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Could seaweed be the 'fastest and least expensive' tool to fight climate change?

nationalgeographic.com

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Re: Could seaweed be the 'fastest and least expensive' tool to fight climate change?

#151

Post by rjtc »

analog31 wrote: post #63
rjtc wrote: post #57

Most of the ocean is desert lacking the limiting nutrients of nitrogen, phosphorous and iron. If we can cheaply fertilize large swathes of the ocean with these limiting nutrients in a controlled manner, then this could trigger massive algae blooms that on sinking sequester massive amounts of carbon.

Unfortunately, fertilizer presently has a large carbon footprint

it depends on the final balance. As mentioned above the ratio for iron is 13k Carbon atoms sequestered for atom of iron.

Keep in mind the vast majority of agricultural yield growth the last century is giving these limiting nutrients as fertilizer for plants, so it is successful and worthwhile for land based farming atleast.

Re: Could seaweed be the 'fastest and least expensive' tool to fight climate change?

#152

Post by analog31 »

ben_w wrote: post #86
analog31 wrote: post #63

Earlier quoted context omitted.

Unfortunately, fertilizer presently has a large carbon footprint

Many crop fertilisers have that issue, but fertiliser is not only one thing. One hypothesis is that algae are limited by some single resource which could be gradually dropped out the back of cargo ships as they cross oceans, seeding carbon-absorbing algal blooms as they go. (I heard about this nearly 20 years ago, so I assume that has either been tested or banned since then…)

I'm thinking mainly about the Haber-Bosch process, which runs on methane, and feeds more than half of the world's animal population.

As mentioned in a sibling comment, it could run on some other heat source, but that hasn't been demonstrated yet on the scale of agriculture.

Re: Could seaweed be the 'fastest and least expensive' tool to fight climate change?

#153

Post by munificent »

WastingMyTime89 wrote: post #124
munificent wrote: post #113

Earlier quoted context omitted.

I think it's interesting that Homo sapiens evolved during the last ice age where the climate was significantly different than today's climate. We already "won" a major climate change once despite having a level of technology barely better than sharp sticks and pelt cloaks. Instead of defining success based on climate stability itself, I think it makes more sense to define success in terms of what we care about: a thr…

> catastrophic loss of human population At the same time, the population has been booming to the point that close to half of the humans who ever existed are alive on Earth right now. This is a significant part of the current crisis actually.

True, but that curve is flattening out. The UN predicts human population will peak 10.43 billion in 2086 and begin to decline from there:

https://ourworldindata.org/future-population-growth

(Obviously, the error bars for a prediction like that are large.)

Many developed countries are already losing population:

https://www.worlddata.info/populationgrowth.php

An even larger fraction of developed countries would be losing population already if it wasn't for immigration. This suggests that as the developing world becomes more like the developed world, human population will be less of a concern for the global environment.

My perhaps radical position is that two best solutions for surviving climate change are birth control and education for women. The fewer people we need to keep alive, the more easily we'll be able to adapt to the changing climate.

Re: Could seaweed be the 'fastest and least expensive' tool to fight climate change?

#154

Post by WastingMyTime89 »

munificent wrote: post #153
WastingMyTime89 wrote: post #124

Earlier quoted context omitted.

> catastrophic loss of human population At the same time, the population has been booming to the point that close to half of the humans who ever existed are alive on Earth right now. This is a significant part of the current crisis actually.

True, but that curve is flattening out. The UN predicts human population will peak 10.43 billion in 2086 and begin to decline from there: https://ourworldindata.org/future-population-growth (Obviously, the error bars for a prediction like that are large.) Many developed countries are already losing population: https://www.worlddata.info/populationgrowth.php An even larger fraction of developed countries would be losi…

Yep and there is broad disagreement regarding when the peak will be. I remember at least one analyst for a large found implying it would be much sooner that what the UN model predicts. It’s apparently surprisingly hard to give good long term prediction for population growth.

I think it’s a bit late for what you are proposing however. Most of the world population is quite young.

Re: Could seaweed be the 'fastest and least expensive' tool to fight climate change?

#155

Post by selimthegrim »

webnrrd2k wrote: post #150
dubcanada wrote: post #42

Earlier quoted context omitted.

