this post was submitted on 13 Oct 2023
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It ends on a positive though - if the world gets to net zero, then (apparently) no further warming will occur (does this mean runaway warming -from lack of reflection via ice sheets, methane release from previous permafrost zones, etcetera - is no longer expected?).
We just need to push our politicians harder. Poverty and climate are intrinsically linked - we can improve things in the everyday person's life with green investment and policy.
Here's the problems with net zero. First, it's a marketing term more than anything. But assuming it was an obtainable goal, it requires carbon removal techniques that have been shown by prototype and basic math to not be scalable to the task. Making another assumption that such emissions or their equivalent could be removed, we would need to go far beyond net zero into negative emissions to start chipping away at not only continued natural emissions from the mentioned runaway feedback loops already set in motion, but the historical carbon that still remains fro the last century or so of our pollution. If just net zero isn't scalable, the latter is magnitudes greater and impossible.
Net zero is the new "1.5 limit". It's an easy to remember catch phrase for a goal post on wheels. As we pass the old 1.5 mark the new one is used to distract from continued growth of population and consumption, catering to the wired tendencies of our species to procrastinate when danger isn't immediately in front of us. "They'll fix it".
I think the idea that if we can reduce our emissions warming and all that comes with it will also stop is also a subtle marketing being spread because most people don't understand that we're not the sole source of warming, we were just a small catalyst that started the reaction. And with most chemical reactions, at some point the catalyst isn't needed any more to sustain the rest of the reaction. We could stop all emissions right now (whether that be voluntary or not) and the Earth will continue to warm for decades or more just from environmental inertia and breakdown of the system, and then from the addition feedbacks that starts.
The only "fix" for the CO2 issue (which is only part of the problem, but the focus here) is to remove and sequester enough carbon to bring us down to 300 ppm or less, aka preindustrial levels. Put everything burned by our industrial age back into the ground. Entropy alone says that won't happen, calculating the numbers of how much carbon that means is mindblowing. We throw around the giga- prefix like it's nothing, and yet the total carbon we would have to remove gets into the tera- and possibly peta- levels. It's insane.
Net zero is a scam, nothing more. I'm not at all saying we shouldn't change, but don't believe anyone selling you a solution, as change means adaptation and preparation for a different and hostile world, not some science "fix" that will let us keep doing what we've always done.
I'm sure my rant that started as a short reply will get some responses of "what about ___?" Good luck showing me something new that changes the basic math of the problem. It's looking into some of these potential solutions and finding out the real problem that turned me into a hardened skeptic of anything "new". Show me the math that can tackle the numbers, then I'll consider it. In the end you can't fool Nature.
The thermodynamic minimum amount of energy needed to extract CO2 at 450 ppm is 120 kWh per tonne. Current experimental carbon capture plants run at about 5 % efficiency. If we assume we can double their efficiency and can magically produce as many plants as we need, to remove 20 Gt of CO2 per year (half our emissions) we would need 24,000 TWh of energy per year.
That is the entirety of the world's electricity production. To remove half our emissions.
Carbon capture is a non-runner.
Hemp. Nature provides a way to do many things that technology can't do efficiently. Hemp will capture carbon and store 80% in the roots. We would need 5 billion acres of hemp production to remove double our current emissions, I did the math a year ago. That would only be achievable with floating greenhouses, as far as I can figure, but if we hit net zero, then hemp looks much more doable in terms of a long term solution.
Edit: Also marijuana, and we can still use both plants the way we currently do, just store the roots in drums and fill up Yucca Mountain, since we aren't storing nuclear waste there.
Thanks for an example of the numbers. And to point out, the entirety of the world's production of electricity is still over 60% from fossil fuels, so using that energy to undo emissions is ideally a wash, and realistically still an increase. And that's if we turned all of the energy to carbon removal from everything else, which would never happen.
Well yes, but isn't the point to use progressively less fossil fuels - net zero implies we get to a point where we stop making things worse.
From there, then we can start making things better.
Net zero is simply where the emissions we still are emitting are being countered by "something" to have a flatline of human sourced emissions total. Likely the same magic that the IPCC is still counting on, carbon removal tech. It's almost 2024 now and we're starting to see the accumulation of the damage we've done, mainly because things like the oceans have hidden it for so long and are now failing. Time is up.
We absolutely need to reduce fossil fuel use NOW, and as much as possible each year. The damage that will do to our society might be a price no one is willing to pay though, we're very heavily dependent on it, more and more each year. Just a linear decrease means in five years we better be down to 30 gigatons annual emissions, and five more down to 20 gigatons. There isn't a way to do that and keep our modern society (and the up and coming third world industrial countries).
Discussing a Catch-22 situation can become heated, because people don't want the problems pointed out to them without some answers to consider. I'm sorry I don't have any to give. Any that I've ever seen or been presented with are always false hopes, it's a big mess we humans have created.
We're in a bad way until we have ubiquitous fusion, widely adopted nuclear, or some other non-CO~2~ emitting energy.
And those are really tall orders. We need a Manhattan + Man on Moon level effort to even begin to turn this thing around and I'm not see the urgency or leadership from people who'd need to get things rolling.
I followed the links in that quote:
Neither addresses tipping points. They seem to talk about something else entirely, like wether a model assumes constant atmospheric concentration, or constant emissions, that kind of difference.
"Runaway warming", as I understand it, merely describes the outcome, the effects, while being agnostic about the causes. My current understanding is, we ruled out one possible cause. Tipping points like sea ice or methane hydrate are still on the table, AFAIK.