Decoupling

Some environmental impacts are increasing over time, in absolute, per capita, and per dollar GDP bases, while others are decreasing, and some are increasing by some metrics and decreasing by others.

Evolution of major environmental impacts over time. For comparison, population figures are taken from the UN ¹ and GDP figures from the World Bank ². The purchasing power parity is used for GDP after 1990, and the exchange rate is used before 1990. World primary energy is from BP ³, municipal solid waste from Chen et al. ⁴, land use figures and nitrogen fertilizer from FAOSTAT ⁵, lead production from the International Lead Association ⁶, biomass, metal, and mineral figures from Krausmann et al. ⁷, CO₂ emissions from Le Quéré et al.⁸, air pollution in the OECD from the OECD ⁹, access to clean water from Ritchie and Roser ¹⁰, extreme poverty rates from Roser and Ortiz-Ospina ¹¹, methane from the World Bank ¹², ozone-depleting emissions from the World Meteorological Organization ¹³, water withdrawal from Worldometer ¹⁴, and mercury emissions from Zhang et al. ¹⁵.

All impact figures are worldwide except for NOx, CO, SOx, and VOC figures, which are reported for OECD countries. A portion of the decline of these impacts may be explained by offshoring of industry.

Some environmental impacts tend to grow, peak, and decline with rising national per-capita income. This phenomenon is known as an environmental Kuznets curve. Water pollution and localized air pollution tend to show an eventual peak of impact by wealth ¹⁶, ¹⁷, ¹⁸, but for CO₂, municipal solid waste, and biodiversity and land use, the evidence for a Kuznets curve is inconclusive ¹⁹.

Economic growth has been slowing in the United States and other wealthy countries, and overall environmental quality has come to exceed economic growth.

Source: Muller ²⁰.