Early IPCC reports, all the way up to AR5 basically threw their hands up when it came to permafrost emissions. They admitted we didn't have the necessary data yet and for the most part didn't account for it at all in their models

Check out the 1.5C special report. Go to section 2.2.1.2, last paragraph says

> The reduced complexity climate models employed in this assessment do not take into account permafrost or non-CO2 Earth system feedbacks, although the MAGICC model has a permafrost module that can be enabled. Taking the current climate and Earth system feedbacks understanding together, there is a possibility that these models would underestimate the longer-term future temperature response to stringent emission pathways

https://www.ipcc.ch/sr15/chapter/chapter-2/#:~:text=Geophysi...

You saw our reaction to covid. Millions. It will take millions of deaths in a nuclear armed country. See 'The ministry for the future'

The ingredients for the Syrian conflict came about because of climate change (dried up farms - farmers moving to cities to find jobs - social tension). The last 10+ years has shown that the relatively well-off Europeans would rather watch the Syrians drown rather than "pollute" their luxury enclaves...

We'd rather kill everyone else rather than give up our luxuries...

Are you kidding? It will be Millions easily. It will just take 1 or two blackouts in wet bulb conditions to cause that

We are already far past the point of mere thousands of lives. Entire cities have been wiped off the map by floods.

It will take millions, if not close to a billion lives before we get serious

I wish it were different but I would not be surprised if it’s billions before anything changes. And even then there will be a major proportion of people that celebrate it as the second coming.

That unfortunately doesn’t help with ocean acidification.

Considering the scale that we are burning oil and gas, our sequestration efforts would have to be comparable. Continuing to burn oil and gas and trying to recapture it is madness, like realizing you are driving way too fast and instead of taking your foot off the gas, you keep flooring it but start applying the brakes.

If we could actually grow trees to capture carbon equivalent to 250M+ barrel of oil per day, it would be better to just grow trees and burn them for energy.

It’s difficult to scale this to the levels we would need to make a difference.

The paper states it adjusts for "ENSO, volcanic eruptions, and solar variations" and not (afaict) the changes in shipping bunker fuel that reduced atmospheric SO2 (if that is what you mean by "reduced aerosols"). Below is a summary of the topic for those who are unaware. I withhold any opinion of validity of mechanism or effect.

  Sulphur particles contained in ships' exhaust fumes had been counteracting 
  some of the warming coming from greenhouse gases. Lowering the sulfur content 
  of marine fuel weakened this masking effect, effectively giving a boost to 
  warming.

This is a very common figure you can find much support for. Here’s one legitimate source: Ice Melt | Global Sea Level – NASA Sea Level Change Portal — https://sealevel.nasa.gov/understanding-sea-level/global-sea...

How long would a single cargo-load of shades have to be operational just to offset the amount of CO2 emitted by its launch?

What percentage of the 128-million-square-km cross-sectional area of the earth are you proposing to shade?

Only becomes viable if you have things like Starship online and fully operational, with launch rates at the level of Falcon 9 today. At the minimum.

Still a more viable option than bringing greenhouse gas emissions into the negatives globally, by the way. But that's a low bar. Nuking the ocean floor is probably a better call.

Reducing sunlight to the surface means we lose solar power effectiveness and we need to use more power for artificial lighting to grow plants.

Physically that’s not the case.

Scaled up nuclear power could be had for $3-4B a gigawatt/h. We waste say $1T a year on basic things, like not having universal healthcare. So a simple policy change would let us build about 300 reactors a years, after some scaling period. The excess energy can be used to turn C02 back into oil.

It’s not technically that difficult, we just chose to waste money on stupid things and rich people toys instead.

Energy abundance is simply the choose to build nuclear power plants at scale

If all glaciers and ice sheets on Earth melted, sea levels would rise roughly 65–70 meters (about 210–230 feet). It’s worth noting that a full melt of Antarctica alone would take many thousands of years even under extreme warming scenarios, so this is more of a thought experiment than a near-term risk. Current projections for this century focus on partial contributions, with estimates ranging from roughly 0.3 to over 1 meter of rise by 2100 depending on emissions pathways.

That's been known for a long time - it just hasn't been considered a likely scenario. It's the rise we'd expect if all the ice on Greenland and Antarctica were to melt:

https://sealevel.nasa.gov/understanding-sea-level/global-sea...

This is why it's clear we will never do anything to slow the progression of climate change.

By far the most effective an immediate solution to limiting the damage of climate change is to simply to keep fossil fuels in the ground.

People talk about the economic pain of doing this, but that economic pain is nothing compared to the impact of unmitigated climate change.

Even though this would be painful, it is also by far the easiest and fastest to implement solution. It would take fantastically more time and resources to scale up direct air capture (even if it existed in a scalable format today) to come anywhere near addressing this problem.

> Yes it will take some grid and storage upgrades (US) and continue to embrace renewables

This is not exactly true, we would have to experience global economic collapse in order to reduce our fossil fuel use. 80% of energy is not spent on electricity globally and this is non-electricity usage is where most of the fossil fuels are consumed and this drives most of the global economy. There's a good reason there are multiple wars being fought over for oil.

> We MUST MUST stop burning things.

