What, then, should we do? Greenhouse gases are the byproduct of activities that we value—but we have discovered in the last decade or two that there's a negative byproduct from those activities: the emission of carbon dioxide and methane. The favorite solution of economists is to tax the offending activity. Therefore, if we are imposing a social cost on the world by producing greenhouse-gas emissions, we should impose a charge for that social cost. A tax on greenhouse emissions would discourage such emissions except where it's socially worthwhile.

The second advantage to an emissions tax is that it would generate revenues for government. All countries need more revenue. However, although the imposition of a carbon tax would be easy to monitor, the enforcement of the tax would be more difficult. That is not an insurmountable barrier, however, because the International Monetary Fund, which monitors the fiscal conditions of most countries, could also be charged to monitor whether countries were collecting revenues corresponding to the volume of their emissions.

As attempted by the Clinton administration and the European Union, says Cooper, the experience to date with introducing an emissions tax is not great. However, if we are serious about reducing greenhouse-gas emissions, raising the price of "emitting activities" is necessary in order to encourage large-scale conservation.

The imposition of carbon taxes need not result in increased revenues for governments, Cooper adds: if we adopted such a tax, we could make a comparable reduction in another tax. States Cooper, "My advice to you is to think taxes. And if you don't like taxes, learn to live in a warmer climate."