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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?

#101

Post by euroderf »

sacnoradhq wrote: post #91
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.

It doesn't take an unreasonable amount of iron and the sequestering efficiency is 13k:1 C:Fe on a molar basis. https://en.wikipedia.org/wiki/Iron_fertilization

Do you mean rather: 1:13k Fe:C

From that Wikipedia item,

"Each iron atom converted at least 13,000 carbon atoms into algae."

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

#102

Post by euroderf »

chungy wrote: post #49
Ingaz wrote: post #45

Hm. Is that seaweed is edible by other organisms? Then: more food -> more organisms -> more CO2 It's a level of middle school

Humans eat seaweed all the time.

Tangentially: the Japanese rice crackers wrapped in seaweed are num.

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

#103

Post by rickydroll »

ravenstine wrote: post #78
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.

Would we have to continually fertilize the ocean? And at whose expense? It'd be great if such an operation could be profitable, but it there's only so much seaweed people can eat.

need more whale poop to keep the fertilization cycle going. https://www.newscientist.com/article/2309262-scientists-want...

https://www.dw.com/en/artificial-whale-poop-could-save-the-p...

and burning Australia is a proven way to generate more plankton. https://nicholas.duke.edu/news/australian-wildfires-triggere....

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

#104

Post by euroderf »

oezi wrote: post #71
eklitzke wrote: post #32

It's a cool idea but I don't see how this is a viable long term solution, even if done at a large scale. Global oil production is on the order of 90M barrels/year, each barrel contains about 300 lbs of oil, so we're currently producing something like 27B lbs (~12B kg) of oil per year. I'm not sure how much of this ends up as CO2 in the atmosphere versus e.g. plastics, but I think it's safe to say we're probably emitt…

Looking at the technology trajectories of PV and wind it is pretty clear that within the next 5 to 15 years many countries will start seeing substantial extra electricity being generated by the build out of renewables. Because countries will aim to cover most electricity by renewables and thus overprovision them for dark windless winters, it is likely that there will be massive amounts of energy available during the…

So, how do you apply this to carbon sequestration in seaweed ?

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

#105

Post by mhuffman »

alas44 wrote: post #70
variant wrote: post #65

What does success look like in the climate change fight? Is there a point where victory can ever be declared? Is that a "correct" temperature (what is it) or a CO2 PPM number (what's ideal)? When industry and scientists stop lobbying for money to fight it?

Ideally, pre-industrial levels of CO2 ppm and stabilization of planetary scale changes (ocean dilatation, melting of glaciers etc). Because of inertia at this scale, for the second part we are already in trouble, even if we were able to magically stop emitting CO2 today

>Ideally, pre-industrial levels of CO2 ppm and stabilization of planetary scale changes

I don't see how this is possible with our current population growth trajectory.

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

#106

Post by nologic01 »

bjelkeman-again wrote: post #94
nologic01 wrote: post #82

There won't be any ingenious, miracle carbon removal solution and various proposals may even be flirting with ecological disasters of planetary proportions. Anything that expands our footprint in order to mitigate our footprint is a dubious direction. Reminds of an apprentice wizard that panics and invokes a sequence of spells, each one worse than the other. Discussions and thinking around sustainability underestimat…

The Planetary Boundaries framework, extended from the original article in Nature [2] in 2009 is a good way to look at multiple of the Anthropocene symptoms. [1] https://www.stockholmresilience.org/research/planetary-bound... [2] https://www.nature.com/articles/461472a

In the modern era (and for Western cultures) there was a cognitive revolution that started around the time of Carl Sagan's Pale Blue Dot moment.

The Planetary Boundaries concept is in a sense the evolution of that initial internalization, the beginning of a more analytical approach towards long-term sustainability (a first UML diagram of our predicament if you wish).

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

#107

Post by euroderf »

gdudeman wrote: post #40
eklitzke wrote: post #32

It's a cool idea but I don't see how this is a viable long term solution, even if done at a large scale. Global oil production is on the order of 90M barrels/year, each barrel contains about 300 lbs of oil, so we're currently producing something like 27B lbs (~12B kg) of oil per year. I'm not sure how much of this ends up as CO2 in the atmosphere versus e.g. plastics, but I think it's safe to say we're probably emitt…

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.

This is the part that car drivers don't get cos neither they nor any journalist does the math. Maybe visualisation would help.

Consider: One gallon of gas. [rest of world: liter]

1) How much CO2 does its combustion generate ?

2) How much does that CO2 weigh ?

3) At 100% concentration and sea level atmospheric pressure, how many Olympic-sized swimming pools (or football stadiums) would that CO2 fill ?

4) At current ambient concentrations (CO2 ppm), what volume does it fill ?

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

#108

Post by jansan »

mordymoop wrote: post #67
jansan wrote: post #22

No, blowing H2S and SO2 into the stratosphere is cheaper.

So many different cheap, easy options to at least partly remedy the problem and possibly reverse it, but the only possibility seriously discussed is a civilization-destroying and politically unrealistic austerity.

Even doing nothing would probably have a better outcome than what is being done right now.

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

#109

Post by developer93 »

nologic01 wrote: post #82

There won't be any ingenious, miracle carbon removal solution and various proposals may even be flirting with ecological disasters of planetary proportions. Anything that expands our footprint in order to mitigate our footprint is a dubious direction. Reminds of an apprentice wizard that panics and invokes a sequence of spells, each one worse than the other. Discussions and thinking around sustainability underestimat…

A quote from the book overstory comes to mind: "we're seeking technological solutions to a social problem."

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

#110

Post by mcguire »

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.

Algae blooms result in de-oxygenated water, no?

(Among other consequences.) https://www.cdc.gov/habs/environment.html

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