Taiwanese Researchers Dismiss Iron Fertilisation Carbon Capture

Upper Klamath Lake cyanobacteria bloom. Photograph by U.S. Geological Survey
Upper Klamath Lake cyanobacteria bloom.
Photograph by U.S. Geological Survey

Guest essay by Eric Worrall

Taiwanese researchers have poured cold water on the possibility of capturing carbon with artificial algae blooms, created by fertilising the oceans with iron. The problem appears to be that the artificial algae bloom depletes other essential ocean nutrients, causing a reduction in algae growth elsewhere in the ocean.

To alleviate the impact of global warming, scientists have proposed a hypothesis of ā€œiron fertilization,ā€ assuming that adding iron into the ocean can boost the growth of algae to absorb the carbon dioxide in the air.

However, researchers in Taiwan have found flaws in this hypothesis.

Working with Columbia University, a NTU research group led by Haojia Abby Ren, associate professor of Geosciences at National Taiwan University (NTU), has poured iron into 12 waters around the globe to perform experiments on the ā€œiron fertilizationā€ hypothesis. It turned out algae only thrives in one-third of the areas tested.

The growth of algae requires nutrients other than iron, such as nitrate and phosphate. With the growing amount of algae, consumption of these nutrients also increases in the area. But when currents carry the algae to other waters, the nutrients become relatively scare elements, making algae hard to grow.

Read more: http://international.thenewslens.com/post/312664/

This claim is backed by an earlier study, which suggests that increased iron outflows into the ocean during the last ice age, caused by glaciers scraping iron rich minerals into the sea, did not increase algae growth in equatorial regions, because increased algae growth in subantarctic zones depleted other ocean nutrients.

The abstract of the study;

No iron fertilization in the equatorial Pacific Ocean during the last ice age

The equatorial Pacific Ocean is one of the major high-nutrient, low-chlorophyll regions in the global ocean. In such regions, the consumption of the available macro-nutrients such as nitrate and phosphate is thought to be limited in part by the low abundance of the critical micro-nutrient iron1. Greater atmospheric dust deposition2 could have fertilized the equatorial Pacific with iron during the last ice ageā€”the Last Glacial Period (LGP)ā€”but the effect of increased ice-age dust fluxes on primary productivity in the equatorial Pacific remains uncertain3, 4, 5, 6. Here we present meridional transects of dust (derived from the 232Th proxy), phytoplankton productivity (using opal, 231Pa/230Th and excess Ba), and the degree of nitrate consumption (using foraminifera-bound Ī“15N) from six cores in the central equatorial Pacific for the Holocene (0ā€“10,000 years ago) and the LGP (17,000ā€“27,000 years ago). We find that, although dust deposition in the central equatorial Pacific was two to three times greater in the LGP than in the Holocene, productivity was the same or lower, and the degree of nitrate consumption was the same. These biogeochemical findings suggest that the relatively greater ice-age dust fluxes were not large enough to provide substantial iron fertilization to the central equatorial Pacific. This may have been because the absolute rate of dust deposition in the LGP (although greater than the Holocene rate) was very low. The lower productivity coupled with unchanged nitrate consumption suggests that the subsurface major nutrient concentrations were lower in the central equatorial Pacific during the LGP. As these nutrients are today dominantly sourced from the Subantarctic Zone of the Southern Ocean, we propose that the central equatorial Pacific data are consistent with more nutrient consumption in the Subantarctic Zone, possibly owing to iron fertilization as a result of higher absolute dust fluxes in this region7, 8. Thus, ice-age iron fertilization in the Subantarctic Zone would have ultimately worked to lower, not raise, equatorial Pacific productivity.

Read more: http://www.nature.com/nature/journal/v529/n7587/full/nature16453.html

It might still be possible to deplete atmospheric CO2 using algae blooms, but you would have to somehow ensure the blooms received a balanced diet, and didn’t deplete the rest of the ocean of other essential nutrients. Manufacturing some essential fertiliser nutrients, such as nitrates, is extremely energy intensive.

Perhaps we should build more coal power plants, to produce the balanced algae fertiliser required to safely fixate all that carbon.

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ClimateOtter
April 17, 2016 4:33 pm

So the choice is between Chum Bucket and the Crusty Crab?

Tippy Hedron
Reply to  ClimateOtter
April 19, 2016 2:53 pm

Chum is Fum!

