Rafe Pomerance:

Well, first, just let me say the prerequisite is political will. For a world leader to ask the question, they have to have the desire to do that.

And, unfortunately, this moment in the United States is one of our worst. Our leader says that this problem is a hoax. So he's taking us out of the negotiations, et cetera.

Given your assumption that world leaders want to step up, there are four areas they have to work in. Number one is R&D, research and development, innovation. We need cheap substitutes. We can do that. We're spending some money, but we — this ought to be a much higher priority on the national scene.

We have an agency that is supposed to come up with radical solutions, changes. It's funded at $200 million, $300 million a year. The Pentagon's agency that does the same thing for the military has had $5 billion. So this has to be a much bigger priority.

Number two, we need to control the other greenhouse gases, like methane, nitrous oxide. And where we can, which is mostly carbon and the energy system, we ought to be pricing it. The tax is the most efficient mechanism we have. It needs not only to exist in the United States. It has to exist globally.

We can do that if we lead. Without the United States, nothing happens. The U.S. Congress is the most important body, I still maintain, in the world on this. And the reason is, they won't act. And if they won't act, our negotiators can't move.

Now, number three is decarbonization. We know how to do that through biological systems, like growing forests, improving soil management and so on. That takes some carbon out. Then there's a whole series of technologies that have been proposed to remove carbon. They're in the early stages. You have to lower the costs, lower the environmental impact.

But that's another part of the R&D. And, finally, which this report excludes, is solar radiation management. I call it the Pinatubo strategy. It's where you put particles in the stratosphere to reflect sunlight. It's kind of a…

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