Plan to Slow Global Warming By Dumping Iron Sulphate into Oceans

ananyo writes "In the search for methods of geoengineering to limit global warming, it seems that stimulating the growth of algae in the oceans might be an efficient way of removing excess carbon dioxide from the atmosphere after all. Despite attracting controversy and a UN moratorium, as well as previous studies suggesting that this approach was ineffective, a recent analysis of an ocean-fertilization experiment eight years ago in the Southern Ocean indicates that encouraging algal blooms to grow can soak up carbon that is then deposited in the deep ocean as the algae die. Each atom of added iron pulled at least 13,000 atoms of carbon out of the atmosphere by encouraging algal growth which, through photosynthesis, captures carbon. The team reports that much of the captured carbon was transported to the deep ocean, where it will remain sequestered for centuries — a 'carbon sink' (abstract)."

Re:Ending badly?

[ShanghaiBill]

.. maybe we can just set fire to the algae if it gets out of control...

Or we can try this on a trial basis, and scale it up if it seems to be working. When the algae sinks, carrying the carbon to the bottom of the ocean, it takes the iron with it. So when we stop putting the iron in, the amount of algae returns to normal, so it is unlikely to "get out of control." Sure, there might be some side effects, but there will probably be even bigger side effects if we do nothing. And the side effects are not all bad: it should increase the amount of fish that can be sustainably harvested.

Re:Ending badly?

[aXis100]

It's not a new thing - iron dust has been blowing into the oceans for millenia.

Recent urban development around our coastlines have significantly reduced this natural nutrient source, so projects like this are really just restoring balance.

Re:Ending badly?

[phantomfive]

The underlying problem is, people are willing to consider anything - except addressing the cause of the problem.

The underlying problem is too hard to solve with current technology. According to Hansen et al, we need to get the CO2 levels down to 350ppm if we want to be safe. This means, not only must we immediately stop adding CO2 to the atmosphere, we also need to remove some of it.

So think of all the things you do that add CO2 to the atmosphere (of course breathing doesn't count because it is net neutral). That is pretty near everything. Imagine if we stopped all that immediately. Not only would we have to switch over to nuclear, we'd also have to stop driving. And flying. Good luck at that, it would be economic suicide.

No one is willing to do that, so the only proposals are things like Kyoto, which did little, or Copenhagen, which would have done nothing.

Re:Just as sure

[Anonymous Coward]

It was good up until that part where people "enjoy high speed". It is more that they don't want to slow down because they are being chased by something possibly deadly.

This is so common it is like a meme. You have arbitrarily set the cost of global warming to infinity, and the cost of "fixing it" near zero, thus leading to a useless cost-benefit analysis. Meanwhile you think you are more informed and intelligent than the "deniers". Read the IPCC AR4, they do a pretty good one.

Re:Just as sure

[SuricouRaven]

"What is this deadly thing that is chasing humanity and necessitates the environmental destruction of the past 100-150 years?"

A return to those hellish days when people had to repair broken things rather then throwing out and buying new, and not everyone could afford to take a holiday on another continant?

Re:Just as sure

[khipu]

It is a risk management issue. We know there is a risk of global warming. We know it can potentially bring massive (earth altering amounts) losses if unmitigated.

According to the IPCC report, the losses are not "massive", they amount to a few percent of global GDP, comparable to how much it would cost to mitigation. The losses for the US and Europe are even smaller.

Global warming is something we can live with: it causes changes, will impose some costs, but it is not a civilization killer. (Global cooling, on the other hand, is a huge problem. The US and Europe would be in deep trouble if climate went back to the way it was a few thousand years ago.) And carbon emissions will abate over the next couple of decades anyway, as solar and other technologies become more attractive and cheaper.

The question is do we wait uninsured, or do we consider an insurance policy of some sort.

I'm pretty sure dumping massive quantities of iron into the ocean and causing algal blooms is not "insurance", it is pollution.

Re:Ending badly?

[khipu]

The underlying problem is too hard to solve with current technology. According to Hansen et al, we need to get the CO2 levels down to 350ppm if we want to be safe. This means, not only must we immediately stop adding CO2 to the atmosphere, we also need to remove some of it.

Hansen is someone who spreads FUD to gain notoriety. Read the IPCC instead. It contains a lot of scary imagery too, but ultimately, you can find a simple cost/benefit analysis, which sums it up:

http://www.ipcc.ch/publications_and_data/ar4/syr/en/mains5-7.html [www.ipcc.ch]

For increases in global average temperature of less than 1 to 3ÂC above 1980-1999 levels, some impacts are projected to produce market benefits in some places and sectors while, at the same time, imposing costs in other places and sectors. Global mean losses could be 1 to 5% of GDP for 4ÂC of warming, but regional losses could be substantially higher.

Limited and early analytical results from integrated analyses of the global costs and benefits of mitigation indicate that these are broadly comparable in magnitude, but do not as yet permit an unambiguous determination of an emissions pathway or stabilisation level where benefits exceed costs.

The idea that we should dump vast quantities of iron into the ocean in order to mitigate a potential problem that amounts to little more a slight reduction in global GDP is ludicrous. Algal blooms and tinkering with iron content of the ocean is far more dangerous than rising CO2 levels, Hansen's cataclysmic fantasies notwithstanding.

Re:Just as sure

[Kell Bengal]

This always confuses me. Why do people seem to think that climate scientists advocate deindustrialisation? I have never heard a serious case arguing for it. And yet, many arguments against global warming measures seem to claim that that is what is being proposed. Wherefore this misconception?