Is there more in common than we think? Convergence of ecological footprinting, emergy analysis, life cycle assessment and other methods of environmental accounting

- Biophysical environmental accounting methods are critically reviewed.
- Methods all analyse networks and indirect environmental effects within networks.
- Methods all have similar underlying mathematical structures − the math of networks.
- Methods all identify same methodological problems, but disagree on how to solve them.
- Methods need to co-learn from each other and not be so idiosyncratic.

Over the last four decades, Environmental Accounting tools have been developed to conceptualise and quantify the direct and indirect effects of human activity on the environment, to enable decision-makers to track and measure progress towards sustainability outcomes and goals. These environmental accounting methods range from ecological footprinting, carbon footprinting, energy analysis, emergy analysis, ecological pricing and life cycle assessment to environmental input-output analysis. Regrettably, the contemporaneous development of these tools has frequently occurred in isolation from each other, even though they often seek to serve common analytical and evaluative purposes, as well as serving similar communities of interest. It is the central argument of this paper that, in spite of this isolation, the environmental accounting methods have a number of common features − that is, they can be mathematically reduced to similar analytics, and they often confront the same methodological issues − e.g., joint production (co-products) problem, weighting, commensuration, double counting and boundary setting. In this regard the paper reviews how the various environmental accounting tools can 'learn' from each other − e.g., how the mathematics of ecological pricing can address the joint production problem in a number of the other environmental accounting methods; and how the insights from input-output analysis can be used in system boundary setting. The paper concludes by agreeing with previous authors, that a better understanding of any given environmental issue is likely to be achieved by using a mix of these environmental accounting tools, rather than relying on just one tool, one perspective or one criterion.