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One of the main "protests" from scientists (like myself) is not that this doesn't sequester carbon. But by sopping up macronutrients (nitrogen in particular) t

One of the main "protests" from scientists (like myself) is not that this doesn't sequester carbon. But by sopping up macronutrients (nitrogen in particular) to form large diatoms, you greatly disadvantage smaller, floating plankton that stay afloat and actually feed the marine food web. Note: I'm not against the actual small-scale experiments. We may someday have to choose between sequestration and whales. Just pointing out that the objections to large-scale use aren't as silly and reactionary as the article makes them out to be.

jobu 12y ago
There was an experiment in 2009 that ended up seeding algae and plankton instead of diatoms, but it didn't sequester carbon as hoped: http://www.awi.de/en/news/press_releases/detail/item/lohafex_provides_new_insights_on_plankton_ecology_only_small_amounts_of_atmospheric_carbon_dioxide/?tx_list_pi1%5Bmode%5D=6&cHash=ffd0b4deee http://www.awi.de/en/news/press_releases/detail/item/lohafex... It seems the larger diatoms seeded in the more recent experiment may actually be better at sequestering carbon. We need to be doing more experiments like this so we understand the processes and potential fallout before we get to a point where our survival depends on it succeeding.
- JulianMorrison 12y ago
  Anything that builds carbonate skeletons sounds eminently sensible - unlike edible plant matter, those probably won't just be breathed back out by whatever eats them.
revscat 12y ago
I am not a scientist, but this objection seems rather short-sighted. The threat posed by global warming is to the ecosystem as a whole. If the smaller-scale (but still large) systems are negatively affected, but the system as a whole is saved, then this would be a worthwhile effort.
- squidfood 12y ago
  Well, that's a societal choice. So's keeping the fishing grounds open. The main point is that fertilization is a tradeoff, not a free lunch.
- deleted 12y ago
  [deleted]
- whyenot 12y ago
  I am a scientist (a botanist) and I don't think the objection is short sighted. You are fundamentally changing the base of the marine food web. This is not a system that is well understood, and one that is difficult to model. This type of intervention might be successful, but you could also kill off large amounts of marine life, making a bad situation significantly worse. That doesn't mean geoengineering shouldn't be explored, but it's potentially risky. A wrong move could lead to mass starvation of not only marine life, but the numerous human populations that depend on that marine life.
ScottBurson 12y ago
I think there are some valid concerns. But I think there is also a certain amount of reaction, in some circles, against the idea that we should be able to hack our way out of global warming without actually reducing our carbon emissions. I'm all for reducing carbon emissions as fast as we reasonably can, but it takes time. I don't think we should reject geoengineering out of hand, at least as a stopgap. Whether it becomes something that we wind up doing hundreds of years into the future, and what the costs of that will be if we do, remain to be seen. I'm actually surprised we haven't started experimenting with adding sulfur to jet fuel. Nature puts sulfur in the stratosphere itself on occasion, so we have a pretty good idea that it works. The half-life is on the order of a few months, so if we overdo it a bit, all we have to do is stop. I saw a long list of objections to the use of sulfur aerosols, and the only one that seemed strong to me was that it doesn't help at all with ocean acidification. Well, okay; but iron fertilization would work for that. Maybe using these (and possibly other) techniques in concert would mitigate the downside that each would have if you tried to solve the whole problem with it.
- gizmo686 12y ago
  Assuming we can stop carbon emissions completely today, we should not reject engineering out of hand. By definition, the emmisions effect the rate of change of carbon concentration, but what we care about from a climate perspective is the concentration itself.

jobu 12y ago

There was an experiment in 2009 that ended up seeding algae and plankton instead of diatoms, but it didn't sequester carbon as hoped: http://www.awi.de/en/news/press_releases/detail/item/lohafex_provides_new_insights_on_plankton_ecology_only_small_amounts_of_atmospheric_carbon_dioxide/?tx_list_pi1%5Bmode%5D=6&cHash=ffd0b4deee http://www.awi.de/en/news/press_releases/detail/item/lohafex... It seems the larger diatoms seeded in the more recent experiment may actually be better at sequestering carbon. We need to be doing more experiments like this so we understand the processes and potential fallout before we get to a point where our survival depends on it succeeding.

JulianMorrison 12y ago
Anything that builds carbonate skeletons sounds eminently sensible - unlike edible plant matter, those probably won't just be breathed back out by whatever eats them.

revscat 12y ago

I am not a scientist, but this objection seems rather short-sighted. The threat posed by global warming is to the ecosystem as a whole. If the smaller-scale (but still large) systems are negatively affected, but the system as a whole is saved, then this would be a worthwhile effort.

squidfood 12y ago
Well, that's a societal choice. So's keeping the fishing grounds open. The main point is that fertilization is a tradeoff, not a free lunch.
deleted 12y ago
[deleted]
whyenot 12y ago
I am a scientist (a botanist) and I don't think the objection is short sighted. You are fundamentally changing the base of the marine food web. This is not a system that is well understood, and one that is difficult to model. This type of intervention might be successful, but you could also kill off large amounts of marine life, making a bad situation significantly worse. That doesn't mean geoengineering shouldn't be explored, but it's potentially risky. A wrong move could lead to mass starvation of not only marine life, but the numerous human populations that depend on that marine life.

ScottBurson 12y ago

I think there are some valid concerns. But I think there is also a certain amount of reaction, in some circles, against the idea that we should be able to hack our way out of global warming without actually reducing our carbon emissions. I'm all for reducing carbon emissions as fast as we reasonably can, but it takes time. I don't think we should reject geoengineering out of hand, at least as a stopgap. Whether it becomes something that we wind up doing hundreds of years into the future, and what the costs of that will be if we do, remain to be seen. I'm actually surprised we haven't started experimenting with adding sulfur to jet fuel. Nature puts sulfur in the stratosphere itself on occasion, so we have a pretty good idea that it works. The half-life is on the order of a few months, so if we overdo it a bit, all we have to do is stop. I saw a long list of objections to the use of sulfur aerosols, and the only one that seemed strong to me was that it doesn't help at all with ocean acidification. Well, okay; but iron fertilization would work for that. Maybe using these (and possibly other) techniques in concert would mitigate the downside that each would have if you tried to solve the whole problem with it.

gizmo686 12y ago
Assuming we can stop carbon emissions completely today, we should not reject engineering out of hand. By definition, the emmisions effect the rate of change of carbon concentration, but what we care about from a climate perspective is the concentration itself.