Population, Ecological Footprint and the Sustainable Development Goals.

The Anthropocene can be read as being the era when the demand humanity makes on the biosphere's goods and services-humanity's 'ecological footprint'-vastly exceeds its ability to supply it on a sustainable basis. Because the 'ecological' gap is met by a diminution of the biosphere, the inequality is increasing. We deploy estimates of the ecological gap, global GDP and its growth rates in recent years, and the rate at which natural capital has declined, to study three questions: (1) at what rate must efficiency at which Nature's services are converted into GDP rise if the UN's Sustainable Development Goals for year 2030 are to be sustainable; (2) what would a sustainable figure for world population be if global living standard is to be maintained at an acceptably high level? (3) What living standard could we aspire to if world population was to attain the UN's near lower-end projection for 2100 of 9 billion? While we take a global perspective, the reasoning we deploy may also be applied on a smaller scale. The base year we adopt for our computations is the pre-pandemic 2019.