ABSTRACT
As we move deeper into the Anthropocene, it has become increasingly clear that the Earth itself is a complex system subject to use and abuse as a consequence of a wide range of human activities. (Steffen et al. 2004). This system has many of the attributes we associate with the idea of the commons. For the most part, the principal elements of the system are open to entry on the part of human users; uncoordinated human uses can produce harmful impacts at the systemic level. The system lacks effective protection against the side effects or unintended consequences of human activities launched in pursuit of a variety of goals. As is the case with other commons, humans can take steps to introduce cooperative arrangements to protect various elements of the Earth system from the impacts of anthropogenic activities. By almost any measure, for example, the effort to protect the stratospheric ozone layer through the introduction and progressive strengthening of the 1987 Montreal Protocol on Substances that Deplete the Ozone Layer has been a success (Parson 2003). Yet this is an exceptional case. Most elements of the Earth system (e.g. the climate system, the planet’s biological endowment, the nitrogen cycle, the open oceans beyond the limits of national jurisdiction) lack effective governance systems designed to protect them from the impacts of a wide range of human activities.
