The reason they aren't concerned about global warming is that they haven't used their brains. Self-interest is a powerful argument, always, but this is what they think is true. What is actually true is that climate change (and broadly, our impact on the environment) will end most ocean life. It will do things to biodiversity that we don't fully understand yet. When those rich conservatives get cancer and learn that the cure they need was eradicated along with some species of ivy in central Brazil 20 years ago, they may regret their naivete. And so on. Foreign Affairs has been hitting the arctic passage "benefit" of global warming pretty hard lately. I get it. It's short term profit (huge profit). And in the very short term, "a little warmer but no worse off" is probably accurate for just about everyone in America. So fuck Tuvalu. But in the not so long term, say 50-75 years, the northern hemisphere is going to feel major lifestyle changes (unless technology somehow saves us again, as mk mentions above). EDIT: I should clarify that I don't really disagree with you but I thought what you said needed a small caveat.Climate change, however, will largely impact the sensitive populations and sensitive climes around the world, leaving the wealthy, northern-hemisphere 1st world a little warmer but no worse off.
This is one reason why you see so few conservatives concerned with global warming - for them, "water wars" are an abstraction. A navigable Northwest Passage? Now we're talkin'.