An idealized model of the coupled human-technosphere-Earth system and hindcast from 1900

Integrating the human components into the Earth system framework can help fill the existing gap between the science of the natural world and society, thereby deepening our understanding of socio-environmental relationship. In the Anthropocene, these human-Earth interactions have intensified, particularly driven by the acceleration of resource-use since the Industrial Revolution. The growth of the technosphere, which refers to the global assemblage of non-food human-creations including machineries, infrastructure, and buildings, has played a central mechanistic role in this acceleration.

Here, we present an idealized model to couple the dynamics of the technosphere with other Earth spheres and to capture its interaction with human activities. The key driver of the numerical model is a dynamic time allocation of the human population to food provision, technosphere construction, or services, based on a competition of state-dependent motivations. The products of the activities computed from the labour and efficiency, together with Earth system feedbacks, thereby impact the motivations during the next time step. The mass of the technosphere contributes to the efficiency of human activities. We compare model outputs with historical data and find that the simulation reproduces trends in the global food supply, technosphere mass accumulation, and their feedback on the change of the sectoral labour distribution since 1900. The study establishes a novel integrated framework for advancing systemic human–Earth coupling, paving the way for country-level and grid-scale analyses in the future.