Geoengineering with iron might work after all

Editorial: “We can’t afford to neglect ways to halt global warming”

IF YOU want to help stop climate change, try tipping some iron into the sea. For years, this geoengineering idea has been considered a busted flush, but new results suggest it really can work.

Tiny floating algae called phytoplankton pull carbon dioxide out of the atmosphere. When they die, the plankton sink to the seabed, taking the carbon with them. Over thousands of years, this strips CO2 from the air, lowering temperatures.

But many ocean regions are short of iron, which plankton need to grow, so the process does not occur. Adding iron should stimulate plankton growth in these areas.

That was the theory, at least. In practice, it is charitable to say the results have been mixed. For many people, the idea died in 2009, when a field trial called Lohafex failed in the South Atlantic. The iron triggered a bloom, but it was eaten by crustaceans before it could sink.

However, another trial, called Eifex, was carried out in the Southern Ocean in 2004. The results have finally been published – and they are promising. The Eifex ship found an ideal testing ground: a slowly rotating eddy 60 kilometres across and 4 kilometres deep, which was more or less isolated from the surrounding waters.

Victor Smetacek of the Alfred Wegener Institute for Polar and Marine Research in Bremerhaven, Germany, and colleagues dumped iron sulphate into the eddy’s core and studied the resulting bloom.

The water was rich in silicic acid, so the bloom was dominated by phytoplankton called diatoms. These algae build silica cell walls, which makes them harder to eat and more likely to sink than plankton with calcium carbonate shells. “They are not the pastures of the ocean, they are the thistles,” Smetacek says.

The diatom bloom grew for three weeks, then died and sank. At least half of it sank far below 1 kilometre, and probably reached the sea floor (Nature, DOI: 10.1038/nature11229).

No other study has tracked a sinking bloom. “This confirms what we expected to happen,” says Richard Lampitt of the UK’s National Oceanography Centre in Southampton, who was not involved in the study. Lampitt says Lohafex failed because the trial site was low in silicon, so the bloom contained few diatoms.

Eifex’s success is far from a green light for iron fertilisation, though. At most, a global programme could mop up about 1 gigatonne of carbon per year, about a tenth of our current emissions, according to a modelling study by Ken Caldeira at the Carnegie Institution of Washington in Stanford, California (Climatic Change, DOI: 10.1007/s10584-010-9799-4). “It’s too little to be the solution,” agrees Smetacek, “but it’s too much to ignore.”

Fertilised patches create algal food sources but burn through ocean nutrients. This could be a boon to some threads of the food web (see “Iron fertilisation and the whales”), but it could suppress diatom formation elsewhere to the detriment of other marine species.

All those contacted by New Scientist agreed that any tests should be run as a public good, not for profit. Some firms had planned to use iron fertilisation to accrue carbon credits which they could sell on, but in 2008 the London Convention and Protocol – an international treaty – ruled that the practice should not be allowed.

Iron fertilisation and the whales

Iron fertilisation is mainly seen as a way to engineer the climate (main story), but it could also help boost whale populations by restoring their natural ecosystem, says Victor Smetacek of the Alfred Wegener Institute for Polar and Marine Research in Bremerhaven, Germany.

Many Southern-Ocean whales feed on Antarctic krill (Euphausia superba). This krill is one of the few species that eat algae called diatoms in large quantities, but krill numbers have been plummeting for decades.

Increasingly, ecologists suspect that declining krill numbers are linked to humanity’s over-hunting of whales. Whale faeces are rich in the iron that helps fuel diatom growth. This in turn benefits the krill – and ultimately the whales. “Whales might be effectively fertilising their own foods, and a reduction in whale populations would impact on that food resource,” says David Raubenheimer of Massey University in Auckland, New Zealand.

There is no guarantee that the boosted diatoms would end up being eaten by krill, though, or that the resulting increased krill would be eaten by whales.

“There are many other competitors in the ecosystem,” notes Ian Boyd at the University of St Andrews in the UK.


Issue 2874 of New Scientist magazine


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Comments

Thu Jul 19 15:01:19 BST 2012 by Eric Kvaalen

One thing that should be checked is whether the plankta that sink have more organic carbon than inorganic (that is, carbonate in those that have calcite shells). When a bicarbonate ion is incorporated into a carbonate shell, another bicarbonate ion has to turn into carbon dioxide, which makes global warming worse.

The idea that there is less krill because there are fewer whales doesn’t make sense. The whales may contribute iron to the sea in their faeces, but they got that iron from the sea in the first place. Putting whales into the system would not increase the concentration of iron.

I don’t see what’s wrong with companies seeding the ocean with iron for profit, if it really is a good thing to do. If companies don’t do it for profit, then who’s going to do it? The EPA? Isn’t it better to have competition to increase efficiency?

