Global Warming and Al Gore's $307 Trillion Gamble

Experts love to debate which is a better way to deal with climate change, a cap-and-trade system or carbon taxes. But there is a third option: Supercharge the global economy, and make us all as wealthy and technologically advanced as possible.

In one of its occasional assessments, the Intergovernmental Panel on Climate Change—the cowinner with Al Gore of the Nobel Peace Prize—posited a scenario in which the global economy would grow at about 2 percent a year for the next 100 years (it's growing at more than twice that pace currently) with "fragmented" and "slow" per capita economic growth and technological change.

Indeed, it is just this scenario that was used by the influential Stern Report on the economic impact of climate change. By the year 2100, the size of the global economy would be $243 trillion. However, there is another IPCC scenario. It imagines "a future world of very rapid economic growth, low global population growth that peaks in mid-century and declines thereafter, and the rapid introduction of new and more efficient technologies." According to this story line, the global economy would grow at 3.5 percent per year, giving us a $550 trillion global economy in the year 2100, more than twice the size of the economy assumed in the first scenario.

I don't know about you, but give me a century of accelerating technological change and $300 trillion to pay for it, and there are few problems that would keep me up at night. So the question is: Which policies will get us there?