I always want to suggest to these people that they should start smoking, because clearly, the future's so bright there will be a cancer cure soon.

And, not to be too crass, but that admittedly snarky reply is about one body. The geoengineering proposals are about intentionally influencing a hugely complex system we still don't fully understand, and that is undergoing changes with implications we don't fully understand. All the talk about ecological engineering seems to assume that the worst that happens is it doesn't work. That sort of naive optimism would be cute if we weren't literally talking about the planet. And if at least some of it weren't duplicitous.

This isn't the reason I chose not to have kids, but it sure does reaffirm that choice. Perhaps the Drake pessimists are correct, and intelligent life can't get off-planet before offing itself.

There is evidence to support what you are saying: every year there is new research that brings the inhospitable-deadline closer to today - there is a high degree of uncertainty. However, assuming that humans are at the very least responsible for the acceleration of climate change by pumping out GHGs, we could start by reversing that single change that we have made.

It's not as though we should just give up.

You might be reacting to my parting, pessimistic shot - that's fine. I don't think we should give up either. I'm just not optimistic when it comes to humans and collective action problems.

[1] details may be incorrect; I haven't paid a ton of attention to the specific proposals.

I really hope that I am proven wrong about it being too late due to trapped GHGs (but we can still try).

[1]: http://ewn.co.za/2016/08/22/Victory-for-DA-as-Herman-Mashaba...

No, you really can't, or we wouldn't have year-after-year record breaking temperatures. Regulation has never fixed anything. And especially when it comes to science, we need to remember that innovation and regulation are opposite ends of the same spectrum.

That's just silly. Regulation guarantees the safety of the food you eat, the buildings you live in and the car you drive.

After all, check out this thread: https://news.ycombinator.com/item?id=12340694

But aren't Chinese shops much more heavily regulated than the ones in Hong Kong. I've always understood China as a very heavily regulated bureaucracy and Hong Kong as a bit more free market?

Consider, you might think break inspections would be completely unnecessary because who would drive a car without breaks. However, in states without annual inspections have accidents related to this. https://en.wikipedia.org/wiki/Vehicle_inspection_in_the_Unit...

Would that be because you know you've just made an unsustainable statement. Regulation has prevented plenty of ills.

that's a shame. how could we fix this? perhaps... regulation against lobbyists?

The problem with pretty much any regulation actually implemented is that politicians have been way too eager picking winners (massively subsidising specific approaches instead of letting a thousand flowers bloom) and protecting losers (assigning emissions trading credits to existing big polluters, essentially shielding the organisations that need them the most from incentives, while burying newcomers in cost and red tape), creating an opaque web of perverse incentives and an orgy for lobbyists.

If it costs $100/day to heat your home in the winter are you going to pay that or buy black market kerosene or just chop down a tree and burn it when no government inspector is around?

There's a limit to how much can be done with taxes.

Second, the revenue from the carbon tax should be fed back to the people by lowering other taxes. It should be net-zero on the government budget. The point is to create a clear and simple incentive across the board to switch to low-carbon behaviour, not to raise revenues.

Third, nobody promised this would be a quick fix, but nothing is at the moment. But re-jiggering the economy to give a clear incentive is a good start, and even at $7/ton, reducing carbon becomes a multi-billion dollar industry overnight.

1: http://www.carbontax.org/blog/2008/10/18/a-question-of-balan...

That's 16.5 tons per man, woman, and child, right? So potentially over $1,000 for a family of 4.

> Second, the revenue from the carbon tax should be fed back to the people by lowering other taxes. It should be net-zero on the government budget.

The bottom 50% of earners currently pay about 3% of Federal taxes. So if you are planning on replacing the progressive income tax with a carbon tax I think you're going to run into pretty substantial problems with regressive brackets massively increasing taxes on the lower and middle class.

Total US emissions were 6.8 billion tons. At $7/ton that's about $50 billion or 1.5% of total Federal tax receipts. Sounds like no big deal, right? But for the bottom 50% it's a $25 billion tax hike on their existing $100 billion bill -- you've just raised taxes 25% on the bottom half.

https://www.epa.gov/ghgemissions/overview-greenhouse-gases

A carbon tax is decidedly not progressive. Take a look at the carbon map [1] of the 'Americans Carbon Footprint' and you will see, the problem is not the rich motoring around in their their yachts.

Now, the biggest factor in carbon footprint is the zip code you live in -- due mainly to energy use and transportation costs. So does a carbon tax vary based on the zip code of your primary residence? Seems absurd to me. So we have to start by admitting that any carbon tax we do come up with may not actually tax a large part of your carbon emissions. Which is to say, it likely would unfairly target certain products based on their carbon footprint while giving a free pass to others. While taxing some carbon might seem better than taxing no carbon, IMO a tilted carbon tax is worse than no carbon tax.

A gasoline tax approximates transport carbon footprint. It also makes electric and public transit more desirable. You can certainly also tax electric/natural gas/oil based on their footprints. This would be effective, but again, regressive.

If you take out the part where people are paying for their carbon footprint and go back to just taxing the rich, it's not really a carbon tax anymore.

