Changing Planet

Iron Fertilization: Savior to Climate Change or Ocean Dumping?

Massive coccolithophore bloom in the Barents Sea. These blooms are caused by high levels of sunlight in the arctic summer, and the right combination of nutrients to allow growth. By Jeff Schmaltz (NASA Earth Observatory).

Unbeknownst to most scientists until a few days ago, two hundred thousand pounds of iron sulphate were dumped into North Pacific Ocean in July, with the aim to trigger a large plankton bloom. This experiment was conducted by the Haida Salmon Restoration Corporation, under the direction of businessman Russ George. Why dump this dirty brown powder into the ocean and why to trigger a plankton bloom? All in the name of reversing man-made climate change.

Phytoplankton is photosynthetic, needing sunlight and nutrients to grow, taking up carbon dioxide in the process and producing oxygen as a by-product. This phytoplankton then dies, falling to the bottom of the ocean, and taking that ‘sequestered’ carbon dioxide with it, trapping it at the bottom of the ocean. One of the major nutrients phytoplankton needs to grow is iron, an insoluble nutrient and often found in limited quantities, inhibiting large plankton blooms from occurring. So by adding iron to the ocean, we can increase the numbers of phytoplankton photosynthesizing, using up more carbon dioxide from the atmosphere and locking it up, deep in our oceans.

Or at least that’s the theory. Geoengineering is the term coined for deliberately modifying our environment to tackle man-made climatic changes on a global scale. It all sounds so simple – an easy route to solving our carbon emission crisis. The controversy comes that we don’t fully understand the consequences of manipulating our environment on a global scale, and we have to weigh up whether those consequences are better, or worse, than the problem we are trying to fix. We’ve seen what’s happened time after time when we’ve modified the food chain – fisheries collapses, extinction of species – we know well that connections that seem small can have drastic consequences we didn’t even consider. In addition, as that large bloom dies, decay will use up oxygen, potentially creating large anoxic zones, smothering important bottom habitats in the deep ocean.

The ‘experiment’ that was executed by George and colleagues is primarily under fire because it was done undercover, without scientific peer review or process, and without international collaboration, yet can have global consequences. It is also the largest iron fertilization experiment to have occurred anywhere – 200,000 pounds versus a few thousand pounds. Other smaller scale international experiments over the last fifteen-plus years have concluded that the sequestering efficiency is low (and sometimes no effect was seen) – the amount of iron you’d need to make even a slight dent in our carbon emissions is in the million tons per year, and even if you put in that amount, it may just not work. Unregulated iron fertilization on this scale could have dramatic consequences and goes against an international moratoria created by the UN to protect ocean environments. Far from being a savior, this experiment is being called a large scale dumping of waste into our oceans.

What do you think, was it a worthwhile test or badly handled? 

Dr. Rhian Waller is a professor of Marine Sciences at the Darling Marine Center (University of Maine, USA) and specializes in the ecology of deep-sea and cold-water organisms, particularly corals. Rhian has led or participated in over 40 international research and exploration cruises and expeditions to some of the most remote parts of the planet, and has published over 30 scientific papers and book chapters in her 9 year career. She is passionate about educating the next generation of scientists, and conserving our little known deep-sea and polar ecosystems to be studied and enjoyed in the future.
  • Broadlands

    Coccolithophore skeletons are made of CaCO3, calcium carbonate and this biomineral may survive rapid organic matter oxidative recycling. This could take some CO2 to the bottom as fossils (White Cliffs of Dover). However, the more commonly found silica skeleton diatoms and Radiolarians, as well as other phytoplankton without any skeletons, will take almost zero CO2 to the bottom for long term CO2 burial. It’s the LONG term burial of carbon that counts. Thus, iron fertilization of the oceans is a total waste of time, if not also money and resources.

  • albert rattelade

    the problem seems to point to unscientific decisions made by people who could never work for National Geographic…as a child.discovering a collection of out of this world magazine 50 years ago ,entered a new direction,became a camera nut and collector,dark room,naturalist tendencies,stange pets,began a life long passion for travel, working exotic gigs all over the world,Thank You National Geographic….i recycle discarded magazines and collect your maps for poor mayan villagers to inspire the young . your channel is here,the young just need inspiration….my cable is free but we only carry National Geographic and Discovery Channel and the boys in yellow tshirts and the girls in blue play soccer while i spout science and anthropology…my neighbors and i have a question for you…i participated in the columbus ,semana cay project for the 500 th anniversay and would national geographic do a similar endeavour for 500th when horses came to America and how they changed life

  • snewsom2997

    Well at least he didn’t pump SO2 at high Altitude to reflect the sun.

