While it may seem that science contributes only marginally to international law, it was in fact a scientist, Garrett Hardin, who proposed a framework four decades ago that illuminates most of the international policy issues of climate change. Hardin's widely cited 1968 article, "The Tragedy of the Commons," is much more than a description of the inevitable destruction of public, unregulated, and finite resources, a phenomenon well-known since ancient times. It also offers insights into how one might manage such resources and suggests an ethical approach relevant to the difficult problems of international responses to climate change. Anthropogenic climate change epitomizes the subtitle of Hardin's article: "The population problem has no technical solution; it requires a fundamental extension of morality." This subtitle was inspired by an earlier and equally influential article on the control of nuclear weapons by Jerome Wiesner and Herbert York, who admit the limitations of purely scientific or technical modes of thinking in regards to today's changing world. In other words, the global climate challenge is an intractable international commons issue that requires an international framework through which an economically feasible solution can be created.
The World's Climate Commons Economy
Before discussing viable solutions, it is first important to establish today's current climate crisis, which is mainly focused around the energy resource question. Energy is a necessary ingredient of all activity of every kind and can be regarded as the primary physical basis of an economy. The fundamental and pervasive role of energy in the economy virtually guarantees that societies will exploit the least expensive means of producing it in facilities such as stationary power plants or petroleum refineries. These facilities manufacture energy media, such as electricity, gasoline, or hydrogen that are transportable and easily converted to useful work in an endless variety of devices and processes. For nearly two centuries, fossil fuels have been the cheapest source of energy for large-scale economic activity, and their use is growing at an unprecedented pace. However, various market inefficiencies exist that inhibit the most efficient technologies for these end uses. Depending on the perceived benefit from doing so, governments typically intervene through regulation, taxation, or incentives to drive behavior toward greater end-use efficiency.
In the long run, reducing greenhouse gas emissions requires changing the technologies for energy production and use. Reducing or eliminating the need for fossil-fueled energy could be the means through which this long run consequence could be achieved. It is also possible to increase the capacity of the biosphere to absorb C[O.sub.2] through reforestation and other land-management practices, but this will always be less important than the primary goal of reducing emissions. Because efficient use and C[O.sub.2],-free production of energy are technical matters, it seems logical that the challenge of global climate change should boil down to a question of adjusting the technological basis of the energy economy.
The record of atmospheric chemistry over time hints at the magnitude of this challenge. Atmospheric CO, began to increase significantly as the Industrial Revolution gathered momentum early in the nineteenth century. Coal was the fuel that freed powered machinery from the constraints of wind or water driven mills. Petroleum and natural gas came later, and much of the energy for today's world economy-- about 85 percent--comes from fossil fuels. The scale of the human behaviors contributing to unwanted atmospheric C[O.sub.2] is the scale of the world economy. The technologies in question range from large stationary power sources to widely dispersed end-uses in manufacturing, transportation, agriculture, and domestic applications. …