The role of socio‐economic material stocks for natural resource use in the United States of America from 1870 to 2100

Abstract

Globally, more than half of all extracted materials are used to build and maintain material stocks. The United States of America (USA) is one of the largest global consumers of these materials. To assess the role of stocks for long‐term material use in an affluent industrialized economy, we present an analysis of material use and stock accumulation for the USA from 1870 to 2100. On the basis of the dynamics of stocks and resulting end‐of‐life (EoL) outflows, we investigate stock‐building material demand, waste management, and circular economy potentials and present two prospective scenarios until 2100 to highlight the long‐term effect of stock‐flow dynamics. From 1870 to 2017, we found continuous stock growth, which strongly decelerated after the 2007 crisis. Overall, 40% of historical domestic material consumption was used to build and maintain stocks. EoL outflows from stocks increased until 2017, about half of which were discarded as final waste. In both prospective scenarios to 2100, stock build‐up and maintenance require material inputs larger than those used over the whole historical period. Stabilizing stocks near the current level could mitigate 23% of material demand compared to a return to pre‐2007 stock growth. Stabilized stocks also result in stable EoL outflows after 2050, whereas ongoing stock growth makes outflows grow until 2080. Increased recycling of these EoL outflows could potentially cover for large parts of material requirements for maintaining stable future stocks. Limiting demand for stocks and increasing recycling will require targeted demand‐side policies, adjustments to EoL management, and the establishment of recycling industries within the USA. This article met the requirements for a gold–gold JIE data openness badge described at http://jie.click/badges.

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