As the world’s second most consumed resource, sand is being depleted at an alarming rate. China accounted for nearly half of the world’s sand consumption in 2012. Here we present a material flow... Show moreAs the world’s second most consumed resource, sand is being depleted at an alarming rate. China accounted for nearly half of the world’s sand consumption in 2012. Here we present a material flow analysis of sand from 1995 to 2020 that shows China’s overall sand supply surged by approximately 400% over the study period, yet the proportion of natural sand dropped from ~80% to ~21% due to the increasing use of manufactured sand. From 2010 to 2020, China’s natural sand supply nearly halved due to the strict policies on natural sand mining and the promotion of manufactured sand. This shift demonstrates a possibility for mitigating impacts on natural sand resources during industrialization and urbanization. Show less
Creutzig, F.; Simoes, S. G.; Leipold, S.; Berrill, P.; Azevedo, I.; Edelenbosch, O.; ... ; Wilson, C. 2024
As fossil fuels are phased out in favour of renewable energy, electric cars and other low-carbon technologies, the future clean energy system is likely to require less overall mining than the... Show moreAs fossil fuels are phased out in favour of renewable energy, electric cars and other low-carbon technologies, the future clean energy system is likely to require less overall mining than the current fossil-fuelled system. However, material extraction and waste flows, new infrastructure development, land-use change, and the provision of new types of goods and services associated with decarbonization will produce social and environmental pressures at localized to regional scales. Demand-side solutions can achieve the important outcome of reducing both the scale of the climate challenge and material resource requirements. Interdisciplinary systems modelling and analysis are needed to identify opportunities and trade-offs for demand-led mitigation strategies that explicitly consider planetary boundaries associated with Earth’s material resources. Show less
Fishman, T.; Mastrucci, A.; Peled, Y.; Saxe, S.; Ruijven, B. van 2024
The construction materials used in buildings have large and growing implications for global material flows and emissions. Material Intensity (MI) is a metric that measures the mass of construction... Show moreThe construction materials used in buildings have large and growing implications for global material flows and emissions. Material Intensity (MI) is a metric that measures the mass of construction materials per unit of a building’s floor area. MIs are used to model buildings’ materials and assess their resource use and environmental performance, critical to global climate commitments. However, MI data availability and quality are inconsistent, incomparable, and limited, especially for regions in the Global South. To address these challenges, we present the Regional Assessment of buildings’ Material Intensities (RASMI), a new dataset and accompanying method of comprehensive and consistent representative MI value ranges that embody the variability inherent in buildings. RASMI consists of 3072 MI ranges for 8 construction materials in 12 building structure and function types across 32 regions covering the entire world. The dataset is reproducible, traceable, and updatable, using synthetic data when required. It can be used for estimating historical and future material flows and emissions, assessing demolition waste and at-risk stocks, and evaluating urban mining potentials. Show less
Sun, X.; Hao, H.; Galeazzi, C.; Fishman, T.; Xun, D.; Ericsson, M.; ... ; Zhao, F. 2024
Existing research on the security of the supply of critical materials for clean energy generally aggregates information at the country level, a practice that obscures the extensive role of foreign... Show moreExisting research on the security of the supply of critical materials for clean energy generally aggregates information at the country level, a practice that obscures the extensive role of foreign direct investment (FDI) in the production of critical materials. FDI refers to an ownership stake in a company or project by an overseas investor. Here we establish a database for global mining of lithium, cobalt, nickel and platinum at company level, covering 240 countries and regions. We show that 47% of lithium, 71% of cobalt, 41% of nickel and 34% of platinum mined in 2019 were under FDI. We then explore how FDI may affect supply risks by proposing a supply risk index that allocates production of the critical materials to the country of origin of investors instead of the country where production is located. We present upper and lower bounds of the supply risk index that reflect scenarios where either all investors or only state investors prioritize the home-country demand, respectively. This study presents an approach for assessing the national supply risks of critical materials, considering the geographical allocation of FDI. Show less
