?People, planet and prosperity?: The determinants of humanity's environmental footprint

Environmental or 'ecological' footprints have been widely used in recent years as indicators of resource consumption and waste absorption on the basis of biologically productive land area required per capita with prevailing technology. Such footprints represent a partial measure of the extent to which the planet, its regions, or nations are moving along a sustainable development pathway. They vary between countries at different stages of economic development and varying geographic characteristics. The determinants of environmental footprints in some 113 countries from around the world have been evaluated. Dimensional analysis techniques from engineering and the physical sciences are employed to determine the relative significance of population density, economic wealth, and intensity of pollutant emission. Variations about the resulting 'power-law' correlation suggest the extent to which individual nations are currently frugal or profligate in terms of their resource use and environmental impacts. The scatter associated with footprints, or closely related parameters, also indicates the uncertainty inherent within the international datasets needed to compute them, as well as differences in local climate and terrain. Nevertheless, national footprints alert humanity to the necessity of living within the regenerative capacity of the biosphere in order to ensure 'environmental sustainability'.