Comments

Thu Jul 19 19:57:50 BST 2012 by Liza

“Putting whales into the system would not increase the concentration of iron.”

Whales would not change the total amount of iron going around, but they may redistribute the iron available to spots more accessible for plankton and therefore krill.

“I don’t see what’s wrong with companies seeding the ocean with iron for profit, if it really is a good thing to do.”

Because what’s profitable and what’s a good thing to do is often incompatible! Besides, administrations supposed to make “good things to do” profitable for private companies through subsidies (a roundabout way of redistributing money from public to to private ownership), often get converted into money-consuming bureaucracies with plenty of loopholes for those wishing to make money without caring about what might be a good thing to do!

Comments

Fri Jul 20 04:34:35 BST 2012 by Jamie W.

PS

For a wonderfully vivid and terrifying piece of speculative fiction that speaks volumes about these issues, I highly recommend The Windup Girl by Paolo Bacigalupi. An amazing book, character-driven sci-fi of the highest order.

Comments

Fri Jul 20 04:28:46 BST 2012 by Jamie W.

Sawasdee khap my friends, I’m posting from beautiful Bangkok, the real City of Angels. I’ve been missing y’all.

To the matter at hand:

“If companies don’t do it for profit, then who’s going to do it? The EPA? Isn’t it better to have competition to increase efficiency?”

Correct me if I’m wrong, but isn’t this whole steaming mess we’re in entirely due to the continual drive for increasing profits? I find it appalling that geo-engineering of any kind is even being countenanced, given our massively limited understanding of the systems involved.

The free market is damaging the global ecosystem, perhaps irrepairably, yet we’re seriously considering allowing the monster to fiddle with global bio-chemistry to save its own behind. Sounds like madness to me…

Comments

Fri Jul 20 10:04:24 BST 2012 by Liza

You’re in Thailand and still bothered to check the NS site? Crazy b*gger!

Anyway, nice hearing from you too, Jamie. I was already wondering where you’d disappeared to 🙂

Comments

Fri Jul 20 13:00:24 BST 2012 by Sandy Henderson

Hi Jamie – I note that you, like many others are a bit “free” with the word free. Describing something as free implies either at liberty, or unregulated. The former usually accepts responsibility for how that freedom is used, whilst the latter is licence to act without the burden of the consequences. Unfortunately that appears to be what has been happening for a very long time now and those who actively seek power and / or influence have been just as assiduous at finding ways to evade the responsibility which in natural systems punishes excess, albeit on a varying time scale. We know the corrupting ability of power, even at trivial levels, yet do little to combat it with checks and balances, previously seen as necessary after affairs got out of hand for more or less the same reason. Nature motivates behaviour with a combination of “carrot and stick” and neither is successful on it’s own. I find that my sheep learn to do more elaborate things that are rewarded, than if they are only avoiding pain. In many ways sheep are about as smart as people in the things that matter to them

Comments

Fri Jul 20 05:53:36 BST 2012 by Eric Kvaalen

I’ll reply here to both Liza and Jamie.

Liza, the whales take their iron from the place where the plankta are, because that’s where the krill are also. So they’re taking and giving iron to the same chunk of water.

Liza, spreading iron in the ocean is not profitable! (That’s why nobody is doing it.) It would only be profitable if governments decided to make it profitable, for instance by implementing a cap-and-trade system and allowing companies to get carbon credits by doing this.

I don’t see why letting private companies do it would involve more bureaucracy than governments doing it themselves.

As I said, this should only be made profitable if it really is a good thing to do!

Jamie, this whole steaming mess we’re in is due to people heating their homes with fossil fuel, using electricity made with fossil fuel, driving using fossil fuel, and taking planes that use fossil fuel.

So you’re in Thailand! How did you get there?

I saw a documentary recently that had a part on Thailand and the sex trade. A woman said she asked a prostitute whether she wasn’t worried by the spate of murders. She answered that she’s not afraid of that because dying and going to hell would be better than her life.

Comments

Fri Jul 20 09:08:20 BST 2012 by Liza

“they’re taking and giving iron to the same chunk of water.”

True, which means the whales are keeping the iron where it’s needed. What would happen to the iron-containing krill if not eaten by whales? Option 1. they are eaten by something else. We need to know who’s eating them and where they deposit their faeces and whether those faeces contain the iron in an equally accessible configuration as whales’. If the krill gets eaten by seabirds for example, some of the iron would end up in guano on islands. Option 2. No other animal is capable of eating the same amount of krill as whales do. The krill just dies of old age and sinks to the bottom or is decomposed in situ. If the first, iron is lost to the surface waters. If the second, the iron may be in a less accessible state compared to after digestion by whales.