Yes, we must. It is so rare to see someone saying this in public. Thank you for this simple clarity.

Stop burning everything! Fossil fuel, wood, plastic, garbage, paper. Stop making methane.

We only need solar energy at 1 dollarcent or eurocent (it will get much cheaper still!!) and a little batteries for the convenience of using electricity when the sun does not shine.

In the north and south you need more solar panels in the winter than in the summer by a factor of 50. But that pays it back in summer when you have a squanderable abundance of free and clean energy. We can store that surplus energy in purifying drinking water, melting iron ore or aluminum [5], melting reusable plastics or purifying silicon ingots.

Storing surplus heat or cold in the ground is another luxury, because it is more expensive than 1 dollarcent or eurocent solar running a heatpump.

Wind and hydro are also more costly than solar so they are another luxury with worse environmental costs than pure solar cells.

We need to build Enernet, a peer to peer electricity net and internet between all buildings with power routers. for around 100 dollar per building. You buy and sell your house surplus solar electricity to the neighborhood where it can be stored in car batteries. See my Fiberhood white paper [2].

[1] Enernet: Squanderable abundance of free and clean energy - Bob Metcalfe https://youtu.be/axfsqdpHVFU?t=1565

[2] https://www.researchgate.net/profile/Merik-Voswinkel/publica...

[3] Amory Lovins https://www.youtube.com/watch?v=v02BNSUxxEA

[4] Saul Griffith on the one billion machines that will electrify America https://www.youtube.com/watch?v=iEOPx2X-EtE

[5] 101 million machines away from a zero emission Australia https://www.youtube.com/watch?v=FQ8-uAhG-zs

US, AU?

https://ourworldindata.org/grapher/coal-consumption-by-count...

> Otherwise it doesn't make sense to put CO2 into the air with one hand and take it out with another.

I agree that it doesn't make sense, but I also want to challenge the engineering assumption that an extremely relatively inefficient solution should be ruled out.

If direct air capture worked and simply required absurd amounts of carbon-free power, say from nuclear, it would mean that we no longer have to fight political battles against the entrenched incumbents. They could simply emit whatever our elected politicians let them get away with, and DAC would soak it up.

I completely acknowledge that it seems somehow egregious to do it this way. I am an efficiency-minded person and would hope that we could do it the efficient way. But given all the ugly constraints and lack of progress so far, should we really expect this to be solved the way an efficency-minded engineer might prefer?

If we get to that level of desperation though, I would hope that we could simply pay the emitters to install carbon capture.

What I don't think will work is a politics of rage, righteous or otherwise. I don't recall any incidents in history where a politics of rage led to cool-headed, efficient technocratic solutions. The perennial problem is that the same politics of rage is equally accessible to your opponents, and it spirals down from there towards disorder and violence.

Stopping burning fuel now will return us centuries in the past, I suppose to about 1700. Twenty years ago it would return us to 1500. Then a handful of people had heating in their homes and a horse to travel. This will happen again if we stop burning now.

It's the extreme scenario with all the earth ice melted, even Antarctica. Depending on the model chosen and acceleration this could happen between 2243 and 21861. http://sealevelrise.se/en/earth_slr65.html.

The question is not if the commenter is an expert, but if they are correct.

The claim that some models didn't take larger systems into account is also because an expert in the arctic wasn't an expert in oceans. And the expert in biodiversity isn't an expert in food supply chains. Expertise isn't the question. Instead it is - do all of us who are non experts (all of us) have enough expert data to have a systemic understanding of an accelerating trend?

2 years ago this was hard won knowledge, searching for papers and then putting it all together in survey form for analysis. Today I can tell you: feel free to ask Deep Research or another LLM you trust to do that work for you, generating citations along the way. You can convince yourself vs me having to convince you. It will take about 15 minutes.

Surely the children churning out papers in a memey field, with no real special insight into computational modeling, are the real ones to trust! Their papers are in Nature!

Ridiculous take, and you’d know that the OP was correct if you cared enough to know what researchers were actually saying.

Climate arguments devolve into appeals to impact claimed by authorities rather than any examination of what they’ve said.

Would a PhD student incorporate something into their model that flipped their results from agreeing to disagreeing with the premise that has not only practically become a religion, but forms the foundation for more and more funding flowing into their field each year?

Would they really want to risk being basically excommunicated from their area of research for daring to provide ammo to “climate change deniers”?

It's going to have to be a mixture of approaches. Stratospheric injection buys time for more holistic solutions.

The prospect that the future we're headed for will be one where the survival of civilization (and much of humanity) depends on a massive, ongoing industrial process of upper atmosphere pollution, in order to counteract the massive, ongoing industrial process of CO2 pollution we can't be arsed to rein in, leaves me feeling relieved to be mortal.

We could cease burning all fossil fuels tomorrow and we'd still have to resort to geoengineering. Read the IPCC projections. All of the ones that keep us below 3c require 'negative emissions'. That's code for DAC, a technology that we've only ever deployed to small pilot projects, deployed more widely, more quickly, than we've deployed any technology ever.

TLDR: We're gonna have to use sulfate injection until we can transition our economy

nobody will champion degrowth because it means less profits