more iron to build larger shells. When the shells get large enough, they sink to the ocean floor, sequestering the iron and starving off the diatom’s plankton peers.

Over time, this reduction in the amount of iron in surface waters could trigger the growth of microbial populations that require less iron for nutrients, reducing the amount of phytoplankton blooms available to take in C02 and to feed marine life.

While scientists have known for a long time that phytoplankton use iron to fuel the process of photosynthesis, there are gaps in their understanding of how this iron cycling process works. Those gaps led scientists to miss how large an amount of iron was getting trapped in those sinking skeletons and removed permanently from the food chain. X-ray studies at the Advanced Photon Source at Argonne gave scientists a way to measure the ratio of iron and silica in the plankton and surface water.

“Being able to use X-rays and see the element content of individual microscopic phytoplankton has completely altered our perspective on how these organisms use iron and how that could affect C02 levels,” Ingall said.

In the paper “Role of biogenic silica in the removal of iron from the Antarctic seas” published June 10 in the journal Nature Communications, scientists conservatively estimate that 2.5 milligrams of iron annually is removed from every square meter of surface water in the Ross Sea and sequestered in silica skeletons on the ocean floor. This is roughly equivalent to the total amount of iron deposited annually into the Ross Sea surface through snow melt, dust and upwelling of seawater.

The same process may be occurring in the Southern Ocean and having a greater impact there, because this region dictates the nutrient mix for the rest of the world’s oceans through migratory current patterns.

More study is needed to know just how much iron is used to make the silica skeletons and how much gets trapped on the ocean floor, the researchers said.

“This gap in our knowledge, combined with renewed interest in iron fertilization as an approach to the current climate crisis, makes it crucial that we have an improved understanding of iron cycling in marine systems,” Ingall said.

Measurements of iron and silicon content in silica from living phytoplankton collected in the coastal seas of West Antarctica was derived through X-ray analysis on beamlines 2-ID-D and 2-ID-E at the Advanced Photon Source using microscopy and fluorescence techniques. High-resolution imaging, chemical identification and the ability to focus X-rays on an ultra small area of about 200 by 200 nanometers were key to this analysis. For comparison, it would take 500 samples of this size to fit across the width of a single human hair.

The work was supported by the National Science Foundation and the Swedish Antarctic Research Programme. The U.S. Department of Energy’s Office of Basic Energy Sciences supported use of the APS.

The research was conducted by Ingall, Julia Diaz, Amelia Longo and Michelle Oakes from the Georgia Institute of Technology; Lydia Finney, Stefan Vogt and Barry Lai from the Advanced Photon Source; Patricia Yager from the University of Georgia; Benjamin Twining from the Bigelow Laboratory for Ocean Sciences; and Jay Brandes from the Woods Hole Oceanographic Institution.

The Goergia Institute of Technology news release can be viewed on its website.

The Advanced Photon Source at Argonne National Laboratory is one of five national synchrotron radiation light sources supported by the U.S. Department of Energy’s Office of Science to carry out applied and basic research to understand, predict, and ultimately control matter and energy at the electronic, atomic, and molecular levels, provide the foundations for new energy technologies, and support DOE missions in energy, environment, and national security. To learn more about the Office of Science X-ray user facilities, visit the Office of Science website.

Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation’s first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America’s scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science.

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Algal blooms in the Baltic Sea lead to an anoxic sea bottom.
If you intent to kill off fish, then it’s a very effective method.

Mike jarosz

This gap in our knowledge, combined with renewed interest in iron fertilization as an approach to the current climate crisis, makes it crucial that we have an improved understanding of iron cycling in marine systems,” Ingall said.
What climate crisis?

Anthony Scalzi

If the bigger shells sink quicker, wouldn’t that be good for sequestering carbon (in the form of carbonate shells)?


The Law of Unintended Consequences is waiting for the first large scale geoengineering idiots.
(I know we are currently ‘geoengineering’ but why deliberately go out there to create a strong impact by trying novel techniques on a large scale?)

