This comparative analysis shows that population size and affluence are the principal drivers of anthropogenic
environmental stressors, while other widely postulated drivers (e.g. urbanization, economic structure,
age distribution) have little effect. Similarly, increased education and life expectancy do not increase environmental stressors, suggesting that some aspects of human well-being can be improved with minimal environmental impact. Projecting to 2015, we suggest that increases in population and affluence will likely
expand human impact on the environment by over one-third. Countering these driving forces would require
increases in the efficiency of resource use of about 2% per year.

Author Keywords: ecological footprint, STIRPAT, IPAT, enrivonmental stressors, environmental impact, population, urbanization