While I agree, how do you recommend we reduce emissions immediately, which is basically when it needs to happen. It seems like largely people just don't care about the environment on a "general global" scale. There are pockets are people/groups/countries that do. But on average people don't. So that leaves really one solution, which is attempting to reduce the amount of existing emissions to stop the rise to some deg…

As a possible alternative to teducing emmisions, I remember reading that the eruption of Mt. Pinatubo lowered the earths temperature by about half a degree for three years [1]. So maybe there is a way to trigger another volcano. Or a nuclear explosion? I know... These are horrible, horrible ideas. And they really reinforce the "people don't care about the environment" thing, too. Maybe someone has better ideas? [1] h…

It also decreased ozone in the stratosphere at many latitudes, not just the Philippines’.

Re: Could seaweed be the 'fastest and least expensive' tool to fight climate change?

#156

Post by lotsoweiners »

etrautmann wrote: post #135
standardUser wrote: post #126

Earlier quoted context omitted.

It's hard to imagine how someone can look at the track record and then think "impossible! we will never figure it out!" when human history is basically a detailed record of us constantly "figuring things out" that previously seemed impossible. When something has yet to be figured out you are supposed to be baffled because the part where it all make sense doesn't come until after we figure it out. It doesn't guarantee…

I appreciate the case for optimism, and I agree that as a species we can be quite clever. We can also fail to address important issues with simple and obvious fixes in ways that boggle the mind (e.g. getting vaccinated or wearing masks during COVID). Whereas I might have once thought that our ingenuity would rule the day, it seems like a functional society requires more than just technology.

Getting vaccinated wasn’t an option during the halcyon days of Covid and like 95%+ of people I saw at public businesses in my red state were wearing masks (or at least attempting to) during that time period. But unfortunately people still needed to eat, work, purchase necessities, learn, get treated, etc. This all to say that I don’t really think your analogy really holds up in this context.

Re: Could seaweed be the 'fastest and least expensive' tool to fight climate change?

#157

Post by selimthegrim »

thechao wrote: post #53
gdudeman wrote: post #40

Earlier quoted context omitted.

I like this back-of-the-envelope estimate, but it's even worse than that. The carbon in oil is lightweight relative to the two oxygens it combines with (atomic weights 12 and 16 respectively) from the air, so 1kg of oil emits about 3kg of CO2! Punchline: we emit around 34 gigatons of CO2 per year.

My argument is that we're probably going to kill the Gulf of Mexico, anyways, with global warming; so, let's go ahead and dump 34 gigatons/year of serpentine in it. That'll 0-out the CO2 we're releasing, at the cost of dramatically changing the Gulf's ecosystem. At this point, I really do think we (humanity) are going to have to make some pretty hard trade-offs.

What changes do you anticipate?

Re: Could seaweed be the 'fastest and least expensive' tool to fight climate change?

#158

Post by [deleted] »

worik wrote: post #75
pvaldes wrote: post #60

Earlier quoted context omitted.

If you think that you can obtain a permit to put such eyesore as a seaweed farm in front of Copacabana, well... good luck with it. But we could of course build it in the middle of nowhere, and then spend lots of fuel to move the product to the far-far-away markets, and even feel good about our ecological trace for a couple seconds.

> permit to put such eyesore as a seaweed farm in front of Copacabana, well... good luck with it. I think you should think about what I actually said. Copacabana is right by a port > But we could of course build it in the middle of nowhere Often, in ,any places, wild and unpopulated wet bits are right beside transport routes on the dry bits. Less than twenty miles from where I sit

[deleted]

Re: Could seaweed be the 'fastest and least expensive' tool to fight climate change?

#159

Post by selimthegrim »

pvaldes wrote: post #60
worik wrote: post #43

Earlier quoted context omitted.

> Coastal areas are extremely busy. No. Ports are busy. The coast is huge. Most of it, on the wet side, is mostly not busy at all Sea lanes are further out, land dwellers on the dry bit.

If you think that you can obtain a permit to put such eyesore as a seaweed farm in front of Copacabana, well... good luck with it. But we could of course build it in the middle of nowhere, and then spend lots of fuel to move the product to the far-far-away markets, and even feel good about our ecological trace for a couple seconds.

Yes tell us more about the notably clean bays of Rio de Janeiro

Re: Could seaweed be the 'fastest and least expensive' tool to fight climate change?

#160

Post by aydyn »

nologic01 wrote: post #99
leesec wrote: post #87

Earlier quoted context omitted.

>There won't be any ingenious, miracle carbon removal solutions OK but I think there will be.

Technically there might be. There is plenty of brains around to explore all possibilities and there are far worse ways to waste talent. Just don't bet the planet on it, don't create a sense that a painless fix is just around the corner and then we can simply go on.

There's no other possibility except a technical solution. Expecting humans to change their behavior collectively, across the globe, is magical thinking.
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