What’s new about this? I believe using iron to promote CO2 eating algal blooms several times. I also seem to recall that the ideas were discredited each time.

Rhoda R

Hey Bob, it didn’t work the last time, but that’s ok, it’s GOT to work this time1

Jack Simmons

Obviously we have to get the iron hogging phytoplankton to knock it off.
Mayor Bloomberg is pretty good at telling people what they can eat and drink. Maybe after he retires as mayor, he can start a diet program with the phytoplankton.
This could be a huge genetic engineering project with a cast of thousands and a budget of billions to modify the genetic code of the iron eating plankton to push away from the buffet line when full. What dept should it be under? My vote: Department of Education; they are experts at educating people,why not plankton?
Why don’t we all just realize there is no crisis with CO2 and let it roll?
No, that’s way too crazy.


The God complex.

This video from NASA about comet Ison says Earth may be sprayed from both sides at the same time with a large amount of dust. If they are right and who ever gets these things right? Then this dust will cause similar types of effects to volcanic dust. If they are wrong then the sise of the objects coming in could mean we have a whole lot of Russian meteor type events happening all over the planet. If the iron content is sufficient or other fertilisation occurs we could get either rapid plankton growth (The biblical seas turn red turn type event). These photsynthesis based blooms are endothermic (They would cool the sea surface). Cooling of the sea surface on a global scale would draw in CO2 from the atmosphere. As Plankton can double in population in just one day the cooling would double everyday until some other factor slows the doubling. 1,2,4,16,32,64,128,256,512,1024, … If this rain of dust is both large and lasts for two years like the NASA video suggests then there may not be much atmospheric CO2 left.



Even if it worked one would have to produce the iron without emitting more CO2 than the algae would consume.
I suggest these funny solar furnace contraptions for that.
Doubling the income tax should suffice to build enough of them.


siliggy says:
June 12, 2013 at 3:45 pm
“are endothermic (They would cool the sea surface). Cooling of the sea surface on a global scale would draw in CO2 from the atmosphere. As Plankton can double in population in just one day the cooling would double everyday until some other factor slows the doubling. 1,2,4,16,32,64,128,256,512,1024, …”
Nice! Obviously a positive feedback, cooling the ocean each day as much as during all previous days, accelerating ever more, like a stock market crash, resulting in Icehouse Earth!


if iron was produced by some green agenda… would be pollution and they would be doing their best to tax/remove it
What morons….add iron….phosphate becomes limiting
…add iron and phosphate….nitrates become limiting
…they act like all they need is iron to grow a plant


OMG a self balance system is self balancing?


They’re talking about stealing CO2 from my pepper plants and I will have smaller and fewer chile rellenos. Can’t they leave well enough alone?

Tilo Reber

I just ran into a presentation on the CO2 cycle in ice cores and in modern instrument measurements, and how they tie together. In addition it discusses the correlation between CO2 and temperature as well as man made CO2 and the overall energy budget. The presentation was given by Prof. Murray Salby from Macquarie University in Australia, and it was given to a German audience. The information that it contains is both novel and seemingly indisputable. I thought that the presentation was truely excellent and more than worth the time. So here is the link where I found it.

Tilo Reber
Evan Thomas

There is a huge amount of iron ore mining in the Pilbara region – western area of Western Australia – which creates mountains of dust which drift into the Indian Ocean when easterly winds prevail. Will this affect the microbiology of this ocean? Cheers from sunny Sydney

