[robomartin]

> Also what are you even trying to argue with that second bit?

A number of things. Perhaps the most obvious of them being that any proposed magical solution has to be compared to common sense baselines. We never do that.

Eliminating ALL of the US and China (as in: They evaporate from this planet and cease to exist) can't fix the problem. At all.

Taking that as a simple factual baseline, I can't think of a single proposed so-called solution that even begins to compare to such an extreme, much less actually reduce atmospheric CO2 concentration.

The fact of the matter is it will take 50K to 100K years. We can kill ourselves in the process. We are not going to make it happen faster. We can't do that. We would have to violate the laws of physics. That tends to fall under the "impossible" category.

[Schroedingersat]

Stopping it from increasing is overwhelmingly simple. Just stop digging up carbon and stop releasing carbon tied up in ecosystems. The methods for getting energy without fossil fuels are accelerating at 20% or so per year, and last year displaced about 1-2% of carbon producing final energy. Luckily noone is proposing solving the problem by Thanos snapping a quarter of the population, so you don't have to worry about something as obviously idiotic as that not helping.

As to removing it, there are on the order of a billion with enough wealth to wield about 10kW without dropping their quality of life below the people they stole the natural resources from. This is enough energy for direct capture and sequestration of 10-20 tonnes of CO2 using industrial means per year using current technology. There are also many biological means that would have even greater impact just using a fraction of the land used for pasture.

There is no technical limitation to undoing the damage in a century or even a few decades, merely one of political will.

So I reiterate. What is your point of bringing this up? Why are you repeating this? What are you even trying to say?

[robomartin]

> There is no technical limitation to undoing the damage in a century or even a few decades

That's where you are wrong. That's where all of these hand-wavy so-called solutions are wrong.

It is impossible to do this in a century.

It is impossible in anything even remotely close to a human time scale.

A 100 ppm reduction in atmospheric CO2 takes a minimum of 50,000 years and, more than likely, somewhere in the range of 100K.

So many things people ignore in these arguments. For example, world-wide population will nearly double by the end of the century. We are 8 billion today. Even if we take a low estimate of about 11 billion, that's adding the equivalent of TEN USA's, two India's or two China's.

Imagine that. Add two China's to the planet and actually claim that we can UNDO atmospheric CO2 concentration inside of a century.

C'mon! Give me a break! Get real!

[Schroedingersat]

Enhanced weathering experiments indicate that slreading basalt dust over agricultural land in quantities roughly equal to iron tailings (a large portion can be thise exact iron tailings as it is often basalt hosted) would sequester 1ppm per year whilst improving yields. It is not enough to offset current activity, but it is enough to bring levels down to something less bad in fairly short order.

This is just one of many possibilities.

The last resort one is iron seeding the lowest-life portions of the pacific. It is proven to work at many times higher scale for much lower cost, but the potential harms are not yet fully understood.