Recent research in economics shows how not to design climate treaties—and suggests how to get it right.

Robert Stavins argues for an economic approach to solving environmental problems and explains why "environmental economics" is not an oxymoron.

The United States has considerable tax administration and cap-and-trade expertise that could highlight potentially successful carbon pricing approaches. Although this experience is not climate-related, the United States deploys an efficient and highly compliant excise tax system, and it could assist developing country efforts to build their own capacity to tax carbon. The United States also has long experience with cap-and-trade systems for criteria air pollutants, much of which is transferable to greenhouse-gas emissions trading.

The Kyoto Protocol establishes a very complex and ambitious regime, in architecture if not stringency. The problem is that relatively few states, representing only about a quarter of the world's emissions, have been willing to assume emission targets under Kyoto....The future of the Protocol thus seems doubtful at best. Even in the most optimistic scenario, a new round of emissions targets couldn't be agreed in time to prevent a legal gap between the first and second commitment periods. A possible middle ground would be to establish a transitional regime that would be political in nature, but that could evolve over time into a legally-binding regime.

An effective international climate agreement poses formidable challenges. Existing agreements, naturally, have some good features. Further improvements are being discussed in the current negotiations. But the cost and uncertainty associated with regular renegotiation of commitments is not being addressed. The São Paulo Proposal suggests mechanisms that would avoid the need for regular renegotiation of commitments and suggests other ways to make international climate agreements more effective.

Our proposal for a post-2012 international global climate policy agreement contains three essential elements: meaningful involvement by key industrialized and developing nations; an emphasis on an extended time path of targets; and inclusion of market-based policy instruments. This architecture is consistent with fundamental aspects of the science, economics, and politics of global climate change.

A climate treaty is characterized by a large number of parameters: What should the abatement or emission levels be? How should the burden to abate be distributed across countries? What should the time profile for the emission levels be? Should there be issue linkages with other policy areas? Should there be any side transfers between some countries and, if so, what should the transfers be? This richness in parameters implies that there is a lot to decide and negotiate before the final climate treaty is ready.

Moreover, there is great uncertainty regarding the future costs and benefits of abatement. Today, it is not yet known how much abatement will be desirable in the future. This means that any climate treaty must be updated, or renegotiated, quite frequently in the coming years. The realized climate policies depend on future international negotiations—and the rules governing these.

An effective policy approach to climate change would be a global emission trading system. Opinions differ, however, as to what approach should be pursued when fostering a global emissions trading system. Many argue in favor of linking various national and regional emission trading systems as a possible way forward. However, an alternative method, which involves developing a new system from the ground up, could prove more advantageous. Under an Upstream Global Emission Trading System (UGETS), all nations would use an upstream emissions trading system that would result in far fewer monitoring points than a downstream system. A nation would only need to keep track of domestic shipments and imports of fossil fuels.