An algae “bloom” is but one of many sorts of population explosion that can occur in the sea. They are perhaps explainable with 20-20 hind sight, but usually no one sees them coming.
Perhaps the most predictable population explosion occurs off the coast of Peru, as a warm El Nino gives way to a colder La Nina. As all the cold water comes welling up from the deeps, it is full of nutrients that rain down on deep waters from above, and this nourishment feeds life up at the surface. A sea which was nearly fish free during a El Nino is abruptly crowded with fish during a La Nina, however even then you cannot be sure which fish will be the winner. It is my understanding that the fishermen of Peru sometimes find their nets brimming with sardines, but other years find them brimming with anchovies. No one is sure why one species predominates.
A very neat population explosion can involve soft shelled clams, on a beach which has been practically clam-free for decades. (Clammers are very secretive when they find such a beach, as they don’t want to share.) I saw it happen back in the 1960’s on Basset’s Island in Buzzard’s Bay. You got a hint it was coming because the year before the sand was full of tiny, useless clams about half the size of a pea. The next year they were full grown and so close together some bumped each other. You could fill a pail in a couple minutes. I had the beach all to myself for a couple weeks, but once word spread it was wall to wall people, all digging.
The strangest population explosion I ever saw involved a little worm that lives in the muddy clam-flats up in Maine. They are like the worms used for bait when fishing at sea, with the frill of red arms along each side, only these worms are smaller and shorter. It turns out they can use those arms like oars, and zip about the water at a remarkable speed. In the evening I used to sit on a dock that had a floodlight shining down into the water, and one night the harbor was swarming, clotted with zipping worms, and the next night they were gone.
I think people should only promote a oceanic population explosion with extreme caution, and after carefully studying the countless repercussions. If one species has a population boom, the species that feeds on them will profit, however rival species will suffer and preditors that feed on those rivals will also suffer. For example, midst the many species of plankton floating in the soup of the sea are baby codfish, which begin life so tiny you need a magnifying glass to see them. If you promoted an algae bloom you might wipe out a fishery.
Another strange thing is that when you depress a population, such as the population of codfish, it doesn’t spring back when you cut back on fishing. There are factors involved in the ecology of the sea that we don’t come close to understanding. I discuss this briefly at

john robertson

So what were the results of the born again environmentalists who dumped a ship load of iron dust into the sea off of the Queen Charlotte Islands last year?


Mike jarosz says:
June 12, 2013 at 3:01 pm
This gap in our knowledge, combined with renewed interest in iron fertilization as an approach to the current climate crisis, makes it crucial that we have an improved understanding of iron cycling in marine systems,” Ingall said.
What climate crisis?
The one that if you forget to mention you dont get funding for your study.

Go Home

From a famous philosopher…
“There are known knowns. These are things we know that we know. There are known unknowns. That is to say, there are things that we know we don’t know. But there are also unknown unknowns. There are things we don’t know we don’t know.”
My fear is these idiots of climate science only have this as their philosophy… “There are known knowns. These are things we know that we know.” And they are probably wrong on that count also.

Mike Wryley

Welfare for diatoms, we all know how that turns out. In no time there will be a proliferation of single diatom families, illegitimate diatoms and big fat diatoms that can’t seem to find iron on their own anymore.

Crispin in Waterloo

The first time iron fertilization was tried in the 80’s it was very successful – so much so that it attracted the attention of the Green lobby. There was nothing like the current understanding about the chemistry and species involved – but scream they did anyway. Why? Because it offered an amazingly cheap and easy way to remove CO2 from the atmosphere, that’s why.
Now the argument is that adding iron is going to ultimately reduce the removal of CO2. What rubbish. The obvious implication is that removing iron would favour the CO2 eating critters. Is that right? Adding iron reduces CO2 removal so removing iron would have the opposite effect, yes? More CO2 absorbed?
Adding water to fields makes the weeds grow faster so don’t irrigate. Fertilizing plants makes them grow faster using up all the……..fertiliser.
The lunatical response to the iron experiment off the coast of Canada was just as baseless as the first one. Ever seen a reddish brown river emptying millions of cubic meters a day into the ocean? Maybe you’ve heard of the Mississippi or the Amazon? That’s iron oxide. It feeds the critters what feeds the phytoplankton what feeds the fish. They don’t want CO2 out of the air they want money.

