Projecting future human demand on the Earth's regenerative capacity

The Ecological Footprint measures human demand for ecological goods and services, converting various consumption activities into an area of world average bioproductive land measured in global hectares. This may then be compared to an area that indicates the ability of Earth's ecosystems to support that consumption (biocapacity). Ecological Footprint analyses have generally focused on past and present levels of impact, as the Footprint is not in itself a predictive tool. However, it is equally possible to conduct an Ecological Footprint analysis from projections of future ecosystem productivity and consumption levels. Here we use a Footprint Scenario Calculator to convert projected consumption and emission quantities into Ecological Footprint and biocapacity trends up to 2050. This Calculator uses a variety of parameters as input, ranging from food demand to CO2 emissions. Both baseline projections and alternative scenarios have been built and compared to assess the possible effects of various courses of action. We found that, under widely accepted consumption projections, by 2050 humanity will be using resources and producing wastes at 2.6 times the rate at which they can be renewed or sequestered. The simplistic analysis performed here has the potential to educate and illustrate potential inconsistencies in the various demand projections performed by organizations. However, to have relevance at a national level, more sophisticated models are required. The most likely framework for such models is based upon Environmentally Extended Input Output analyses; these models have huge potential if true dynamism with bi-directional environment-economy links are quantified and incorporated. (C) 2011 Elsevier Ltd. All rights reserved.