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Seaweed could be scrubbing more carbon from the atmosphere than expected (2017)

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31–40 of 166 posts

Re: Seaweed could be scrubbing more carbon from the atmosphere than expected (2017)

#31
post #6

Earlier quoted context omitted.

We know that there are a number of homeostatic (self-regulating) processes that affect the proportion of CO2 in the atmosphere; if it wasn't homeostatic it would have drifted off to an extreme long ago. The key question is how well and how rapidly these mechanisms can respond to an increase in CO2 levels.

The homeostasis might work in a limited range under which the biological world evolved in the recent past. Exceeding that range could quickly turn to a runaway geological event of rapid climate change, a state transition in a complex and unpredictable system. Take for example the great oxidation event happening 2.5 billion years ago. As oxygen excreting algae began to take over methane producing organisms, oxygen sta…

> So I have full faith life on Earth will eventually restore the feedback loops and get the temperatures back in the sweet spot.

Or just broadly adapt to the new state of things, historical data suggests that atmospheric CO2 levels did reach ~1000PPM up to the Cretaceous, with complete lack of continental ice sheets and temperate forests at the poles.

The current sweet spot is a sweet spot for us and the ecosystems we grew up in as a species, it's not a life-wide sweet spot.

Re: Seaweed could be scrubbing more carbon from the atmosphere than expected (2017)

#32
Most of what I've read lately seems to indicate climate change can't be mitigated through societal restraint at this point. I think we need to seriously approach an engineered solution akin to terraforming. I'd love to know what efforts are being made in this direction.

Re: Seaweed could be scrubbing more carbon from the atmosphere than expected (2017)

#33
post #24

Also relevant: Feeding dairy cows seaweed mitigates the amount of methane they pass. Irish famers are beginning to do this because seaweed is easy to come by in Ireland. https://phys.org/news/2018-05-seaweed-relieve-gassy-cows-dai...

This would be a great win-win! But wouldn't the sequestered CO2 get released back into the environment and potentially the atmosphere?

Re: Seaweed could be scrubbing more carbon from the atmosphere than expected (2017)

#34
post #9

Really interesting. Makes me think of Daisyworld and the Gaia Hypothesis. Daisyworld is a model Earth covered in black and white daisies, that either absorb or reflect light. In the model, black daisies need less light because they absorb more, increasing the Earth's heat absorption. White daisies absorb less so need more light, but also reflect more light back, increasing the surface albedo of the planet and lowerin…

> Because of this, there's a feedback loop were even if the sun gets a little hotter or colder, the successful daisy would spread and either warm or cool the Earth in response, effectively acting as a stabilizer. Gaia theory suggests that the world is full of these stabilizing systems. There are several mechanisms in place on earth to stabilize changes in atmospheric composition and temperature (otherwise an sporadic…

What specific baseline do you pick, and why? are there multiple variables involved in that "baseline"? have these variables changed over the 10k years preceding the Industrial Revolution? together or separately? what about these same variables over the last 200k years?

Re: Seaweed could be scrubbing more carbon from the atmosphere than expected (2017)

#35
post #30

Stupid question incoming. Does it really help us to trap even more CO2 under the surface? If something exposes that CO2 again, it will be back up in the atmosphere right? So it feels like this would be a "solution" like storing used uranium underground in lead containers - eventually it will become a problem. Or am I completely wrong here?

I don’t think it can truly use seaweed to sequester carbon unless we harvest the seaweed and entomb it underground - but it has to be somewhere the decomposition won’t leak carbon into the atmosphere.

The (early) findings of the study is that is sequestered from leaking into the atmosphere. From the article: "The study estimated that about 11 percent of total seaweed production may be sequestered, most of it after it sinks down into the deep sea."

Re: Seaweed could be scrubbing more carbon from the atmosphere than expected (2017)

#36

Earlier quoted context omitted.

The homeostasis might work in a limited range under which the biological world evolved in the recent past. Exceeding that range could quickly turn to a runaway geological event of rapid climate change, a state transition in a complex and unpredictable system. Take for example the great oxidation event happening 2.5 billion years ago. As oxygen excreting algae began to take over methane producing organisms, oxygen sta…

> So I have full faith life on Earth will eventually restore the feedback loops and get the temperatures back in the sweet spot. Or just broadly adapt to the new state of things, historical data suggests that atmospheric CO2 levels did reach ~1000PPM up to the Cretaceous, with complete lack of continental ice sheets and temperate forests at the poles. The current sweet spot is a sweet spot for us and the ecosystems w…

The Return to Cretaceous World” just doesn’t have the same cinematic draw to it.

Re: Seaweed could be scrubbing more carbon from the atmosphere than expected (2017)

#37
post #27

Does this mean that, like barbecue, it should be eaten in moderation because of cancer risks?

LOL!

Sure buddy! Remember: carbon = bad for you

I for one, follow a strictly carbon-free diet and am as healthy as ever!

Re: Seaweed could be scrubbing more carbon from the atmosphere than expected (2017)

#38
post #33
post #24

Also relevant: Feeding dairy cows seaweed mitigates the amount of methane they pass. Irish famers are beginning to do this because seaweed is easy to come by in Ireland. https://phys.org/news/2018-05-seaweed-relieve-gassy-cows-dai...

This would be a great win-win! But wouldn't the sequestered CO2 get released back into the environment and potentially the atmosphere?

Methane is a stronger greenhouse gas than CO2.

Re: Seaweed could be scrubbing more carbon from the atmosphere than expected (2017)

#39

Stupid question incoming. Does it really help us to trap even more CO2 under the surface? If something exposes that CO2 again, it will be back up in the atmosphere right? So it feels like this would be a "solution" like storing used uranium underground in lead containers - eventually it will become a problem. Or am I completely wrong here?

Storing used uranium is actually pretty effective in the long term. The other byproducts wear themselves out, and the uranium itself is semi-safe.

Re: Seaweed could be scrubbing more carbon from the atmosphere than expected (2017)

#40
post #6

Earlier quoted context omitted.

We know that there are a number of homeostatic (self-regulating) processes that affect the proportion of CO2 in the atmosphere; if it wasn't homeostatic it would have drifted off to an extreme long ago. The key question is how well and how rapidly these mechanisms can respond to an increase in CO2 levels.

The homeostasis might work in a limited range under which the biological world evolved in the recent past. Exceeding that range could quickly turn to a runaway geological event of rapid climate change, a state transition in a complex and unpredictable system. Take for example the great oxidation event happening 2.5 billion years ago. As oxygen excreting algae began to take over methane producing organisms, oxygen sta…

> I have less faith that this will happen soon, or that most species, humans included, can survive such a massive transition event.

This stuff doesn't happen in a year. And we have a bunch of ways of ego-engineering, what's missing is an acute need and the economics/political incentives, which again, an acute need would provide.

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