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May 03, 2007

Seeding the Oceans

Looks like this first large scale trial of seeding the oceans is to go ahead.

Planktos, an environmental company based in California, hopes to create a bloom of 50-60 million tonnes of which, it estimates, up to 20 per cent will sink, taking with it 3-5 million tonnes of carbon.

The trial is to be carried out in international waters 350 miles west of the Galápagos Islands. Previous research has shown that iron seeding can encourage a plankton population explosion but scientists have met with mixed results.

Planktos intends to drop up to 100 tonnes of iron, despite concerns in the scientific community. If successful the project will open up iron seeding to the carbon offsetting industry, giving firms an alternative to planting trees to compensate for the carbon emissions blamed for global warming.

Yes, it's an experiment, no, we don't know whether it will work (that's why it's an experiment, see?).

However, let's run some numbers to see the effects if it does, shall we?

OK, The Stern Review says that CO2 costs $85 per tonne in damages from the emissions. Just to keep the maths simple we'll call that $100 per tonne carbon (not correct, but hey, this is back of the envelope stuff).

So we're hoping to take 3 million tonnes of carbon out of circulation. That's $300 million's worth of damage averted.

Obviously, this experiment and the 2 year monitoring period are going to cost a lot of money but we're in fact doing this with 100 tonnes of iron powder.

So, how much does iron powder cost?

Now there are a few iron powder plants around the world making more than 100 000 tonnes yearly, and the largest one, the Hoeganaes Corporation's Gallatin plant, has a capacity of 350 000 tonnes. The increase in scale of iron powder operations obviously has had an effect on production costs. As a result the ratio between the price of iron powder and that of steel has gradually been reduced. The competitive strength of ferrous PM has been increased, but the price of iron powder is still about double that of wrought steel.

With hot rolled steel (which I'll use as a guide to wrought) around the $500 per tonne mark, that gives us $1,000 per tonne iron powder.

Or, in material costs for this action, $100,000.

So, by sticking $100,000 worth of iron powder into the ocean we can stop $300,000,000 worth of damage from CO2 emissions.

So, yes, assuming that the technology actually works, we seem to have found a cost effective way of dealing with emissions. Something like 3.3 cents per tonne carbon in fact.

One factory (and there's nothing very difficult about making iron powder, so we can build more and there's no shortage of iron ore to make it from, Australia alone produces tens if not hundreds of millions of tonnes a year) can supply 100,000 tonnes a year meaning that the output of one factory can be used to (assuming the ocean has the capacity) take out of the atmosphere three billion tonnes of carbon.

This is about 50% of global emissions (old figure, I know) from the use of fossil fuels.

For the first time since 1993, global emissions of carbon from the combustion of fossil fuels declined last year, falling 0.5 percent to 6.32 billion tons, according to new estimates by the Worldwatch Institute.

Our 100,000 tonnes will cost us $100 million dollars.

So, two questions that need to be answered.

1) Does this actually work? Does dumping iron powder into nutrient poor areas of the ocean both lead to plankton blooms and if so, how much of the carbon gets locked away, rather than recycled?

2) What is the capacity of the oceans to perform this trick? Is it something we can do with a few hundred tonnes of iron? Or a few hundred thousand?

On the answers to those questions depends really rather a lot. Imagine that it does work, that the ocean potential is large, we could actually suck out of the atmosphere our entire annual output of CO2 for somewhere in the region of a billion dollars.

No, I don't know whether it will work either, but wouldn't it be interesting if it does?

Wouldn't it be really rather delightful if technology really does save us all, rather than the radical restructuring of society that so many seem to be calling for?

OK, to update as Mark called for in comments.

The Planktos expedition is expected to last two years, with repeated monitoring of the 3,860 sq mile drop site, (1,000 sq km) to measure plankton levels and how much carbon they have taken.

That's obviously a horrible typo there, 3.8 thousand sq m is in fact 10,000 sq km (or, it's 1,000 sq km actually being experimented upon and it should be 380 sq m). But we'll take that larger figure.

Global oceans are 360 million sq km and some 70% are thought to be nutrient poor. So, roughly a quarter billion square kilometres could possibly be used.  We're hoping to pull down 3 million tonnes of carbon by using 10,000 km2, which means in theory we can pull down 75,600,000,000 tonnes of C a year. An order of magnitude larger than fossil fuel emissions and still several times greater than total anthropogenic.

So, yes, if it works, it can be done.

May 3, 2007 in Climate Change | Permalink


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I hope someone is doing some scientific research of quality on this because we don't have much of a track record of successfully tinkering with the ecosystem to bend it to our will. What other things are taken out of the oceans? Will it deplete the oceans of vast quantities of nutrients that plankton rely on? Oxygen depletion of the top few metres? What effect will it have on the food chain?

We do have a track record of screwing it up via unintended consequences (a New Labour speciality) such as the introduction of rabbits to Australia.

Posted by: Kay Tie | May 3, 2007 10:13:07 AM

Tim, you sort of broke off the calculations jsut when it was getting interesting.

The total surface area of the ocean is a known figure, I guess that plankton can grow anywhere (including near North and South Poles), the potential total weight of plankton per square mile is a known figure and so on. If the experiment works (and I have no idea how they will prove it one way or another) then surely you can work out the potential total CO2 capture (to within an order of magnitude at least).

As somebody said on an earlier post, all those iron ships that have sunk to the bottom of the sea over the years don't seem to have done any harm.

Posted by: Mark Wadsworth | May 3, 2007 10:26:23 AM

When the whales eat the plankton will they sink as well? Greenpeace will not be happy.

