Climate change and optimum optimum population

Abstract

This paper is a contribution to the debate over optimum human population. It is argued that the usual arguments for a reduction in instantaneous population size as beneficial for climate change are flawed because they focus on the emissions rate rather than on cumulative emissions. Cumulative emissions, in turn, are shown to be the key factor in determining peak warming. A simple model is introduced to illustrate how population spreading (reducing instantaneous population size while increasing the timeframe over which lives are spread) would not affect cumulative emissions and hence, given a causal link between cumulative emissions and peak warming, would not help with climate change. Two possible reasons to doubt the assumptions of the model are surveyed and dismissed, and a third possible reason (related to the effect of population size on technical progress in mitigation and adaptation) is also discussed. – AI-generated abstract.