The growing dependence of society on rare-earth elements poses a challenge to achieving a just low-carbon transition globally. While circular economy strategies have gained attention, their... Show moreThe growing dependence of society on rare-earth elements poses a challenge to achieving a just low-carbon transition globally. While circular economy strategies have gained attention, their specific impacts remain unmeasured. Here we present an integrated model that quantifies how circular economy strategies can reshape global supply chains of the critical rare-earth elements such as neodymium, praseodymium, dysprosium and terbium. The model considers both in-ground and in-use stocks across ten regions from 2021 to 2050. The projections include the full deployment of three widely accepted climate scenarios. We find a considerable mismatch between in-ground stocks, supply and demand at specific region and element levels, with the mismatch for heavy rare-earth elements as a key obstacle for achieving net-zero emissions targets. We suggest that, as in-ground stocks decline among mineral suppliers, the accumulation of in-use stocks in consuming regions can foster a more balanced and less polarized geopolitical landscape for rare-earth elements, and circular economy strategies can lead to an increase of 701 kt secondary supply and a decrease of 2,306 kt demand within the next three decades. Implementing these circular economy strategies will require international cooperation in the governance of rare-earth elements amid sustainable transition. Show less
Suburban sprawl emerged during the 20th century alongside the widespread ownership of cars. This type of low-density housing generates enduring car dependency due to the long lifetimes of buildings... Show moreSuburban sprawl emerged during the 20th century alongside the widespread ownership of cars. This type of low-density housing generates enduring car dependency due to the long lifetimes of buildings. A more sustainable mobility system would require a deep transformation to densify urban forms and thus foster proximity of homes, work, and services. Here we explore the evolution of long-lived residential building stocks and the potential for breaking of this lock-in by selective demolishing of detached houses to densify urban forms. We assess impacts on land use, material demand and stocks, and greenhouse gas emissions. We use a novel dynamic, Material Flow Analysis (MFA) model applied to a Swedish case study that accounts for the co-relations of building stock and car fleets through residential density. The model includes different municipality types and we explore three different speeds for the change in urban form. An accelerated densification requires more bulk materials in construction but fewer scarcer materials in cars. However, the up-front emissions of accelerated densification construction are only compensated by mobility savings in the long-term, by 2100. Emissions trends for the three scenarios are far from the urgent decarbonisation necessary. However, the denser final built environments may have social benefits and can free up significant land. Show less
Engelenburg, M. van; Deetman, S.P.; Fishman, T.; Behrens, P.A.; Voet, E. van der 2024
Construction materials are associated with significant environmental and resource impacts. The circular use of materials already in use as stocks may provide an opportunity to reduce these impacts.... Show moreConstruction materials are associated with significant environmental and resource impacts. The circular use of materials already in use as stocks may provide an opportunity to reduce these impacts. We provide a dataset describing the potential global urban mine consisting of transportation infrastructure in an open database based on geospatial data from OpenStreetMaps. We reveal the significant opportunities of the embedded materials in this huge stock. With this Total Resources in Physical Infrastructure, or TRIPI, the database we provide easy access to a global dataset covering 175 countries and sub-regions, allowing researchers to select an area of study, and find the location as well as the material composition of the physical infrastructure. Material stocks are reported on a national level and commonly used regional aggregations. Material stocks are reported per kg, kg per capita, and kg per area; and for the physical type of infrastructure that is available in kilometres and area (km2). This dataset can be used in various research applications such as Material Flow Analysis, Material stock inventories, Country-level comparisons of infrastructure density, and others, and inform policy on harnessing the opportunities of the urban mine. Show less