Jamie probably took a boat or a plane. If not, he must be a really good swimmer 🙂

The sex trade is a disgrace for humankind. I object to it’s being called a trade btw. It’s more like organised perpetual rape.

PS: I saw Karl didn’t react on your post…I’m sorry!

Comments

Fri Jul 20 21:07:25 BST 2012 by Eric Kvaalen

But let’s say that the whales have been gone for many years. So the system should have reached a sort of steady state. If the iron gets taken away by seagulls or sinks to the bottom of the sea, then there wouldn’t be much there now — which is actually the case. So adding a bunch of whales won’t bring the iron back — unless maybe they bring it from other parts of the ocean.

Maybe Karl hasn’t seen my post.

Comments

Fri Jul 20 09:56:36 BST 2012 by Liza

I kept politics for a separate post 🙂

“I don’t see why letting private companies do it would involve more bureaucracy than governments doing it themselves.” Really? You need at least one extra organisational level, probably 2. Each extra link in the chain of action obviously entails extra bureaucracy plus more opportunities for corruption.

Also, companies are after profit. It will be in their interest to lobby for the subsidies to continue even if it turns out not a good thing to do after all. Governments have no such conflict of interests. If it turns out to be a bad idea, they have no reason not to stop immediately.

“Jamie, this whole steaming mess we’re in is due to people heating their homes with fossil fuel, using electricity made with fossil fuel, driving using fossil fuel, and taking planes that use fossil fuel.”

You’re exaggerating the freedom of action of individuals. Unchecked capitalism can only lead to a well-functioning society if you assume all people to be perfectly informed and willing to put public interest first. Both assumptions are false.

Naomi Klein in her book The Shock Doctrine has some interesting things to say on what happens if you privatise what should be core government functions, such as the army, and on some of the contributing factors of the Thai sex industry. I hesitated to buy the book at first because she’s a known political activist, and I’m more interested in data than opinion, but she did some deep digging and knows her facts well.

Comments

Fri Jul 20 21:17:05 BST 2012 by Eric Kvaalen

A lot of people would disagree with you on whether or not government people have no such conflicts of interest. Bureaucrats like to keep their jobs too.

On energy use, you want to exonerate the public, which uses the energy, and blame the capitalist system. Let me tell you, when I was in Russia, the woman I stayed with would leave her gas stove on (in the summer). The gas was paid for by the government, but buying matches would be on her account! (She was a famous former actress but barely surviving.)

And Jamie blames the companies that sell him jet air trips.

Comments

Fri Jul 20 13:03:45 BST 2012 by Jamie W.

Liza, I’ve just spent a week on an island off the coast of Cambodia which has no ‘net access or even telephones and only four hours of diesel generated power per day, so I was jonesing for a little technology. Although the midnight swimming in crystal clear water blazing with phosphorescent microorganisms did satisfy my appetite for wonder…And as I said, I’ve been missing you!

Eric (I’ve been missing you too), I flew to Thailand and have been traveling throughout Thailand and Cambodia by train, bus, and tuk-tuk.

If I had a choice I’d be traveling via , I don’t know, solar-charged railgun-launched glider or something, but I don’t have a choice, do I? The choice has been made for me by rampant profiteers. In the late 90s the US military consumed the equivalent of NASA’s annual budget every three days – imagine the materials, propulsion and power-generation technology we’d be using today if those funding allocations were reversed; if the money that was used to produce something as obscene as a stealth-bomber with a white-phosphorous payload had been used to develop cleaner power sources. As Westinghouse said to Tesla, if it can’t be metered and sold it ‘aint getting built.

Blaming the addict and exonerating the pusher is a pretty weak argument if you ask me.

I’m not sure why you’re mentioning the misery of Thai prostitutes. Do you think they’re more miserable than French, German or American ones? My sweetheart and I certainly won’t be going anywhere near Pat Pong. We’re here for the people, the food, and the glorious feeling of heart-pounding vivacity that seems to exist only in this part of the world. Also, Angkor Wat. Wow

Comments

Fri Jul 20 15:53:21 BST 2012 by Liza

Such a pity the NS site doesn’t allow us to upload holiday pics 🙂

I guess the misery of prostitutes is directly proportional to the amount of force (physical or economical) that pushed them into the profession…

Comments

Fri Jul 20 20:59:04 BST 2012 by Eric Kvaalen

A solar-charged railgun-launched glider wouldn’t work, but you could have taken a boat! No rampant profiteer forced you to fly. You’re just like all the other consumers of the world.

By the way, in the late 90’s NASA’s budget was around $14 milliard a year. According to you, that would put the military at $1700 milliard a year. That was the size of the whole US budget. So don’t believe everything you hear.

What do you mean by the addict and the pusher? You’re the addict and the oil companies who let you fly in jets are the pushers?

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