Possible cure for global warming found

[SRW]

Previous studies have suggested that during the last four ice ages, the Southern Ocean had large phytoplankton populations and received large amounts of iron-rich dust, which may have been blown out to sea from expanding desert areas. In order to simulate such ice-age conditions, the SOFeX scientists added iron to surface waters in two square patches, each 15 kilometers on a side, so that concentrations of this micronutrient reached about 50 parts per trillion. This concentration, though low by terrestrial standards, represented a 50- to 100-fold increase over ambient conditions, and triggered massive phytoplankton blooms at both locations. These blooms covered thousands of square kilometers, and were visible in satellite images of the area.

Each of these blooms consumed over 30,000 tons of carbon dioxide, an important greenhouse gas. Of particular interest to the scientists was whether this carbon dioxide would be returned to the atmosphere or would sink into deep waters as the phytoplankton died or were consumed by grazers. Observations by Dr. Ken Buesseler of Woods Hole Oceanographic Institution and Dr. Jim Bishop of Lawrence Berkeley National Laboratories (reported separately in the same issue of Science) indicate that much of the carbon sank to hundreds of meters below the surface. When extrapolated over large portions of the Southern Ocean, this finding suggests that iron fertilization could cause billions of tons of carbon to be removed from the atmosphere each year. Removal of this much carbon dioxide from the atmosphere could have helped cool the Earth during ice ages. Similarly, it has been suggested that humans might be able to slow global warming by removing carbon dioxide from the atmosphere through a massive ocean fertilization program.



MBARI

This sound like the beginning of climate manipulation.

 

[davefoc]

To some degree what you report is old news.

If somebody doesn't do it before me, I will provide some links to relevant stories, but this is what I recall from memory.

The possibility of manipulating the climate by increasing phytoplankton populations by spreading iron into the oceans was proposed about five years ago.

There was an initial experiment where the theory that the addition of iron could radically increase phytoplankton growth was confirmed.

Then there another experiment where the theory was tested on a larger scale and once again substantially increased phytoplankton growth was observed.

Finally there was another experiment done where the amount of carbon that actually made it to the ocean floor from the increased phytoplankton population was measured. Unfortunately the results of that experiment were discouraging. It was found that the increased phytoplankton growth also increased the populations of animals that fed on it and thus most of the increase in carbon uptake by the phytoplankton was offset by increased rates of carbon recirculation. That is the carbon was recyled by animals before the carbon could make it to the ocean floor.

There are also environmental concerns with the idea that I have forgotten, but these coupled with experiments that indicated the idea didn't work suggested to me that it was unlikely to be a useful method for global climate control.

 

[EvilYeti]

Finally there was another experiment done where the amount of carbon that actually made it to the ocean floor from the increased phytoplankton population was measured. Unfortunately the results of that experiment were discouraging. It was found that the increased phytoplankton growth also increased the populations of animals that fed on it and thus most of the increase in carbon uptake by the phytoplankton was offset by increased rates of carbon recirculation. That is the carbon was recyled by animals before the carbon could make it to the ocean floor.

There are also environmental concerns with the idea that I have forgotten, but these coupled with experiments that indicated the idea didn't work suggested to me that it was unlikely to be a useful method for global climate control.

Not so fast buddy, when science is involved the devil is in the details.

This is a new experiment, as it focuses on a different part of the ocean then the other experiments (which were coastal, probably due to budget issues).

The research indicates that much of the carbon dioxide was in fact sequestered hundreds of meters below the surface of the ocean. Of course, more work needs to be done, but this is very, very encouraging news!

 

[SRW]

Not so fast buddy, when science is involved the devil is in the details.

This is a new experiment, as it focuses on a different part of the ocean then the other experiments (which were coastal, probably due to budget issues).

The research indicates that much of the carbon dioxide was in fact sequestered hundreds of meters below the surface of the ocean. Of course, more work needs to be done, but this is very, very encouraging news!

Yes what he said, this is not a "new story" it is the result of two decades of research. What is new are the most recent findings. Which are truly remarkable.

