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We Have Four Years to Save Ourselves from Climate Change, Harvard Scientist Says

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Re: We Have Four Years to Save Ourselves from Climate Change, Harvard Scientist Says

#151
post #148
post #123

Earlier quoted context omitted.

Dramatically reduce the amount of CO2 we produce. That's not going to prevent all problems, but if we do enough, it will prevent the worst problems. We really need to aim at zero CO2 production. We will fall short of that goal, but everything will help slow things down, and eventually bring temperatures back to what they were, after natural plant growth has gotten the time needed to remove CO2 from the air again. Onc…

How do you propose we reduce CO2 production to zero?

We need to get rid of fossil fuels, of course. Firstly, the use of coal and oil simple electricity generation. Replace it with hydro, nuclear, solar, tidal, geothermal, I don't care, but we need to stop burning coal and oil in power plants. Gas is the last we'll get rid of; it burns cleaner and more efficiently than coal and oil, and more importantly, it's great at adapting quickly to changes in supply or demand, and we're going to need that as long as we don't have sufficient high capacity energy storage yet. But once we do, gas too will have to go.

We're also burning oil in cars of course. Fortunately, electric cars have become incredibly popular thanks to Tesla. Once electricity generation is clean, electric cars are perfect for taking advantage of that.

Planes and ships are going to be hard. On top of that, many ships burn incredibly dirty oil, and the fuel for planes and ships is untaxed, which, in a world where all other forms of energy are taxed, make them effectively subsidised. International treaties are necessary to make ship fuel cleaner, and extra efficiency may be encourages by taxing fuel. For short distances, planes may be replaced by high speed trains, but for long distances, I don't think we'll be able to get rid of them.

Fortunately, there are other things we can do: trap CO2 from the atmosphere by planing trees, encouraging other plant growth, and possibly even stimulating algae growth in the oceans because that's where the real large scale capacity for this is. There might be other ways too.

At least in part, this can be accomplished simply through better policies by governments, maybe international agreements. But to encourage businesses and people to burn less carbon, I think a growing tax on the emission of CO2. I don't see the cap-and-trade working very well, and even if it does, it merely limits it; it doesn't bring it back to zero. A carbon tax can do that. I think the carbon tax should start low, because you don't want to kill the economy with crippling taxes, you just want to make it attractive to switch to cleaner energy. The tax should then be used to either invest in cleaner technology, or to directly remove CO2 for the atmosphere. You could even pay companies to do that for you, creating a new industry that cleans up the pollution from those businesses that are unable to make the switch for whatever reason. At first, the tax won't be enough to clean up all CO2, but eventually it definitely should be. And once you're there, it doesn't really matter if some people or companies still pollute, as long as they're also paying to undo that damage again.

Re: We Have Four Years to Save Ourselves from Climate Change, Harvard Scientist Says

#152
post #113

Earlier quoted context omitted.

>Even if we completely stop emitting CO2 right now (which we can't), there would still be too much CO2 in the atmosphere for some time, leading to further heating and longer melting Do you have any data on this? If you look at how quickly things cool off at night, Earth's biosphere reaches steady-state thermal equilibrium over the course of a few days. Your claim is essentially that we've already set off an albedo fo…

Well, the CO2 in our atmosphere is too high, and it's been built up over the course of more than a century. It won't immediately drop back to normal levels even if we did somehow manage to stop producing any CO2 at all. At night the temperature drops not due to a lack of CO2, but due to a lack of sunlight. If we were to be able to partially block the sun, or reflect significantly more sunlight back into space, we wou…

http://www.niac.usra.edu/files/library/meetings/fellows/mar0...
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