New study warns of potential rapid global population decline due to environmental crises

A new study published in the scientific journal Chaos, Solitons & Fractals offers a unified mathematical equation to describe 12,000 years of human population growth, raising concerns about potential future scenarios if global environmental crises intensify.

The research, co-authored by a researcher and the late Kostya Trachenko of Queen Mary University of London, presents a non-linear rate-feedback model for global population increase. This framework, initially developed within the physics of amorphous materials like glass, successfully reproduces key patterns of population evolution from the Neolithic era to the present day. Unlike traditional demographic models that assume exponential or logistic growth, this new approach allows for natural transitions between different historical regimes using a single parameter.

The model revisits a 1960 prediction by Heinz von Foerster and colleagues, who calculated that the global population would tend toward infinity around 2026. While humanity avoided this specific scenario due to falling fertility rates, the new study suggests that the underlying mathematical dynamics could re-emerge under certain conditions. Researchers validated the equation, known as the Trachenko-Zakone equation, against empirical data from various historical periods, finding it accurately replicated phases of rapid exponential growth, such as during the industrial era, and the slower 'stretched exponential' phase characterizing global population growth since 1970.

According to the analysis, current global trends are not leading to a catastrophic 'singularity' as predicted by von Foerster, as the key parameter remains in a stabilizing regime. However, the model explores the consequences of severe environmental crises drastically reducing the planet's carrying capacity due to climate collapse, pandemics, conflicts, or resource scarcity. In a conservative hypothetical scenario where Earth's sustainable carrying capacity is reduced to 2 billion people, the model predicts a rapid global population decline, potentially halving the human population by approximately 2064.

The authors emphasize that this is not a prediction but a mathematical illustration of how sensitive population dynamics can be to abrupt environmental or social changes. The current trajectory, the study concludes, remains stable and does not indicate imminent collapse.