It's not like people can report their carbon footprint on their 1040. The only way to tax carbon is to tax purchases at sale -- let's call it a CAT - Carbon Added Tax. Such a 'CAT' would be regressive.

Generally, if you subsidize purchases which lead to lower carbon footprints, the rich will spend more money on those qualifying items. For example, solar subsidies. This is an example of a non-regressive approach to encouraging carbon shrinkage through the tax code. SolarCity calculated that lifetime net carbon savings of the typical solar install was 150 metric tons.

[1] - http://shrinkthatfootprint.com/american-carbon-footprint

Not to be argumentative, but based on some brief research, the bottom 50th percentile do in fact cover close to 50% of the carbon footprint, and it's the rich, not the poor, who are in a position to cut their emissions by choosing more-expensive/lower-emitting products.

In short, these are two most disagreeable sentences.

That's the goal, no? Burning oil releases CO2. Growing trees and burning them is carbon neutral.

Perhaps planting a tree should incur a negative carbon tax.

Young, inexperienced but passionate fish sometimes have been known to deny the existence of water. Later they're embarrassed.

As long as that inventor doesn't turn out to be a new Thomas Midgley Jr.:

https://en.wikipedia.org/wiki/Thomas_Midgley_Jr.

NB Inventor of both leaded petrol and CFCs.

...

> And especially when it comes to science, we need to remember that innovation and regulation are opposite ends of the same spectrum.

So, regulation has never protected us from the negative externalities of a scientific discovery destructively applied by the market or state? Remember, the state is also subject to regulations - the same free market that fuels your utopian free-market fundamentalist pipe-dreams is protected and sustained by regulation.

The analysis that I'm waiting to see is "of the global CO2 production each year, how much of it is due to humans?"

If we contribute 90% of CO2 production, then reducing it may change things.

If we contribute 10% of CO2 production, then even reducing our portion to zero, the overall change is near-negligible.

The ecosystem produces vast amounts of CO2 ... and consumes a similarly vast amount. It is the imbalance that you need to worry about. And that imbalance is largely caused by humans either damaging CO2 sinks or releasing CO2 that ha been sequestered over the last few billion years

If the faucet is on and your kid is dropping pennies in, both are contributing to the overflow but stopping your kid is going to be irrelevant.

Do we know which humans are?

Of course, turning down the faucet would still help. But in this analogy, the faucet is jammed on, but the kid might stop if you ask him the right way.

For humans, it's pretty simple: we're burning the oil on the timescale of centuries that the nature has been storing on the timescale of billions of years. For nature, the longest CO2 cycle is at most a multiple of the longest life-span (~500 years), and there's no indication that the cycle has changed (i.e. that suddenly more trees are burning in natural fires than have for the past few millenia).

"While CO2 emissions come from a variety of natural sources, human-related emissions are responsible for the increase that has occurred in the atmosphere since the industrial revolution."

Ref: https://www.epa.gov/ghgemissions/overview-greenhouse-gases (on the carbon dioxide tab)

And the Energy Information Association goes on to include magnitudes here:

http://www.eia.gov/oiaf/1605/archive/gg04rpt/pdf/tbl3.pdf

If those numbers are accurate, humans contribute 0.2% of CO2 and 60% of methane. So my follow up is: Which gas is a worse contributor? Because we can greatly influence one of those.

It's a lot like saying "prove it to me with numbers, because all the numbers you're giving me are bunk."

Edit: tense

"Nature generates X million tons of CO2 each year. Humans generate Y million tons of CO2 each year which primarily comes from A, B, and C."

From my own search, there are lots of numbers around X and Y and they're wildly different. Do they converge around a range?

Thus, net CO2 from natural causes must average very close to 0 on long time scales.

PS: If you look into it natural carbon sequestration increases slightly as atmospheric CO2 increase which is why things end up in balance. Natural carbon sequestration is also why there are huge sources of coal and oil to begin with.

Which is to say, the natural net contribution to CO2 in the atmosphere is negative. If we somehow put a stop to natural processes involving CO2 and just carried on with human activity, the rate of CO2 accumulation would go way up.

What?

https://www.co2.earth/global-co2-emissions

This is the relevant bit for how much emitted CO2 has accumulated in the atmosphere:

"From 1870 to 2014, cumulative carbon emissions totaled about 545 GtC. Emissions were partitioned among the atmosphere (approx. 230 GtC or 42%), ocean (approx. 155 GtC or 28%) and the land (approx. 160 GtC or 29%)."

If you want to double-check against increasing CO2 concentration, the mass of the entire atmosphere is about 5.15e18 kilograms, so one part per million is about 5e12kg or 5 gigatonnes.

The preindustrial CO2 concentration was roughly 280ppm. We're now at about 400ppm, so that's 120ppm or about 640 gigatonnes more CO2 in the atmosphere today. Things are a bit confusing here because for some reason emissions are measured in gigatonnes of carbon alone, not CO2, so you need to multiply emissions by 3.67 (the mass ratio of CO2 to just C) to get CO2. Taking the cited 230 GtC added to the atmosphere and multiplying by 3.67 gets us 873.46 gigatonnes, which is roughly in the same ballpark, considering this is an off the cuff internet comment using random googled sources.

One word, CFC