I have recently become aware of two camps of thought with regard to global warming/climate change, niether one relating to religion vs science. On one side is the internationally recognized theory of rapid devastating change and on the other a token uncertainty of the actual changes occuring in terms of what effects we may be facing and how quickly they will emerge.
As a "regular sort" I don't really know a lot of the science involved with our changing conditions and so I guess that puts me in between the two in this arguement. They both have very valid points and the answer to this riddle is important- so what do you all think?
(1) Almost 3/4 of the planet is covered by water, therefore ocean systems are probably calling most of the shots. Some of the players: ENSO in the S. Pacific, PDO in the N. Pacific, AMO, AO & THC in the Atlantic. We don't understand what causes any of these systems to change, and can't predict any of their behavior. And yet we can predict the effects-- 100 years into the future-- of modifying the atmosphere by trace quantities (~50ppm)? Seriously?
(2) Assuming there actually *is* a problem, there are basically two strategies for dealing with it: Prevention and mitigation. Prevention is staggeringly expensive, and has huge hidden costs/risks. For example, what if we have the science completely wrong (remember, I'm assuming there is a problem, which I don't concede)? Prevention costs just as much, but mitigation costs nothing. And many of the things we would do in a mitigation strategy gain us some benefit whether we're right or wrong. Even if there is a problem, there are certain to be some beneficial effects. With prevention we prevent them, too. With mitigation we get to keep them. And then there's the fact that the best we can do with prevention is status quo. More than 1 million people die of malaria ever year. "Doing something" about GW can't prevent a single one of them. For $5B USD we can develop a vaccine and virtually eliminate malaria. And IMO the clincher is that we have to do mitigation anyway. If we have awesome power to change climate there are going to be some awful effects of spending hundreds of trillions of dollars. We'll have to "do something" about them.
(3) The apocalyptic scenarios we keep hearing about are extremely unlikely. After all, if our meddling can cause, for example, a mass extinction, we really shouldn't be here to talk about it. After all, some really extreme things have happened to this planet. If we can cause such havoc, they should have wiped out all life on Earth forever.
John C, your first sentence is a non sequiter and your first paragraph is an argument from ignorance. You can't conclude that we have nothing to worry about from the fact that you don't know how the ocean systems affect climate. Particularly when climate is clearly changing, highly correlated with the increase in CO2. And of course, that CO2 is a trace gas is irrelevant. That it is a known insulator and that its presence in the atmosphere has risen from 280ppm to 390ppm since the start of the Industrial Revolution is relevant. A trace gas may very well have effects out of proportion to its percentage of the gases in the atmosphere, as CFCs did with the ozone layer. In percentage terms, the increase in CO2 is dramatic: Almost 40%. We do understand how greenhouse gases affect our planet's retention of heat. We may not fully understand how the oceans react (though I think we know more than you think we know), but the trends are unmistakable and there's no reason to think the oceans will save us from greenhouse warming. Who knows? Maybe they'll exacerbate the problem. That's why an argument from ignorance doesn't work.
You cite no sources in your second paragraph, but hundreds of trillions of dollars is certainly a wild exaggeration. In any case, a cost/benefit analysis that doesn't consider benefits is meaningless. We may well save more than we spend by keeping global warming to a minimum. And if we do prevention correctly, the money we spend now will spur a new wave of innovation and wealth creation. That the oil and coal companies will lose out is irrelevant if others gain. If the oil and coal companies are smart, they will lead the change. Many oil companies already are major players in the renewable energy market.
Your third paragraph makes an unsupported assertion about the likelihood of apocalyptic scenarios, followed by a non sequiter. That our meddling has yet to cause our own extinction has no bearing on our future potential for self-destruction. Just because it hasn't happened yet, doesn't mean it can't.
(1) This is not argument from ignorance. My point here is not "we don't understand, therefore there is no problem". It is to reject the absurd air of certainty surrounding the issue.
(2) Bjorn Lomborg has estimated the cost at $500 T US, worldwide, over the course of the century. The world's economic production is about $61T/year. Assuming a growth rate of 2%/year, that's 2.6% of the 21st century's economy. We're talking about changing the way every human being on the planet gets food, shelter, clothing, etc. 2.6% sounds conservative to me.
(3) Imagine the consequences of the last eruption of Yellowstone on top of the climatic fragility claimed here.
1) You are still making an argument from ignorance: You claim we don't know how ocean systems affect climate, but you are assuming that those may somehow counteract the damage we are doing to the atmosphere. You are arguing that we should wait to act until we do know everything about how ocean systems affect climate, rather than work to reduce the damage that we do know we are causing.
2) I'm not that impressed by Lomborg, but in any case, like I said, a cost/benefit analysis must include both costs and benefits. The NRDC says the cost of remediation could be as high as 3.6% of global GDP, so even if we spend 2.6% of global GDP to avoid it, we'll come out ahead. Even if we only break even, we'll have the nice side benefit of living on a planet we haven't totally wrecked.
3) Your point seemed to be that if humans were going to destroy the planet, they would have done so by now, which is not logical or relevant to whether we should try to avoid destroying it thru inaction. And whether Yellowstone's supervolcano pops off again is irrelevant. We can't do anything about that. But we can do something about AGW.
It's already rising, albeit at a slow, but accelerating pace. The Maldives are likely to be uninhabitable due to more frequent storm surges within a few decades. At current rate of sea level rise, inundation will take considerably longer, but again, the rate is increasing and could speed up even more in a hurry if Antarctica starts melting faster than it already is.
Sure. Feel free to trash this as inconclusive or insufficiently alarming, but I wouldn't be buying any Miami beachfront. Well, anything in the southern half of Florida, for that matter. Or Bangladesh, or Tuvalu, or the Maldives, etc. Even before they go underwater permanently (or if they never do) storm surges are already often higher than the highest elevation in these places. A direct hit from a hurricane would render them uninhabitable for months. Precedents here and here. Even a very small rise in sea level without more powerful storms will dramatically exacerbate damage from storm surges in relatively flat areas near sea level.