Exploring global, economy-wide material trajectories and associated environmental pressures under shared socioeconomic pathways

Material production is a major contributor to many environmental challenges, but has received limited attention in the global, long-term scenarios produced by integrated assessment models (IAMs) used to investigate humankind’s potential responses. Here, we quantify economy-wide material stocks and flows for the shared socio-economic pathways (SSPs) and a low material demand scenario (LMD) using a simplified but physically consistent approach developed to the SuCCESs IAM, based on empirically observed material stock intensities of the global economy and the detailed, economy-wide stock-flow modelling of MISO2. Demand for material stocks is then translated to the material production, recycling and final waste disposal flows, parametrized from the MISO2 model. Implications for energy use, CO₂ emissions, land use and human appropriation of net primary production are quantified via the SuCCESs IAM. We find that economy-wide material stocks grow substantially in all scenarios between 2020 and 2100—from +55% in LMD, to a nine-fold increase in SSP5. Stabilization or gradual reduction of material production and related environmental pressures only occur when low economic growth is combined with strong decoupling of GDP from material stocks. Material production volumes of major materials, e.g. steel and concrete, grow in all scenarios except LMD. Without active mitigation, the environmental impacts from material production continue to increase in all but the SSP3 and LMD scenarios, in which the impacts remain stable or decline even without deliberate action to reduce them. Conversely, with moderately or strongly growing GDP and only slightly declining material stock intensity, material production would grow immensely, requiring significant effort to mitigate the related environmental pressures. Waste accumulation will continue to grow for at least several decades due to the inherent lag in material flow dynamics.

Ekholm, T., Springare, S., Savolainen, H., Streeck, J., Wiedenhofer, D. Exploring global, economy-wide material trajectories and associated environmental pressures under Shared Socioeconomic Pathways. Environmental Research Letters 21 (2026) https://doi.org/10.1088/1748-9326/ae51a9