  • Alex

    If ocean fertilization is dangerous, why isn’t planting a forest as a carbon offset?

  • Philip

    All this effort on removing CO2 is wasted and counterproductive. It is not the CO2 from the burning of fossil fuels but the heat released from the burning that is causing global warming. The Toyota protocol totally ignored the heat released and its contribution and focused solely on the fact that CO2 is a greenhouse gas that can absorb radiation. If they had even considered the heat of combustion we would not be in the situation we are in today..,with nations, corporations, and individuals proposing ridiculous schemes for removing CO2. To have ignored the heat is grossly unscientific. For example energy usage for the year 2008 was 16 terrawatts, enough energy to equal 500 Mount Saint Helens eruptions. Don’t continue letting the CO2 myth go unchallenged.

  • @pdjmoo

    Russ George should be charged with violating the UN’s convention on biological diversity (CBD) and London convention on the dumping of wastes at sea, which both prohibit for-profit ocean fertilisation activities.
    If we don’t stand up and set an example now, more of this will occur — jumping into the already decimated environment of oceans and earth – require a collected scientific independent peer review from all disciplines — as to this day we humans do not know all the facts about how magnificent biosystem works, it’s crucial interdependencies and symbiotic relationships.

  • Carsten Troelsgaard

    Shouldn’t we expect more of this kind of vigilance … it may not be a surprise that President Obama supports more oil-production, but my own (Denmark) producer has announced a scale-up of their oil-explorations to raise their productivity.
    The fertilisation may be doobious in it’s knowledgebase, but the heading of world-leading countries is most definately in the wrong direction in spite of what IS known.

  • Shawn Bay

    It is unfortunate that the consequences of this large scale attempt at ocean fertilization may not only affect the health of the ocean, but there is a large social consequence as well. Russ George has convinced the village of Old Masset that the bloom that occurred will contribute to helping stave off a decline of salmon stocks. He has also convinced them that they will be able to sell carbon credits as a way of recouping the $2.5 million they poured into the project. $1.7 million dollars came from a parity grant that the village was given to do with what they felt necessary. Rather than put it into social programs, skills training, or even perhaps into a new recreation facility, they invested it into the project. Money was borrowed from the local Northern Savings Credit Union despite them doing their due diligence and rasing alarm with the inability to recoup their investment through selling carbon credits. The intentions of the Village of Old Masset may have been good, but I don’t think anyone did their due diligence here and they may pay for it for years to come.

  • humphrey

    I believe @Broadlands is correct. The SOFEX iron experiments showed iron based algal blooms were too quick to cause degradation. Historically large carbon deposits (ie coal) were created by mass die off events of terrestrial plants and carbon sequestration. I think we should study burying trees in abandoned mines with the rule of growing an equivalent amount of trees to logs buried

  • dudley dooright

    Since the past volcanic eruptions up north put salmon levels back to 50’s level’s on both major eruptions, it stands to reason, next year will either be mega salmon, but if not, will be a waste. Time will tell if Fukushima makes the salmon inedible or not. As far as carbon credits, that just won’t fly in the current climate of economic collapse.

  • Carsten Troelsgaard

    Shawn Bay, .. giving it a second thought after reading your input, I’ve come to realize that
    1) One cannot expect organic carbon to be sequestered at the deep ocean floor. The floor is on averaged oxygenated and not accumulating organic material.
    2) The accumulation of CaCO3 on the ocean floor is guided by the CCD (carbon compensation depth, the depth below which CaCO3 will be dissolved). Gerhard Einsele mentions a depth of 3,5 to 5,0 km (1992, numbers prior to detection of the ocean acidification)

    There is thus no reason to give carbon-credits to the endeavour, unless they can provide evidence that contradicts the above.

  • Jennifer Temple

    Any experiments in Geo-engineering could prove more catastrophic sooner. An example is in this “experiment”.If the oceans become oxygen depleted that is worse than losing the rain forests! The oceans are the lunges for life on earth. It is not as though we can say, “Woops! that wasn’t a good idea.” There is no going back.