Latitude
April 17, 2016 4:37 pm

..and it took how many years and how much money for them to discover the obvious
Then the threw iron out in the middle of the ocean….and have no idea how phosphorus mines got on land
………..abyss

Katherine
Reply to  Latitude
April 17, 2016 5:55 pm

Here we present meridional transects of dust (derived from the 232Th proxy), phytoplankton productivity (using opal, 231Pa/230Th and excess Ba), and the degree of nitrate consumption (using foraminifera-bound Ī“15N) from six cores in the central equatorial Pacific for the Holocene (0ā€“10,000 years ago) and the LGP (17,000ā€“27,000 years ago).

Sure doesn’t sound like they threw any iron.

Latitude
Reply to  Latitude
April 17, 2016 6:55 pm

dust = iron

Crispin in Waterloo
April 17, 2016 4:44 pm

It is not reasonable to say that the overall productivity would drop if it was fertilised with iron. How can growth go up where it is fertilised and not just offset, but actually drop more that the fertilised portion elsewhere?
This smells of a setup. They are trying to find a reason to kill an obvious and effective way of increasing ocean productivity. BTW the claim it can’t be allowed (I think from Greenpeace) in the early ’80’s was made without a shred of evidence that harm resulted. This piece basically says ‘we think there is harm’. Or potential harm, or maybe harm, or probably harm, but we are speculating.

Bill Hunter
Reply to  Crispin in Waterloo
April 18, 2016 12:09 am

Pretty good question of just how equatorial nutrients are consumed by antarctic algae. A lot of use of the word “may” in this study. Probably the number one earmark of whats wrong with academic science selling themselves out as stalking horses.
Accountants can’t get away with the word “may” without a lot of quantification and/or qualification.

April 17, 2016 4:47 pm

This is of course their opinion. Nothing more.
I call your attention to Russ George and his experiment that pissed off the science world, created a huge plankton bloom, which resulted in record returns of Salmon in the Pacific Northwest.
Did Russ George’s Geoengineering experiment actually work?
http://www.treehugger.com/environmental-policy/did-russ-georges-geoengineering-experiment-actually-work.html
And this.
Ocean Pasture Plankton Collapse Cataclysmic Say German Media ā€“ Russ George responds
Reuters Special Report: Experimental climate fixes stir hopes, fears, lawyers
August 30, 2013 Canada, National
Last year the Haida, an indigenous group in Canada, set out to increase their salmon stocks and save the planet. Helped by American businessman Russ George, a group of villagers dumped 100 metric tons (110.23 tons) of iron dust from a boat into the Pacific Ocean. They that could promote fish numbers and absorb the greenhouse gas carbon dioxide from the atmosphere. Instead, in March, they were raided by Canadian officials for illegal dumping at sea.
http://www.reuters.com/article/us-climate-geoengineering-special-report-idUSBRE97T0BZ20130830
And this
Ocean Pasture Plankton Collapse Cataclysmic Say German Media ā€“ Russ George responds
http://fisherynation.com/archives/44975

Tom Halla
Reply to  borehead
April 17, 2016 5:30 pm

Interesting comment by someone whose tab I do not recognize, and have no experience with, to a reference I have never heard of. Nice prima fascie case that supplying the missing nutrients does work, but …..

les
Reply to  Tom Halla
April 17, 2016 5:59 pm

But what?… Given the millions of views this site gets, you expect to recognize the name? As for the event, anyone living in the Pacific Northwest heard of this on local and national news. Huge debates about the propriety or legiitamacy of it at the time; check the media from that period. while the debates raged about human manipulation of the ecosystem, there was no actual debate over the data and outcomes. Certainly by depleting nutrients in one area another is effected – but the net effect cannot be negative. They simply maximized the production of algae at points where it would be most beneficial to the food chain consuming it.

Reply to  Tom Halla
April 17, 2016 7:00 pm

I have left comment here periodically, and have been ignored! They were generally comments about NOAA and lousy science regarding fish, and stock assessments that are non inclusive of basic climate data such as water temps, that would support redistribution of fish stock, not depleted fish stock. I have tried to spark interest, based on hypocrisy. The agency that manipulates climate data, is also manipulating fish data. Who could figure?!?!

garymount
Reply to  borehead
April 17, 2016 6:12 pm

I have previously reviewed the literature of which you are referring to and the link to increased salmon just doesn’t hold up. For a scientific experiment, dumping the iron in that location was a lousy decision if you wanted to do research. Far better locations would have been preferential if one actually wanted to research the effects (so said the scientists in the articles I read ).

