[kitsune_]

See, the thing is we don't have 100 years left, because despite what the skeptics might think, climate science is a mature science.

Fourier realized back in 1824, that solar radiation alone is not enough to warm earth to its temperature levels. The effective temperature of earth is around -20°C. Absorption and emission characteristics of CO2 and other greenhouse gases are also well understood, as is the makeup of the atmosphere.

The IPCC's carbon budget for having a 66% chance of staying below 2°C degrees of warming is 1000 billion tons of CO2 starting at 2011. We've already blown 20% of this budget by 2016. We currently emit around 40 billion tons of CO2 per year.

IF developing nations peaked their CO2 emissions in 2025 and then would ramp up mitigation to 10% of emission reduction per annum in 2035, the west would STILL need to start cutting emissions by 10% a year RIGHT NOW and be fully decarbonised in 2035.

You can't engineer your way out of this. The logical, painful and horrible conclusion is that we need to have massive reductions in consumption.

For instance, nuclear, it currently provides around 2% of total energy consumption of the world with 450 reactors. Imagine the amount of reactors we would need to build just to make a dent here... You can't build reactors fast enough. The same with wind, renewables and so on.

[zaroth]

Actually it's even easier to do nothing if you throw up your hands and say it won't work anyway.

The earth will warm more than 2°C from "baseline" no matter what. Now the 1 trillion ton additional CO2 is an interesting benchmark, but I would guess staying under it has very little to do with energy consumption, and almost everything to do with advances in carbon-neutral and carbon-negative power generation technologies to be invented and scaled over the next century.

But not generating the power in the first place just isn't a choice. If it's a hard-line ultimatum I think a billion people could die trying to fight/enforce it.

The takeaway from OP is that climate changes. It changes quite dramatically. And it changes with or without humans in the mix. Maybe we need to spend that $100 trillion getting more adaptable to changing climate rather than entertaining some fantasy that we can control Mother Nature within some sliver of a temperature range relative to her broad historical performance.

[mrottenkolber]

You're not being fair to the OP in saying "it's even easier to do nothing if you throw up your hands and say it won't work anyway."

He gave a very clear way out: massively reduce consumption.

[CJefferson]

Nothing like that has ever been tried before, what would "massively reducing consumption" even mean?

Locking people up who turn their heating up too high? Fines for those who eat too many cakes?

I'm being serious -- I can't imagine how such a thing could be enforced, and you certainly can't count on a significant majority of the world reducing their consumption just because it would be good for future generations.

[kitsune_]

There is actually a very simple solution to reduce consumption: The carbon tax.

Massively reducing consumption means, for instance: * Eating less meat * Frequent flyers massively reducing long haul flights across the world * Getting rid of energy inefficient appliances, such as old refrigerators

Seriously, the pareto principle applies here to, most of the emissions come from a small percentage of people.

If you think about these things from a carbon budget perspective: Whenever you take a flight you effectively rob the poorest of the world of the possibility to use fossil fuels as a way to increase their welfare.

A 2 degrees increase will kill a lot of people. And this will only get worse with a 4 degrees increase. And it will disproportionally effect the poorest of the world. An average warming of 4 degrees means massive warming of the land surface across the globe (Much more than 4 degrees, since most of the earth's surface is covered by water).

The heat wave of 2003 killed tens of thousands in developed Europe. Imagine the heat waves we will get in a 4 degrees world. Our infrastructure is not built for this. Our asphalt roads, train tracks, water pipes, emergency services will all struggle with this. A city like London has maybe food for 3 days.

[Scarblac]

In the war you could only get certain items by handing over a coupon, each family got a fixed number of them.

Should be done for fossil fuel.

[Gravityloss]

On the contrary, consumption changing both ways, growing and shrinking has happened quite often in history.