  • Cynthia DeMone

    I have more of a question than a comment. Who what entity or government was going to pay for the carbon credits? And how was it presented to anyone that their case was made to earn such credits?

  • Jason McNamee

    I prefer to leave science to the scientists:

    Interestingly, plankton is pretty important to the planet: and:

    Unfortunately plankton is decreasing at a global average of 1%/year. No plankton = No fish :

  • Steven B. Krivit, New Energy Times

    How did Russ George convince these first nation villagers to part with their once-in-a-lifetime $1.7 million grant? How did he convince them that this “experiment” could permanently sequester greenhouse gasses? Or that they could turn their “investment” into a profitable carbon-credit scheme? Or restore the salmon? Did Russ George behave more like a scientist or like a penny-stock scammer?

    We don’t have the answers to these questions, but we did learn a lot about this man when we performed our investigations into his previous quasi-scientific attempts several years ago with low-energy nuclear reaction research (LENR) and his earlier failed attempt at massive plankton seeding. Readers can find an index of our investigations here:

  • Tracy Scanlon

    It sounds like our governments are trying to cheat on global warming, rather then our stopping of the use of fossil fuels and looking for other green solutions.It’s all about the money.They don’t really want un end to fossil fuels they just say that they do for appeasement and pacification.The only green they are worried about is the green in their bank accounts.

  • Ken

    Ok, seems to me that 1) climate change is potentially catastrophic and 2) we aren’t close to a world political solution that can undo the damage.

    So why is it a bad idea to experiment with ocean iron fertilization? The experiments are inherently localized and short term. And maybe this idea can help — anyway, after a few hours of reading about this stuff, it doesn’t sound completely wrong to me. Try googling on “Azolla event.”

    I’ve sailed around a lot of the world’s oceans, and the parts that have nutrient-rich upwellings support WAY more life than the rest — in deep water as well as at the surface. Why is this bad?

    I’m not defending Russ George. But shouldn’t we support a lot more legitimate, scientific research?


  • Mirza Fariha

    You should also give the importance of Iron Fertilization

  • Martyn

    It seems like everyone is a voice on what we shouldn’t do, yet no-one is reviewing what we are doing to the oceans.

    We can not keep plundering the seas of life on such an industrious scale, and poisoning our atmosphere with carbon. I think Russ George is attempting to redress the balance. Either way, there is no disputing that iron is key to plankton, plankton is key to marine (and non-marine) life.

    Besides the potential for poisoning, my issue with this experiment is that it doesn’t seem to have been leaped upon by eco-scientists. This experiment has happened, whether we like it or not – but it looks like no-one has used this episode to monitor what does happen to the eco system.

    An opportunity has presented itself to categorically state whether iron fertilisation is a viable option for carbon dioxide reduction and marine life promotion.

    It seems like most people are just using it as an opportunity to bash Russ George (Mr Krevit, I’m looking at you)…

    …at least Mr George can say “I didn’t stand back and watch”.

  • MfK

    Let’s see. The total mass of iron sulfate dumped into the ocean was 200,000 pounds. The total mass of the ocean is about 3,391,440,000,000,000,000,000 pounds. So they altered the ocean’s content by 5.9×10^-15 percent. That isn’t within detectable limits. However, the experiment did result in a huge spike in the salmon catch. So your problem is…what?

  • David @

    THIS is a great basis for a feel good, independent film screenplay, a la The Full Monty or that Whale movie with Drew Barrymore. Hollywood take note.

  • ANBA

    Need some more trial,Anyhow it is excellent

  • Joe Neubarth

    The amount of CO2 presently in the atmosphere is sufficient to raise Ambient Average Temperature by 4 to 6 degrees centigrade in the next few years. The additions of Methane to that CO2 will raise temperature even more. In about two to three years the world will panic and revisit this topic. When the choice is massive human death or pollution of the ocean humans will vote for their preservation first.

  • ur mans

    hi everyone I just wanted to say BOYEEEEEEE!


    If some wrk is to be done pefect monitoring must be Made since it has no. Side effects to the environment either to the living organism in ocean if phytoplankton is left as such without any proper removal of their dead organism

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  • prakash

    Thank you fr sharing this was very helpful, Keep sharing information
    We do export iron powder to India and other countries visit our website for more details

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