Reply to  garymount
April 17, 2016 7:13 pm

link to increased salmon just doesnā€™t hold up?
Dig in. It certainly did increase salmon returns in record numbers.
Personally. I’m about sick of reading the drivel of a lot of scientists.
I have a few that I know, and follow that their word is gold. They’ve earned that.

garymount
Reply to  garymount
April 17, 2016 8:16 pm

“I’ll go on record as saying that coincidence does not equal causality,” McNamee says. “I don’t believe in any way, shape or form that we definitely contributed to that salmon run. The question I have for salmon experts is this: ‘What changed in the ocean in 2012, the year prior, that had the potential to contribute to this massive return?’ The answer is I don’t know, but certainly our project may have contributed.”
http://www.earthisland.org/journal/index.php/elist/eListRead/impact_of_last_years_rouge_ocean_fertilization_experiment_still_unclear

urederra
Reply to  borehead
April 18, 2016 1:36 am

a group of villagers dumped 100 metric tons (110.23 tons) of iron dust…

I didn’t know that you guys have short tons and imperial or long tons.

Slacko
Reply to  urederra
April 19, 2016 3:51 am

They also have a short gallon (a little over 7 pints) which is well short of an imperial gallon.

April 17, 2016 5:38 pm

The idea of using iron fertilization to stave off the dreaded apocalypse has been around for a while, and, like so many concepts coming out of Climate Scienceā„¢, was proposed by people who never performed the simple experiment (and who probably didn’t really know much about chemistry, or biology,or physics, or geology, which seems to be a not uncommon condition among Climate Scientistsā„¢). These people did the experiment. Good for them. It’s a bad idea. Move on to something useful.

Reply to  Smart Rock
April 17, 2016 7:16 pm

Tell that to the starving herring in the Gulf of Maine!
http://fisherynation.com/fish-northwest-atlantic-going-hungry-new-science-maines-department-marine-resources-helps-explain
Written by a fisherman. What the Hell do they know?!!

Reply to  Smart Rock
April 21, 2016 3:00 pm

I knew John H. Martin, and you’re no John Martin.
ā€œGive me a half tanker of iron, and I will give you an ice age.ā€
http://earthobservatory.nasa.gov/Features/Martin/

David L. Hagen
April 17, 2016 5:44 pm

3D Farming Oceans for Food & Fuel
Lets focus on real needs of supplying fuel and food – then innovators can accomplish incredible things – (rather than trying to mitigate imagined climate horrors.)
Judith Curry highlights:
How an Army of Ocean Farmers are Starting an Economic Revolution

Our 3D farms are designed to address three major challenges: First, to bring to the table a delicious new seafood plate in this era of overfishing and food insecurity; second, to transform fishermen into restorative ocean farmers; and third, to build the foundation for a new blue-green economy that doesnā€™t recreate the injustices of the old industrial economy. . . .
We can grow incredible amounts of food in small areas: 25 tons of greens and 250,000 shellfish per acre in five months. If you were to create a network of our ocean farms totaling the size of Washington state, you could feed the planet.
This is zero-input food that requires no fresh water, no fertilizer, no feed, no arid land. It is hands down the most sustainable food on the planet.. . .
Seaweeds could be a powerful source of zero-input biofuel; feasibility studies suggest we might produce 2,000 gallons of ethanol per acreā€Šā€”ā€Šthatā€™s a 30 times higher yield than soybeans and five times more than corn. According to the Department of Energy, if you were to take a network of our farms equaling half the size of the state of Maine, you could replace all the oil in the United States. . . .

SMC
April 17, 2016 5:50 pm

Sounds like an excellent use for pig poo… Farmers wouldn’t have to store it long term or have it treated. Mix in a little extra iron and BOOM… algae bloom. Of course, nobody has really talked about the unintended consequences of geoengineering… on any scale. The powers that be are too wrapped up in mitigating the evil CO2 at all costs to worry about consequences.

Editor
April 17, 2016 6:00 pm

I find the underlying logic to be deficient in iron, which is leaving it floppy and spineless.
Their claim is like a farmer saying “adding nitrates to the soil for vegetables doesn’t work, because they start to grow, and then after while they run out of phosphate” … so what?
Seriously, so what? Is there an actual farmer in this world that wouldn’t go “Man, now I’ll add phosphate as well and really get good production!”?
w.

