Growth and sustainability in a material world: the self-reinforcing cycle of population, GDP and resource use

The goal of this chapter is a macro-scale discussion of growth: human, economic and material, and the positive feedback links between these macro elements. A sustainability transition, we argue, must address the full spectrum of these macro forces, and do so with the awareness of the historical forces that have shaped them. We represent human society as feedback loops between economic activity (as measured by gross domestic product), human population, and social metabolism (measured as physical flows). The nodes of this triangle are mutually reinforcing: economic growth is in part driven by population growth, larger populations require more resources, more resource use enables greater economic investment and activity. We analyse these feedbacks quantitatively, globally and on regional levels. We find that the self-reinforcing power of these relations has gradually become weaker. If the system is not as self-amplifying any more, it equally might not be as self-diminishing. Thus, for high-income countries, no-/low-economic growth may no longer represent a systemic threat. However, for them, the issue at stake is higher: the departure from their high fossil fuel use, as well as a reduction in the use of material resources, is not a matter of no/low growth, but of substantial degrowth, at least biophysically. Globally speaking the current development model is extremely unsustainable, and probably many of those on the way will now be able to successfully achieve their goals because of global environmental and economic feedbacks.