 

[Drooper]

It was found that the increased phytoplankton growth also increased the populations of animals that fed on it and thus most of the increase in carbon uptake by the phytoplankton was offset by increased rates of carbon recirculation. That is the carbon was recyled by animals before the carbon could make it to the ocean floor.

Hang. Wouldn't that be one of the mechanisms that would lock away the carbon, in increased biomass? Lots more whales and fish and the like?

 

[EvilYeti]

Hang. Wouldn't that be one of the mechanisms that would lock away the carbon, in increased biomass? Lots more whales and fish and the like?

Google the "carbon cycle". Sure, it locks away the carbon for the lifetime of the mammal, but when it dies and decomposes it just returns right back to atmosphere.

Phytoplankton is different because it will sink to the bottom of the ocean and form limestone deposits. That locks away the carbon for a good long time, at least until the limestone is exposed to air and eroded.

 

[SquishyDave]

Hope this works, then we can all burn fossil fuels as fast we want, and be happy doing it.

Who wants to drive around for a while for no good reason, or leave our gas stoves on all day and night just coz it looks pretty? Lets do it!

 

[Drooper]

Google the "carbon cycle". Sure, it locks away the carbon for the lifetime of the mammal, but when it dies and decomposes it just returns right back to atmosphere.

Phytoplankton is different because it will sink to the bottom of the ocean and form limestone deposits. That locks away the carbon for a good long time, at least until the limestone is exposed to air and eroded.

And the mammal has babies right? If the population if growing it is holding more carbon. If the population is stable it has locked in a constant amount of carbon.

Crikey, this is pretty basic.

 

[EvilYeti]

And the mammal has babies right? If the population if growing it is holding more carbon. If the population is stable it has locked in a constant amount of carbon.

Crikey, this is pretty basic.

Yes, and since old organisms are dying off at similar rates to which new ones are being born the net amount of sequesterd CO₂ remains fairly constant. Unless the population dramatically increased there is no way to keep up with human emissions.

I think you are also underestimating how much carbon is being removed from the atmosphere via mammals, the vast majority of carbon is removed by plant life. You can even see this effect (the carbon cycle) in seasonal trends of CO₂ levels.

See the zig-zag? Thats caused by plants blooming in the spring and absorbing CO₂ followed by the seasonal fall and winter die off, when the carbon is returned to the troposphere. By examing the clear upwards trend its obvious the biosphere is not absorbing the excess CO₂ emitted by human activity.

Again, the only way to reverse the current trend would be to sequester huge amounts (6+ billion tons annually) somewhere its not going to come back anytime soon, like the bottom of the ocean.

 

[Drooper]

Yes, and since old organisms are dying off at similar rates to which new ones are being born the net amount of sequesterd CO₂ remains fairly constant. Unless the population dramatically increased there is no way to keep up with human emissions.

I think you are also underestimating how much carbon is being removed from the atmosphere via mammals, the vast majority of carbon is removed by plant life. You can even see this effect (the carbon cycle) in seasonal trends of CO₂ levels.

See the zig-zag? Thats caused by plants blooming in the spring and absorbing CO₂ followed by the seasonal fall and winter die off, when the carbon is returned to the troposphere. By examing the clear upwards trend its obvious the biosphere is not absorbing the excess CO₂ emitted by human activity.

Again, the only way to reverse the current trend would be to sequester huge amounts (6+ billion tons annually) somewhere its not going to come back anytime soon, like the bottom of the ocean.

Whooaaa there tiger.

I started this little digression pointing out some error in fact. Namely, that an increase in the whale population (say), resulting from increasing the the lowest rung in the marine food chain, would reduce the effectiveness seeding the ocean with iron.

I have no information on what the relative contribution might be, my prior would be that it would be small. However, I am certain I know what the direction of the effect would be.

This is one of the number of problems I have with Global Warming Tub thumpers. Some simple things just don't ring true, and when challenged on them, they obfuscate by employing either irrelevant data and arguments, or by unecessarily complicating the whole issue.