Summary The international industrial ecology (IE) research community and United Nations (UN) Environment have, for the first time, agreed on an authoritative and comprehensive data set for global material extraction and trade covering 40 years of global economic activity and natural resource use. This new data set is becoming the standard information source for decision making at the UN in the context of the post‐2015 development agenda, which acknowledges the strong links between sustainable natural resource management, economic prosperity, and human well‐being. Only if economic growth and human development can become substantially decoupled from accelerating material use, waste, and emissions can the tensions inherent in the Sustainable Development Goals be resolved and inclusive human development be achieved. In this paper, we summarize the key findings of the assessment study to make the IE research community aware of this new global research resource. The global results show a massive increase in materials extraction from 22 billion tonnes (Bt) in 1970 to 70 Bt in 2010, and an acceleration in material extraction since 2000. This acceleration has occurred at a time when global population growth has slowed and global economic growth has stalled. The global surge in material extraction has been driven by growing wealth and consumption and accelerating trade. A material footprint perspective shows that demand for materials has grown even in the wealthiest parts of the world. Low‐income countries have benefited least from growing global resource availability and have continued to deliver primary materials to high‐income countries while experiencing few improvements in their domestic material living standards. Material efficiency, the amount of primary materials required per unit of economic activity, has declined since around 2000 because of a shift of global production from very material‐efficient economies to less‐efficient ones. This global trend of recoupling economic activity with material use, driven by industrialization and urbanization in the global South, most notably Asia, has negative impacts on a suite of environmental and social issues, including natural resource depletion, climate change, loss of biodiversity, and uneven economic development. This research is a good example of the IE research community providing information for evidence‐based policy making on the global stage and testament to the growing importance of IE research in achieving global sustainable development.

The growing extraction of natural resources and the waste and emissions resulting from their use are directly or indirectly responsible for humanity approaching or even surpassing critical planetary boundaries. A sound knowledge base of society's metabolism, i.e., the physical exchange processes between society and its natural environment and the production and consumption processes involved, is essential to develop strategies for more sustainable resource use. Economy-wide material flow accounting (MFA) is a framework that provides consistent compilations of the material inputs to national economies, changes in material stocks within the economic system, and material outputs to other economies and the environment. We present the conceptual foundations of MFA and derived indicators and review the current state of knowledge of global patterns and trends of extraction, trade, and use of materials. We discuss the relation of material use and economic development and the decoupling of material use from economic growth in the context of sustainable resource use policies.

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Recent years have seen a growing interest in the potential for a more circular economy and the application of material flow accounting to increase the knowledge base on materials accumulating in in-use stocks. This study assesses the dynamics of stocks and flows related to road networks, which are an important destination for recycled construction and demolition waste.To assess the requirements of construction minerals of the road network in the United States we develop a bottom-up stock driven model to assess long-term inflows, outflows, and materials accumulated in roads. We estimate material requirements using the expansion of the transport network as a driver, and scheduled maintenance and technological coefficients from engineering literature to assess input and output flows. We apply the model to historical data for the United States road network from 1905-2015. We show that the current material stock of construction minerals in the road network of the United States is 15.1 billion tonnes, growing 21-fold since 1905.During the 20 th century, the material requirements of road construction have declined from 35% to 15% of economy-wide material consumption of non-metallic minerals in the United States. The share of roads in economy-wide in-use stocks has also declined from 17% to 13%. This shows that roads, once established, remain in place and the majority of material flows are due to extending and refurbishing them, while the construction of completely new roads make up a much smaller part of the material flows due to the road network.

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