The foundations of today’s societies are provided by manufactured capital accumulation driven by investment decisions through time. Reconceiving how the manufactured assets are harnessed in the... Show moreThe foundations of today’s societies are provided by manufactured capital accumulation driven by investment decisions through time. Reconceiving how the manufactured assets are harnessed in the production–consumption system is at the heart of the paradigm shifts necessary for long-term sustainability. Our research integrates 50 years of economic and environmental data to provide the global legacy environmental footprint (LEF) and unveil the historical material extractions, greenhouse gas emissions, and health impacts accrued in today’s manufactured capital. We show that between 1995 and 2019, global LEF growth outpaced GDP and population growth, and the current high level of national capital stocks has been heavily relying on global supply chains in metals. The LEF shows a larger or growing gap between developed economies (DEs) and less-developed economies (LDEs) while economic returns from global asset supply chains disproportionately flow to DEs, resulting in a double burden for LDEs. Our results show that ensuring best practice in asset production while prioritizing well-being outcomes is essential in addressing global inequalities and protecting the environment. Achieving this requires a paradigm shift in sustainability science and policy, as well as in green finance decision-making, to move beyond the focus on the resource use and emissions of daily operations of the assets and instead take into account the long-term environmental footprints of capital accumulation. Show less
Recent research suggests that over 75% of resources extracted globally now go toward creating, maintaining, or operating material stocks (MS) to provide societal services like housing, transport,... Show moreRecent research suggests that over 75% of resources extracted globally now go toward creating, maintaining, or operating material stocks (MS) to provide societal services like housing, transport, education, and health. However, the integrity of current and future built environments, and the capacity of the system to continue providing services, are threatened by extreme events and sea-level rise (SLR). This is especially significant for the most disaster-prone countries in the world: Small Island Developing States. In the aftermath of disasters, complex rebuilding efforts require substantial material and economic resources, oftentimes incurring massive debt. Understanding the composition and dynamics of MS and environmental threats is essential for current and future sustainable development. Drawing on open-source OpenStreetMap (OSM) data, we conducted a spatially explicit material stock analysis (MSA) for The Bahamas for 2021, where we included buildings and transport MS, and SLR exposure scenarios. Total MS was estimated at 76 million tonnes (Mt) or 191 tonnes per capita (t/cap) of which transport comprises 43%. These MS are likely to increase by 36 Mt in the future. Simulations show that under 1-, 2-, or 3-m SLR scenarios, around 4, 6, and 9 Mt of current MS will be exposed, with transport MS at greatest risk, with over 80% of total exposure in each scenario. Our findings highlight the critical role that key MS play in sustainability and resilience, contributing to the emphasis on effective development planning and climate change adaptation strategies, and to the exploration of the use of OSM data for studying these objectives. Show less
Martin del Campo, F.; Singh, S.J.; Fishman, T.; Thomas, A.; Noll, D.; Drescher, M. 2023
Resource-use patterns may entail systemic risks and cascade effects, which consequently inhibit the ability to deliver socioeconomic services. Identifying resource-use patterns exhibiting systemic... Show moreResource-use patterns may entail systemic risks and cascade effects, which consequently inhibit the ability to deliver socioeconomic services. Identifying resource-use patterns exhibiting systemic risks and reshaping their combinations is a potential lever in realizing the transition to a sustainable, resilient, and resource-secure system. Using an island context to assess the quantity and composition of resource throughput enables a more comprehensive analysis of these risks. This article presents the first mass-balance account of socio-metabolic flows for The Bahamas in 2018, to identify socio-metabolic risks and cascading effects. Socio-metabolic risks are systemic risks related to critical resource availability, material circulation integrity, and (in)equities in cost and benefit distributions. We utilize the economy-wide material flow accounting framework to map the material flow patterns across the economy. In 2018, annual direct material input was estimated at 9.4 t/cap/yr, of which 60% were imports. High masses of waste (1.4 t/cap/yr) remained unrecovered due to the lack of recycling. Total domestic extraction (DE) were dominated by non-metallic minerals with more than 80%, while marine biomass makes up barely 1% of total DE. Due to its linear, undiversified metabolism, and heavy imports dependency, the system is susceptible to socio-metabolic risks and cascading effects including low levels of self-sufficiency, high vulnerability to shocks, commodity price fluctuations, threats to sensitive ecosystems, health impacts, and economic losses, among others. A holistic resource management strategy and nature-based solutions that consider the trade-offs and synergies between different resource-use patterns are critical when exploring potential plans for metabolic risk reduction. Show less