Posted by: Kit | May 3, 2007 11:37:11 AM

What I'm wondering is this: if the experiment is a total success - massive amounts of CO2 are drawn safely into the oceans, new plankton blooms cause massive gains in fish populations, God appears through the clouds with a wink and a tip of his almighty hat to the scientific community, etc. etc - will the environmentalists finally shut up and go back to saving the lesser spotted tern? Something tells me nothing less than a signed and notarised letter from Gaia would convince them that we can fix our problems without moving into yurts and mainlining tofu.

Posted by: sortapundit | May 3, 2007 11:48:03 AM

When I was at school, a long time ago admittedly, we were taught the basic law of physics.

For every action, there is an equal and opposite reaction, although that reaction may not always be immediately apparent.

In short, mother nature has a particular and peculiar way of taking care of herself.
When we (man) start screwing with nature, nature will screw us back.

I am very wary of this 'experiment' and the long term consequences, which we (man) will be in no position to reverse when nature screws us back.

Posted by: IanP | May 3, 2007 12:20:58 PM

Your figures compare dollar costs, which are artificial constructs.

How much CO2 is expended to mine, manufacture, mill and transport the iron powder to its destination ?

Tim adds: Somewhat less than 3 million tonnes C per 100 tonnes Fe would be a safe guess.

Posted by: IanCroydon | May 3, 2007 12:48:14 PM

So the scaremongering eco-worriers think a bloom of oxygen-producing phytoplankton (i.e. microscopic floating plants) might deplete the oxygen in the ocean in spite of being possibly the greatest source of atmospheric oxygen on the planet.

On the subject of the iron used, though. Might not pulverised low-grade iron ore be more suitable, as not only is it cheap, but the "contanimants" making it low-grade are other nutrients (particularly phosphate).

Tim adds: There's an earlier post from a day or two ago looking at using iron ore. Apparently they don't want to use Fe3O4 for some reason that I don't know of.

Posted by: Paul C | May 3, 2007 2:31:37 PM

Cane toads.

Posted by: dearieme | May 3, 2007 2:36:22 PM

Paul C, inspired!

As a complete and utter beginner in these things, it strikes me that the risks associated with using ground-up iron ore, being a natural product, must be much lower (cf. oil spills, nasty to look out but they seem to sort themselves out) and surely the stuff is cheaper (in $ and in CO2 terms) to produce than iron ore powder. Is this any different to when volcanoes in the sea erupt and spew loads of magma/lava (which is high in iron) into the sea?

Posted by: Mark Wadsworth | May 3, 2007 2:44:44 PM

When man decides that it knows better than nature on how to deal with problems of the planet we are on very dodgy ground.

These naturally occurring events of global warming and ice ages have been going on since time began, why are we letting this latest money making fad take over our lives.

What happened to the previous fads, ozone hole, mini ice age and nuclear chain reactions? all backed at the time by so called science. Did the end of world come about? no, mother nature does what she does best, and sorted herself out.

Man at the end of the day is his own worst enemy.

Posted by: IanP | May 3, 2007 3:12:02 PM

When I multiply $85 by 44/12 I get $312, not $100.

Tim adds: Yeah, I know, just couldn't be bothered to do the maths that early in the morning.

Posted by: Paul Zrimsek | May 3, 2007 4:41:49 PM

Idiocy. It's what makes commoners so special. The idea of seeding the ocean to counteract CO2 emissions is like cutting your nose off to spite your face.

OK the economic analysis, though greatly flawed was vaguely interesting. What would be of greater value, however, would be an analysis of whether the goal could actually be achieved, looking at the total inputs and outputs of CO2. Iron doesn't grow on trees, no matter how hard you hug them. You have dig for it. Using machines that burn petroleum and release CO2. It destroys land that might otherwise be biologically productive (i.e., CO2 absorbing). You have to process the ore and transport it, burning yet more fuel and pumping more CO2 into the air. Even if this idea does work and CO2 is absorbed into the ocean, will the overall effect be to RAISE CO2 levels?

Could we devote our energies to solutions instead stupid fantasies?

Tim adds: You did, err, note the points about "experiments"..."if it works"....

Posted by: steve | May 3, 2007 10:10:15 PM

What would be of greater value, however, would be an analysis of whether the goal could actually be achieved, looking at the total inputs and outputs of CO2.

The use of the conditional in this sentence is puzzling; all the snarling which surrounds it seems to presuppose that such an analysis has already been done, with unfavorable result.

Posted by: Paul Zrimsek | May 4, 2007 12:06:54 AM

Buy shipbuilding shares. You'll need 200 times as much SiO2 as iron.

Whoops, we killed the shipbuilders to make Timmeh happy.

Posted by: Alex | May 4, 2007 12:30:11 AM

I can't believe people think we should not mess with the ecosystem. We do it constantly. Pouring and spilling Millions of tons of gases, wastes, chemical, ect into the enviroment. We cover huge areas of land with asphalt and cement and tear down forrests and whatever gets in the way of civilization. But we have other projects that try and restore our environment such as replanting and using alternative clean energy. Iron seeding is not toxic and how it affects our ecosystem is something that needs to be studied. Planktos the ship that will be dumping iron powder will be studying and gathering information for two years. More than likely if the results are positive there will probably be more Government sponsored studies to verify the results befor any massive dumping takes place.

Instead of voicing concerns we should be supportive of what is going on as long as there is reasonable studies that proves this to be safe. Look at what this means to this planet. If every country does everything that the Kyoto Protocal calls for we only delay the global warming. It does not solve the problem only delays it. If the dam is leaking we don't need to sit around talking about "what ifs" because if we don't do something we won't be around to discuss it.

Posted by: dky | Aug 27, 2007 7:34:35 PM

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