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Comment by OliverJones | Hacker News Reader

Good. Invent things. Try things.

But keep this in mind: plants evolved lignin to make their structures (trunks, branches, all that) hundreds of millions of years before bacteria and other microorganisms evolved the ability to break down that lignin. So, for hundreds of millions of years, plants captured carbon dioxide by photosynthesis and sequestered it. That's what changed earth's atmosphere from reducing to oxidizing. Fossil carbon is the geological remains of that carbon capture.

It's hard to imagine carbon-capture tech that has the longevity of those planet-wide lignin forests.

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Wasn't it cyanobacteria photosynthesis, rather than plants, that significantly changed Earth's early atmospheric composition?

My book: https://impacts.to/downloads/lowres/impacts.pdf

The Great Oxygenation Event occurred about 2.3 billion years ago, around the same time as complex cells emerged. We didn't see multicellular eukaryotic life until 1.6 billion years ago, give or take. Plants certainly played and still play a hugely important role, but they probably weren't responsible for the initial change to an oxidizing atmosphere.

My sources: https://impacts.to/bibliography.pdf

Billion, not million. Interesting book though, thanks for sharing.

Don't phytoplankton still produce the most O2?

That's all well and good, but natural selection has the tendency to only find a good enough solution that happens to work in a niche, not an optimal one for all cases. There may very well be a technique that doesn't work as well in small individual plant-sized systems but can become far more efficient when scaled up. I suppose it is somewhat unlikely though.

As I was reading your comment, I couldn’t help but laugh as it reminded me of the quote “Any idiot can build a bridge that stands, but it takes an engineer to build a bridge that barely stands.”

Scaled up at the continental level, like say, the Amazonian basin?

Scaled beyond a single tree-sized entity I mean. Sure you can put a lot of trees together to do more, but each tree has to do its own small scale sourcing of water, sun, air, etc.

You can take each part of that and make a sizable facility that's dedicated to only handling a specific part very efficiently. As an example, if the process needs electricity you could set up small self contained solar panel units, or you can produce a few magnitudes more with one nuclear powerplant. No point in digging a hole with a thousand spoons when an excavator can do it in one swoop.

I see, thanks for expanding on your point.

Just a detail: forest are not tree next to each other’s. The relationship between organisms change the energy efficiency and life outcome of most of the participants.

> Scaled beyond a single tree-sized entity I mean. Sure you can put a lot of trees together to do more, but each tree has to do its own small scale sourcing of water, sun, air, etc.

Vertical versus horizontal scaling.

> You can take each part of that and make a sizable facility that's dedicated to only handling a specific part very efficiently. As an example, if the process needs electricity you could set up small self contained solar panel units, or you can produce a few magnitudes more with one nuclear powerplant. No point in digging a hole with a thousand spoons when an excavator can do it in one swoop.

Microservices versus monoliths.

Why use a sand blaster when you could polish something by hitting it with one huge rock?

Why have thousands of individual car fuelling stations when everyone could drive to one giant one in the middle of the country?

Why have a steam turbine in your nuclear plant with many small blades?

If your thousand spoons work pretty much untended and cost half a million each, then an excavator that requires a crew of a thousand which costs ten billion is just as stupid as all of the above.

FTR the evolutionary delay hypothesis used to be popular, but for the carboniferous, the most carbon-deposing period on earth, that theory has been dismissed. See this paper: https://doi.org/10.1073/pnas.1517943113

TLDR:

* there is evidence for partial lignin breakdown in existing deposits, so we know it was a thing back then

* if it were just lignin breakdown, then we'd see orders of magnitude more deposits. that is, if you look at the per year deposit rate, you'll see only a small fraction of lignin being deposited.

* a large fraction of deposits doesn't even contain lignin, often below or above deposits with lignin, but without there being a different rate of depositions between them.

That has to make sense. Were there huge piles of dead plants just piling up everywhere? Was it vines all the way to the stratosphere?

Was just going to post this. What a great community!

Was about to google this up. Thanks

Right, just like how you can’t expect to build something that flies better than a bird. They’ve just been evolving at it far longer.

Adding to this CO2 is just one symptom of climate change. Treating a symptom rarely has long lasting benefits whereas curing the root causes may be preferred. Tinkering with just one feedback loop can lead to unintended consequences, a nasty lesson I learned from prescription drugs.

Isn't excess CO2 the literal cause of climate change? What is the actual cause if not that?

CO2 is the gas everyone talks about. Other gases also contribute (CH4, H2O, N2O, SO2, and others).

Yeah because it’s the biggest new contributor. Technically water is the biggest green house gas but there are good reasons for focusing on CO2.

People talk most about CO2 because it has the most total effect as a driver of climate change. CH4 for example has a greater effect per kilogram, but we emit a lot less of it and it doesn't last nearly as long.

H2O technically affects the temperature even more than CO2 but it's not a driver, because the total H2O in the atmosphere depends on overall temperature. Emitting more H2O, from hydrogen cars or something, would just mean you get more rain somewhere.

Yes and:

And it's very likely any fixes will not simply be a matter of reducing atmospheric carbon.

Here's a first principles explanation for why carbon net zero and sequestration are not the direct, most expedient path towards reducing temps.

"Dr. Ye Tao on a grand scheme to cool the Earth" https://www.volts.wtf/p/volts-podcast-dr-ye-tao-on-a-grand#d...

TLDR: Given the time and resources we have, focus on strategies for cooling the atmosphere the fastest way possible.

Maybe most sensible approach: use SRM to reduce temperature directly and head off nasty positive feedbacks like melting permafrost, but treat that as buying time to get CO2 down to a safe level.

Huh? We are clearly tinkering with the atmospheric CO2 levels on a massive scale. But also CO2 is a cause not a symptom. It only becomes a symptom when the solubility of the ocean changes and carbon is released.

Human civilization cycles technologies on timescale of centuries or even decades. No long lasting benefits are needed, just a little while to tide us over to the next better thing. Like burning coal was a giant environmental breakthrough that saved planet's forests from being chopped for firewood and now we have decent nuclear and renewable energy sources that are even cleaner.

I think focusing on longevity in terms of geological timescales isn't necessary. Finding short term solutions will give us more time to come up with longer term solutions before our planet goes completely to hell.

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