Introduction

Climate change is so fundamental a challenge that it may be best addressed from a multiple of perspectives, using a multiple of approaches.

This is a radically different concept from the arrangement developed thus far. Under the Kyoto Protocol, emission reduction obligations apply to entire economies, not to individual sectors; reforestation (which sequesters and therefore removes carbon dioxide or CO2 from the atmosphere) is allowed to substitute for abatement (which reduces greenhouse gas [GHG] additions to the atmosphere, relative to “business as usual”); the emissions of different countries can be traded; and increases in the emission of one gas can be offset by reductions in the emission of another. This approach has one great virtue: it promotes cost-effective abatement.

Unfortunately, this approach has also (so far, at least) failed to address the more important objective, which is to reduce GHG emissions and ultimately to stabilize atmospheric concentrations. There may be different explanations for this. My diagnosis is that this failure is due to a lack of robust enforcement. So, why not add an enforcement capability? As I shall explain in this chapter, it may not be possible to enforce the current treaty design. If enforcement is important—and I shall argue here that it is essential—then a better strategy may be to break up the problem, treating different sources and types of gases separately. This strategy may succeed better at reducing emissions overall.