An Empirical Environmental Sustainability Index Derived Solely from Nighttime Satellite Imagery and Ecosystem Service Valuation.” Population and Environment

This paper describes a crude yet simple Environmental Sustainability Index (ESI) derived solely from the ratio of two classified satellite images with global coverage. An ESI is calculated for each nation of the world by dividing the amount of light energy emitted by that nation as measured by a nighttime satellite image into the total value of that nation’s ecosystem services as measured by a land-cover dataset and ecosystem service values estimated by Costanza et. al. (Costanza, d’Arge et al., 1997). The strength of this ESI is its simplicity and global coverage (other ESIs in-volve hundreds of variables which usually entail many ‘data gaps’). The utility of this ESI is not as ‘the ’ measure of environmental sustainability but as ‘a ’ measure that can be compared to other ESIs in interesting and informative ways. Measuring environmental sustainability is a difficult challenge that is being undertaken by more and more people and institutions using a wide variety of methods. If indepen-dent measures of sustainability do not correspond reasonably well with one another then the practical utility of deriving ESIs will be undermined because the exercise will be perceived as more political than scientific. Two sophisticated ESIs are exam-ined and compared to this simple one: 1) The 2001 Environmental Sustainability Index derived as an initiative of the Global Leaders of Tomorrow Environment Tas