Nguyen, T.C.; Miatto, A.; Fishman, T.; Kim, J. 2023
An efficient transport infrastructure not only connects markets and people but also positively affects economic activity, development, and growth. However, little research acknowledges the... Show moreAn efficient transport infrastructure not only connects markets and people but also positively affects economic activity, development, and growth. However, little research acknowledges the interaction between the material resources of in-use stocks of transport infrastructure and their service provision. Using the European transport sector as a case study, we quantify the mass of materials composing the transport infrastructure and analyze the interactions between in-use stocks and service provision through the stock-service productivity indicator. We also assess the primary factors driving stock-service productivity changes and explore feasible ways to improve productivity. To do so, we decompose changes in stock-service productivity to the effects of transport intensity, affluence, population density, road density, and material stock efficiency at regional and national levels based on the Log-Mean Divisia Index (LMDI) method. The results indicate that (1) the productivity of the materials stocked in the European road infrastructure increased from 51 to 57 freight-kilometers/ton-year during the 2010–2019 period; (2) freight transport intensity and affluence were the dominant driving factors in both regional and national scales, while population density, road density and material efficiency played smaller roles. This study contributes to understanding the deeper relation between resource use and its provided services. Show less
Ewijk, S. van; Ashton, W.S.; Berrill, P.; Cao, Z.; Chertow, M.; Chopra, S.S.; ... ; Myers, R.J. 2023
The circular economy has become a useful concept in sustainable resource management and an area of research that influences business and policy. The successful application of the circular economy... Show moreThe circular economy has become a useful concept in sustainable resource management and an area of research that influences business and policy. The successful application of the circular economy benefits from extensive engagement with the body of scientific knowledge that brought it about, and which offers many relevant methods and findings. This white paper promotes such engagement by presenting 10 insights from the field of industrial ecology; each insight presents critical concepts, challenges, or opportunities for the circular economy stakeholders. Show less
The largest outputs of rare earth mining are the low-value byproducts cerium and lanthanum, which burden rare earth supply chains because they must be separated from more desirable rare earths used... Show moreThe largest outputs of rare earth mining are the low-value byproducts cerium and lanthanum, which burden rare earth supply chains because they must be separated from more desirable rare earths used in magnet production. Promoting demand for cerium and lanthanum can potentially diversify the economics of rare earth mining and improve supply chain stability for all rare earth elements. A promising avenue for increasing byproduct rare earth element demand is their use in aluminum alloys; an application for cerium and lanthanum offering multiple benefits to manufacturing such as energy reduction and improved throughput. Experimental materials science and economic implications of Al-rare earth element alloys will be discussed. We show that Al–La/Ce alloys have elevated mechanical strength compared to more traditional aluminum alloys, in some formulations can be used without heat treatment, and possess a highly castable eutectic microstructure. This report presents the use of cerium and lanthanum in aluminum alloys as an example of how supply chain focused approaches to technological development can benefit stakeholders at every step in production. Show less
Improving resource efficiency (RE) is an important objective of the Sustainable Development Goals. In this study we find a strong exponential relationship between economic complexity index (ECI)... Show moreImproving resource efficiency (RE) is an important objective of the Sustainable Development Goals. In this study we find a strong exponential relationship between economic complexity index (ECI) and RE of countries. ECI measures the level of accumulated knowledge of a society enabling the products it makes. The relationship between ECI and RE is stronger for primary material importers and countries with stable institutions. Assessing a country's level of ECI also allows the outlook of future RE trends. We explain how ECI influences RE at the product level by establishing the product space for each country and by defining core products that contribute to a high product complexity index, high RE (i.e., unit price) and promising expansibility (i.e., core number), which indicates the potential to produce more advanced products in the future. Policies that improve economic complexity and invest in core products seem to be a priority to achieve sustainable development. Show less