Latitude
Reply to  Eric Worrall
April 17, 2016 7:01 pm

cyanobacteria fix nitrogen….it would be phosphorus in the open ocean that would be limiting..and it already is

urederra
Reply to  Eric Worrall
April 18, 2016 1:50 am

Well, Volkswagen cars can fix nitrogen.

urederra
Reply to  Eric Worrall
April 18, 2016 2:31 am

I was not joking about the cars. Here is an article published at NASA website about NOx produced by lightning:
http://www.nasa.gov/topics/earth/features/nox_lightning.html
Some points worth mentioning:

According to a new paper by Ott and Pickering in the Journal of Geophysical Research, each flash of lightning on average in the several mid-latitude and subtropical thunderstorms studied turned 7 kilograms (15.4 pounds) of nitrogen into chemically reactive NOx. “In other words, you could drive a new car across the United States more than 50 times and still produce less than half as much NOx as an average lightning flash,” Ott estimated. The results were published July.

and this one is priceless:

“Lightning is one of the smaller factors for surface ozone levels, but in some cases a surge of ozone formed from lightning NOx could be enough to put a community out of compliance with EPA air quality standards during certain times of the year,” said Pickering.

ozspeaksup
Reply to  Eric Worrall
April 18, 2016 6:38 am

so why not do this near the areas they keep yelling have excess nitrogen/phosphorus farm and other cause like sewage.. runoff I wonder?

Bill Treuren
Reply to  Willis Eschenbach
April 17, 2016 7:59 pm

The argument should be where is the best place to optimize food or CO2 sequestration.
It is perfectly obvious that we as humans deplete the oceans of nutrients through fishing, the question should only be about how much to return and where. The extended question for the advanced students should be focus on can we do more with this once we understand it.

Reply to  Bill Treuren
April 17, 2016 8:18 pm

It is perfectly obvious that we as humans deplete the oceans of nutrients through fishing.
Obvious?
What you really mean is eating fish removes carbon from the ocean.
Eat more fish. Remove more carbon.

Bill Hunter
Reply to  Bill Treuren
April 18, 2016 6:32 am

Exactly what the boneheads don’t get is that inaction to mitigate is worse. Not that I think CO2 needs sequestering in the ocean, what needs to be considered is how to keep things in balance. . . .the answer is mitigation whether it be population control or enhancement of that which we deplete.
The abstract suggests that iron fertilization won’t work because the ocean was not more productive duing the last glacial period with more iron. Seems like one of those warmists type conclusions. . . .must be CO2 because we are too stupid to think of anything else. Perhaps all can be explained by sunlight variation.

Analitik
April 17, 2016 7:04 pm

Why do they focus on the Pacific region not being receptive to iron induced algal blooming? Surely the net global effect is the important result and if blooms occur in subantarctic zones, then isn’t that an “improvement” on the current situation?
This all presupposes that CO2 sequestration is actually important, of course.
I’m sure there was a post similar to this a few months back, based around a study by about 50 authors from the Columbia University.

TA
Reply to  Analitik
April 18, 2016 8:55 am

“This all presupposes that CO2 sequestration is actually important, of course.”
Exactly! We need to keep focused! šŸ™‚

crosspatch
April 17, 2016 7:19 pm

How many tons of iron were put into the ocean during WWII? I am guessing a large amount of that is still in the process of decomposing. Doesn’t appear to have made much difference.

Mike the Morlock
April 17, 2016 7:20 pm

Eric Worrall
There things that seen odd about this paper.
In your first link it seems to make this a mainly Taiwanese paper but all the rest of the authors are form the U.S. most from Columbia U. The Corresponding author K.M. Costa is from Columbia U. Strange to say the least.
Next, while the first link talks about experiments it twelve locations I cannot find it in the abstract. Did they actually do the experiments?
It the thread there is a link by borehead April 17, 2016 at 4:47 pm of a experiment off the British Columbia coast which seems to contradict these authors findings.
Sorry it leaves me wondering who’s paper this really is. BTW Haojia Abby Ren, she did her PHD at Columbia.
http://international.thenewslens.com/post/312664/
http://www.nature.com/nature/journal/v529/n7587/full/nature16453.html
michael

DonK31
April 17, 2016 7:35 pm

Around here (SW FL) anything that causes algae blooms is condemed because the algae suck up all the free Oxygen in the water, causing fish to suffocate. Read about Red tide and fish kills.

