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.