Experiment: Lower CO2 by Stimluating Plankton Growth

[On the Road]

Robotic Floats Shed New Light On Iron Hypothesis

The iron hypothesis holds that by adding small amounts of iron, an essential micronutrient, to ocean waters rich in other nutrients, aquatic plants can be made to bloom vigorously, thus removing enough carbon dioxide from the atmosphere to offset the greenhouse effect.

----snip

A pair of robotic Carbon Explorers recorded and regularly reported, via satellite, more than a four-fold growth of plankton in a fertilized patch of nitrate-rich but silicate-poor waters, measurements that contradicted the expectation that lack of dissolved silicates would limit plankton growth.

Programmed to descend to depths of up to one kilometer several times a day, the floats measured concentrations of particulate organic carbon and documented its export, within and outside the fertilized area, below 100 meters. They showed that for every atom of iron added to the water, the plankton carried between 10,000 and 100,000 atoms of fixed carbon below 100 meters upon sinking, well beneath the zone of light-stimulated plant growth.

----snip

However, the Carbon Explorer results strongly support the third alternative: "The only way iron fertilization can have an impact on atmospheric carbon is if the plants fix the carbon, and a major fraction of that carbon settles out of the surface layer into the deep sea"--either as waste from grazing zooplankton or other aggregate particles, or as the plants themselves sink.

----snip

http://www.sciencedaily.com/releases/2004/04/040416015016.htm

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Who knows -- It's one wasy to reduce atmospheric carbon.

[mstrsplinter326]

1. solutions?

I read somewhere the other day that the expectations of the experement were never reached and that it was improbable that this was even a feesable temporary solution. But I don't profess to know much about the whole deal.

[On the Road]

3. I Had Just Read an Article in "Wired" a Couple of Years Ago

It proposed that a fleet of ten barges continually seeding the Indian Ocean with Iron could remove most of the additional carbon being put into the atmosphere. Looks like someone is seriously pursuing the idea.

[havocmom]

2. Plant trees

Lots and lots of trees. They also help with the CO2 ratio and enough of them in an area start to make a difference for humidity/rainfall, which is a serious problem for many places.

Cutting down massive forests to make way for corporate agruculter is just not good for the planet. We need the oceans and the trees to do their part.

[k in IA]

4. Serve lots of crabby pattys to the Plankton - they love that

[treepig]

5. uh oh

Study rules out iron-seeding to fight warming

A once-promising theory that seeding oceans with iron to create plankton blooms to extract greenhouse gases from the atmosphere has turned out to be impractical in the long term, a study released says.

A study led by New Zealand's University of Otago of Dunedin found that while a ton of iron would fertilise a phytoplankton bloom, it would also require at least 5,000 tons of silicate to sustain it.

"It's just not practical," Otago oceanographer Philip Boyd said in a paper published in the science journal Nature and issued on Friday by the university.

http://www.abc.net.au/news/newsitems/s1069534.htm

perhaps the wrong approach?

Iron from below, not above

In the cold Southern Ocean, the short supply of dissolved iron limits plant life. The late John Martin proposed in 1990 that dust delivered iron to the Southern Ocean during glacial intervals, creating an increase in productivity. This so-called “Iron Hypothesis” had far-reaching effects for both geoscientists and policy-makers. Increasing productivity in the Southern Ocean could draw more carbon dioxide out of the atmosphere, creating a large carbon sink.

For the past decade, scientists have used this hypothesis as fuel for experiments to fertilize the Southern Ocean with iron, but so far have found only temporary effects. Now, two researchers say they know why these experiments have failed. They offer an alternative source for glacial iron in the Southern Ocean.

http://www.geotimes.org/mar02/NN_iron.html

[Viking12]

6. Good find treepig

This and other geo-engineering schemes only prolong the reality that we are going to have to change the way we live if we want to mitigate climte change. Most have been shown to be extremely limited in their potential impact on conentrations of CO2 ot they'bve been shown to creat another set of equally undesirable effects.

[Nihil]

7. Even if the silicate requirement wasn't so high ...

... I can't see how it would be other than a temporary solution?

Surely the iron/bloom process is just another temporary store rather
than a permanent sink?

Wouldn't that mean that as the C gradually cycles back into the
atmosphere after a time, the resultant loading would be significantly
non-linear?

(Asking from a position of ignorance - separated in distance from my
books and in time from my studies - so please be gentle! :-))

[On the Road]

8. One Thing They Were Testing

is whether the plankton take the carbon to the ocean floor when it dies. That would be pretty long-lived storage.

I've saw another proposal in Wired for gathering up crop waste in cornfields every year and dumping it into the deep ocean. Removes a surprisingly large amount of carbon.

There will have to be multiple ways to attack this problem. Energy prices and technical advances will eventually mean less carbon being introduced into the environment, but even if the level stays the same the existing carbon will still continue heating the earth.