Yes. In terms of policy, I laid this out fairly carefully in a C.D. Howe study I did two years ago called The Morning After, and again in another work I just did for the national round table. If I hear you correctly, it's not good enough to say, “Here's what we're going to have achieved by the year 2050.” That would be a travesty, in my view. What you'd have to do is say, “Here's where the forceful policy instrument, the compulsory policy instrument that I'm talking about, is set in the year 2015, here's where it's set in the year 2025”, and so on and so forth.
If you believe that your policy instrument is something like a carbon tax--that would be one of my two options, something that puts a financial penalty on using the atmosphere as a free waste receptacle--you would literally have to have a graduated schedule so everybody knew what that tax would be five years from now, ten years from now, and so on.
So that's my answer to your question about the link between the long and the short term, and likewise, that would have to be the same if you had a cap on emissions. That schedule would say, “Here's the level of the cap in 2010, 2015”, and so on and so forth. The policy I'm particularly interested in now is something close to what some people call an upstream cap and trade. That means going back to the fossil fuel industries and allowing electricity generators to sell into them.
I call it a carbon management standard, and it's been getting some coverage internationally by researchers and policy designers. It simply involves saying to the fossil fuel industry, “We know that if we're going to get the deep reductions that scientists are telling us we need to get over this multi-decade period, you're going to have to be responsible for the fate of the carbon you extract from the earth's crust.” That responsibility will be small in the first ten or fifteen years--2% of the carbon that you extract from the earth's crust must not end up in the atmosphere--and ultimately it has to graduate on a schedule toward 50%, 80%, or whatever we think we can achieve.
The benefit of that kind of approach is that as you move into the future, though, you may adjust that. The scientists may give you new information that you need to accelerate this or they may give you information that you don't need to accelerate it. You might even slow it down. You may learn more about the costs and find that it's easier to go faster or that you want to go slower. So these kinds of schedules have some flexibility built into them.