Introduction

In 1896, a Swedish scientist, Svante Arrhenius, calculated that as a result of emissions from fossil fuel consumption, a doubling of atmospheric carbon dioxide might raise global mean temperatures by 4°C to 6°C. One hundred years after the initial calculations by Arrhenius, global warming has become the most important and controversial issue in international environmental relations. The theoretical prediction of increasing atmospheric concentrations of CO2 was first confirmed in the 1970s by measurements at Mauna Loa (Hawaii), which showed an increase from 315 ppm (parts per million) in 1958 to 331 ppm in 1975 (Pearson and Pryor 1978, p. 267). Concentrations in the preindustrial era were about 280 ppm and reached 358 ppm by 1994. Global average temperature has increased between 0.3°C and 0.6°C (0.5 to 1.1°F) over the past century. How much of this is due to natural variability and how much to human activity is not known with certainty, but the 1996 report of the Intergovernmental Panel on Climate Change (IPCC) concludes that “the balance of evidence suggests that there is a discernable human influence on global climate” (J. T. Houghton et al. 1996, p. 5), and estimates temperature increases of 2°F to 6°F over the next 100 years.

This chapter emphasizes the international aspects of curtailing global warming. Section 2 identifies some of the analytical complexities and provides factual background material.