Mike the Morlock
Reply to  Eric Worrall
April 17, 2016 8:45 pm

Thanks
michael

noaaprogrammer
April 17, 2016 9:19 pm

And the angel poured out his vial into the sea and it turned to blood [iron oxide], and all the creatures of the sea died. Rev. 16:3 = Catastrophic Angelic Global Warning

Reply to  noaaprogrammer
April 18, 2016 2:28 am

Wasn’t that red algae? Quite toxic for sea life…

April 17, 2016 9:51 pm

Nature is way ahead of anything mankind can do
http://theconversation.com/how-australias-biggest-dust-storm-went-on-to-green-the-ocean-47695
2.5 million tons of iron-laden dust in one storm (with the obligatory ‘climate change will make it worse’

Khwarizmi
April 17, 2016 10:15 pm

The idea that dead things just fall to the bottom of the sea to be locked up in the sediments is a fossil fueled fantasy. It leads to people spending millions on stupid experiments with predictable results.
“Oh no! My carbon capture experiment got eaten! Who would have thought?”
https://wattsupwiththat.com/2009/03/27/ocean-iron-fertilization-experiment-a-blooming-failure/

tty
Reply to  Khwarizmi
April 18, 2016 10:12 am

They do fall to the bottom, though most get eaten on the way down and the rest usually get eaten on arrival. Organics accumulating on the bottom is pretty rare and really only happens when the bottom water is oxygen-free.

Gary Pearse
April 17, 2016 10:35 pm

Iron in alkaline seawater has a low solubility. There is no scarcity of iron availability with terrestrial rocks averaging about 15% (weathering and stream sediments) and oceanic crust being largely basaltic which is similarly 10-15%.
Ocean basin basalts are made porous by bacterial action that releases soluble iron etc. Depletion of existing dissolved iron is thereby replenished. Calcium is similarly of very low solubility and with similar abundance of source materials to iron and yet carbonate shells, bones of vertebrates etc are abundant in the sea.
Phosphorus and nitrogen sources are also ubiquitous with river water, phosphate sediments, plant detritus, agriculture runoff etc. Huge phosphorite formations occur around the world that were once sea sediments containing fossil shark teeth and other indicative fossils. Nitrates also are formed by thunderstorms and fall with rainwater. Fish and mammals in the sea don’t have any problems making bones and teeth.
At some cost all 92 elements can be removed from seawater and biota are particularly adroit at absorbing what they need. I think it is time to have a moratorium on all these linear thinking, simpleton, testube, half-baked ocean studies and get a grip on the magnitude of the problems in fathoming the countless interrelated organic and inorganic reactions, extractions, and physico-chemico-biologico symbiotic activities going on in oceans as a backdrop to the quality of experiments you can do and what degree of certainty you can have. The fact that it is easy to point out the silliness with examples that come readily to hand is a measure of how out of their depth most of these ocean scientists are.

tty
Reply to  Gary Pearse
April 18, 2016 10:15 am

Actually phosphorus is rather scarce in the ocean. The only places where it is available in reasonable quantities are upwelling areas. All those marine phosphorite rocks were once beneath upwelling areas.

Gary Pearse
Reply to  tty
April 18, 2016 1:41 pm

Carbonic acid in rain and fresh water delivers lots from the land. Florida, Morocco, much of West Africa, virtually every continent has literally billions of tons and hundreds of millions of tons are produced each year and spread on the land much to the chagrin of you and your conference probably.
Trust me, this is a very abundant element used by every plant and animal which surrenders it to the environment to be used again and again.
Here is a useful thing to know that will put you head and shoulders above your acquaintances and apparently many scientists. There is no shortage of any resources on land or in the sea. Surely if 400 ppm CO2 scares the he’ll out of you, what appears to be a shortage in the sea should make you think. The sea is the ultimate sink. It is basically pretty much in equilibrium in its composition. It’s had several billion years to to get there.

Gary Pearse
Reply to  tty
April 18, 2016 1:43 pm

Confreres, not conference

Gary Pearse
Reply to  tty
April 18, 2016 2:00 pm

Carbonic acid in rain and fresh water delivers lots from the land. Florida, Morocco, much of West Africa, virtually every continent has literally billions of tons and hundreds of millions of tons are produced each year and spread on the land much to the chagrin of you and your confreres probably.
Trust me, this is a very abundant element used by every plant and animal which surrenders it to the environment to be used again and again.
Here is a useful thing to know that will put you head and shoulders above your acquaintances and apparently many scientists. There is no shortage of any resources on land or in the sea. Surely if 400 ppm CO2 scares the he’ll out of you, what appears to be a shortage in the sea should make you think. The sea is the ultimate sink. It is basically pretty much in equilibrium in its composition. It’s had several billion years to to get there.

