ABSTRACT
Decoupling or delinking, that is, improvements in environmental/resource indicators with respect to economic activity indicators, is increasingly used to evaluate progress in the use/conservation of natural and environmental resources. The Organization for Economic Co-operation and Development is doing extensive work on decoupling indicators for reporting and policy evaluation purposes (OECD 2002). Various decoupling or resource efficiency indicators are included in the
European Environment Agency’s state-of-the-environment reports (EEA 2003a, b, c), and a few European countries started to include indicators of delinking in official analyses of environmental performance (DEFRA/DTI 2003). Some countries are considering the inclusion of delinking targets in their major environmental policies, and the US has adopted an emissions-intensity target in its climate policy. Delinking trends in industrial materials and energy have been scrutinized
in the advanced countries for several decades.1 In the 1990s, research on delinking was extended to include air pollution and greenhouse gas (GHG) emissions, including proposals for some stylized facts on the relationship between pollution and economic growth, which are encompassed in the environmental Kuznets curve (EKC), so called because of the similarity with Kuznets’s (1955) suggestions about long-run income distribution paths.2 The EKC hypothesis, which is the natural extension of delinking analysis, is that, for many pollutants, there is an inverted U-shaped relationship between per capita income and pollution. This hypothesis does not stems from a theoretical model, but arises from conceptual intuition, although some recent contributions show the extent to which the environmental Kuznets hypothesis may be included in formalized economic models.3 Despite increasing applied research, empirical evidence on emissions EKC remains ambiguous. Some pollutants, mainly those identified as having a regional/local impact, seem to show a turning point (TP) at certain levels of income; but there is a degree of consensus that some critical externalities, such as carbon dioxide (CO2) emissions and waste flows, rise monotonically with income. At best, a relative delinking may take place (Stern 2004).4
