Its a pretty lousy argument.
It assumes that the worst as a realistic possibility. It assumes away the possibility that CO2 emissions could keep us from harmful global cooling (a lower probability but not zero, if you assume that a possibility of horrible results means you have to avoid an action or take action to avoid the results, then that argument would also imply we have to take action against cooling).
Even ignoring cooling, a small fraction of resources that would be spent or never generated because of a crash program to fight global warming, could save much more lives that anything global warming is likely to do, both from dealing with actual current severe real world problems, and from using some fraction of that wealth to avoid potential future risks that are low probability like the worst global warming scenarios, but that would be even worse.
Beyond that is the question of whether a crash program of against global warming is necessary or sufficient to avoid disaster, if disaster is a real possibility. And the related question of whether anything America can do, or America and any other country that's likely to go along, would be necessary or sufficient. If its not necessary, if action later after technology has developed can deal with the issue for far less money, then even if the worst scenarios are realistic, spending trillions on avoiding global warming in the near to mid term future would have been a mistake. If its not sufficient, if action to suppress CO2 emissions by the US just moves production to China or elsewhere possibly causing more CO2 to be emitted, or if even if we can get China to go along with the program and its still not enough, then you spent vast resources, causing the world to be poorer, and leaving less wealth left over to mitigate the impact of global warming.
To justify "spending" (meaning both spending and never generating in the first place combined) such huge fortunes on an effort to stop a disaster you don't just need an idea about how bad the disaster will be, but how likely it is, and how likely spending the money would be to stop it.
One of the major asteroids, not one a mile in diameter but one of the largest ones, say Vesta, hitting the Earth, would be a disaster far worse than anything human emission of CO2 could create. Why don't we spend trillions on keeping Vesta from hitting the Earth? Well because its in a fairly stable orbit far from Earth, its chance of hitting Earth over the next million years is close to zero. Also if it was going to hit Earth, we can't do anything about it now. Another example of the same thing (not as bad, but still a massive calamity, much more likely to happen, but still very unlikely to happen soon, and even harder to do anything about) would be Yellowstone erupting.
Obviously I took an extreme examples, to demonstrate the point, but they are only shown as extreme examples when you consider the possibility of the disaster, and the possibility of the proposed action doing anything to help (and not causing other similarly severe problems, or using up resources needed to cope with the problem if the prevention efforts fail). |