Crispin in Waterloo – yes it was all about money.
The Haida Quaii tried “dusting” the ocean with iron last fall much to the horror of many:


Old ground.
Hoser says:
February 2, 2011 at 9:01 am
Is 25 billion tons of carbon per year dropping to the ocean floor without fertilization insignificant? And how much iron do we need to drop over 361 million km^2 to boost that amount – every year?
You need to provide 4nM iron (1). Assuming 1 m depth for each m^2 of area, you need 223 mg/m^2, or 223 kg/km^2. To fertilize the entire ocean requires 81 million tons of Fe, or 219 million tons of FeSO4. At 2840 kg/m^3, you need 77 million m^3 of iron sulfate. The iron dissipates within 3 days of last application. How many times per year do we want to do this?
Coale, et al. (1) recognize the challenge of scaling up their experiments. “[A] mesoscale enrighment experiment in these Southern Ocean waters poses a tantalizaing, yet formidable, challenge.”
Iron fertilization of every square kilometer of ocean is not possible or necessary, however, it certainly would be necessary to deliver iron monthly or more frequently to the selected ocean regions to have any lasting effect. Furthermore, to achieve any significant impact on atmospheric CO2 concentrations, a majority of ocean surface area in the most productive regions would need to be treated.
It is amusing to see what happens when laboratory-scale thinking has to meet the reality of the real world.
And what’s your carbon footprint to deliver all that iron?


So let’s see if I understand this correctly. We have a shortage of iron in the oceans right now. Why else would we want to seed some. Those critters we want to feed are still alive even though those other critters we don’t like grabbed all of the iron cookies off the table? Green cheese.


Wayne Delbeke says:
June 12, 2013 at 9:04 pm
“Crispin in Waterloo – yes it was all about money.
The Haida Quaii tried “dusting” the ocean with iron last fall much to the horror of many:

Interesting. All the screaming by the Guardian and by the UN etc. means, they don’t want anyone to meddle with their scam, it’s THEIR scam and they will decide how to pillage the populous and where to hide the carbon credit dollars.
The best line is
” Using the ocean as a carbon sink can cause ocean acidification”
which shows that University of Victoria climate scientist Andrew Weaver has no knowledge about what photosynthesis actually is.

Gene Selkov

All this talk about iron fertilisation only makes sense as long as it is known for certain that iron is a limiting factor. Even if it is, by flooding a cell’s iron requirement, you simply hit the next limit. It may be cobalt or zinc. Maybe the present cobalt requirement trumps the iron one, so no amount of iron thrown in will have any effect. One can’t know that without doing a meticulous research of that particular site and its inhabitants. For each type of cell, there are hundreds of factors limiting its growth, and then there are interactions between the species, making the situation all but inscrutable.


We are again trying to interfere in a system we little understand. This will lead to more problems that it is committed to solve.
It is not as if we are on a planet short of iron either, and this situation must have happened before and the seas still live, the planet is still here.

Gary Pearse

We have to somehow bring a more rapid end to this dangerous foolishness. The ocean and its inhabitants have a long relationship in cyclic balance and unbelievably hare-brained schemes involving billions of tons of anything added to the sea WILL have unintended consequences- we don’t need scientific studies to tell us this. Fortunately iron is not cheap to produce, transport and spread so we are saved from any significant scale projects of this kind by the Luddites in universities and scientific institutions where these ideas come from. What a sight to behold – billions of tonnes of iron ore strip-mined and transported by unit trains and ships (probably we will produce the CO2 we need in the process!) without an environmental protest!! I’m in the mining industry and I find this scary.
Why is it always the biologists who on the one hand are saving the ‘snail darter’ from a hydro dam
and on the other coming up with these ridiculous schemes? This is sufficient for a mass psychosis diagnosis.


Gene Selkov says:
June 13, 2013 at 3:09 am
Gene, this is more grade school science project…..
….they just discovered what causes red tides
..but you’re exactly right