April 17, 2016 11:56 pm

Using iron fertilization in the oceans to reduce CO2 is as sensible as the idea of importing rabbits, Cane Toads and Picky Pear to Australia. Who will clean up the mess when these fantastical, unresearched geo-enginering schemes go pear shaped.

David Chappell
April 18, 2016 12:31 am

Whenever man interferes with Mother Nature, she always comes back to bite him on the bum. Leave well alone.

April 18, 2016 3:27 am

Personally I find such large scale alterations to systems naturally evolved over millions of years scary.
Natural evolution has natural checks and balances, buffers and limiters because that is how there are oceanic ecology.
Making half baked alterations to large bodies of water, with our currently level of understanding, could well lead to unforeseen disaster.
A little information is a dangerous thing! Not enough information for such plans, and there are already private enterprises doing this Iron seeding, it’s happening.
One thing, when is someone going to mention cloud seeing in this whole climate debate, that is also happening around the world

Reply to  Mark
April 18, 2016 3:28 am

*Cloud Seeding

Bruce Cobb
April 18, 2016 5:07 am

Not this again. Stupid, on a logarithmic scale. Next they’ll be adding soap to ocean-going ships’ wakes to increase labido albedo, or other, insanely stupid things.
I sometimes think they come up with these insane, idiotic, and frankly frightening “solutions” to a non-problem to scare people into accepting mitigation.

Dudley Horscroft
April 18, 2016 5:36 am

I find that urea can be decomposed by suitable bacteria into ammonium ions and nitrite ions which can then be decomposed into nitrates. Where is urea readily available? In urine.
Faecal matter is largely dead gut bacteria, and is a good source of nitrogenous matter. Where is that available from?
It seems the solution is putting human and animal wastes into the oceans, carefully spread, so as not to overload any particular area. The International Maritime Organization has rules about this, and large passenger ships are already busily fertilizing the oceans.

April 18, 2016 7:15 am

Can someone please explain to me how these “brainstorming” and back of the napkin ideas get headlines?
Also, did none of these people take Chemical Oceanography? How bout any class that talks about the water cycle on the Earth–I learned about the problems with algae blooms in 7th grade Earth Science class and they want to create one to do what? Continue starving the plant life on Earth and accelerating the animal extinction by suffocating them?
Do these people not put 2 and 2 together? The Earth is an immensely complex system that we do not fully understand. We understand bits and pieces and it’s high frigging time these “scientists” start learning about the OTHER bits and pieces before interjecting nonsensical notions onto the public at large and saying they “decided” against that because it would cause bigger problems. So if you decided against it, why the hell is it news?
Remember when those kinds of ideas stayed shelved or got thrown away at the end of lunch? Now they are headlines. Ridiculous waste of time, web space and energy of everyone involved.

Dudley Horscroft
Reply to  Jenn Runion
April 19, 2016 10:30 pm

Jenn Runion said: “So if you decided against it, why the hell is it news?”
When a scientific experiment gives the results you want, it is OK to trumpet it. When it does not, it is equally important to publish it so that others are not led down a path which does not work, OR others are able to look carefully at your work and perhaps spot the flaw which prevented your experiment being a success.
We have seen pharmaceutical companies black-marked because they only publish their success stories. Failures should be published as well.

tadchem
April 18, 2016 8:03 am

Most marine iron comes from ocean floor vulcanism, compared to which man-made iron fertilization would remain trivial, and would only be expensive for humanity – a wasteful diversion of resources. The most effective CCS comes from plankton, not algae, and results in carbon being sequestered as calcium carbonate in the skeletons of plankton, which sinks to the ocean floor when the plankton dies to eventually become limestone.

tty
Reply to  tadchem
April 18, 2016 10:18 am

Actually the calcium carbonate usually dissolves in the deep oceans where the bottom is below the CCD. Limestones are typically shallow water or coastal deposits.

Jerry Henson
April 18, 2016 8:13 am

I thought that the massive return of salmon in the ’80’s was due to massive
releases of fry in the in the “70’s.
http://e360.yale.edu/feature/hatch-22_the_problem_with_the_pacific_salmon_resurgence/2335/

Tony Garcia
April 26, 2016 2:12 am

Many valid points are made here, but some things are not being addressed, like asking why iron fertilisation works, and is there some process at work here that can be useful elsewhere? Nutrients can be made available to algae to make them bloom under controlled conditions, all that is required is that some use can be made of the resultant algae, i.e. they are harvested as opposed to being left to decompose and thereby remove oxygen from the ocean. I have been trying for sometime to create interest in the concept, to no avail.