Area of concern: a new paradigm in life cycle assessment for the development of footprint metrics
As a class of environmental metrics, footprints have been poorly defined, have shared an unclear relationship to life cycle assessment (LCA), and the variety of approaches to quantification have sometimes resulted in confusing and contradictory messages in the marketplace. In response, a task force operating under the auspices of the UNEP/SETAC Life Cycle Initiative project on environmental life cycle impact assessment (LCIA) has been working to develop generic guidance for developers of footprint metrics. The purpose of this paper is to introduce a universal footprint definition and related terminology as well as to discuss modelling implications.
The task force has worked from the perspective that footprints should be based on LCA methodology, underpinned by the same data systems and models as used in LCA. However, there are important differences in purpose and orientation relative to LCA impact category indicators. Footprints have a primary orientation toward society and nontechnical stakeholders. They are also typically of narrow scope, having the purpose of reporting only in relation to specific topics. In comparison, LCA has a primary orientation toward stakeholders interested in comprehensive evaluation of overall environmental performance and trade-offs among impact categories. These differences create tension between footprints, the existing LCIA framework based on the area of protection paradigm and the core LCA standards ISO14040/44.
Results and discussion
In parallel to area of protection, we introduce area of concern as the basis for a universal footprint definition. In the same way that LCA uses impact category indicators to assess impacts that follow a common cause-effect pathway toward areas of protection, footprint metrics address areas of concern. The critical difference is that areas of concern are defined by the interests of stakeholders in society rather than the LCA community. In addition, areas of concern are stand-alone and not necessarily part of a framework intended for comprehensive environmental performance assessment. The area of concern paradigm is needed to support the development of footprints in a way that fulfils their distinctly different purpose. It is also needed as a mechanism to extricate footprints from some of the provisions of ISO 14040/44 which are not considered relevant. Specific issues are identified in relation to double counting, aggregation and the selection of relevant indicators.
The universal footprint definition and related terminology introduced in this paper create a foundation that will support the development of footprint metrics in parallel with LCA.
KeywordsArea of protection Environmental footprint Environmental labels and declarations Footprint definition Footprint indicator ISO 14044 Life cycle impact assessment UNEP/SETAC Life Cycle Initiative
Acknowledgments and disclaimer
This work is supported by the United Nations Environment Programme (UNEP)/Society of Environmental Toxicology and Chemistry (SETAC) Life Cycle Initiative. Public and private sector sponsors are listed on the Initiative’s website (http://www.lifecycleinitiative.org/). The views expressed in this article are those of the authors and do not necessarily reflect those of the various affiliated organisations.
- EC JRC [European Commission, Joint Research Centre] (2010) International Reference Life Cycle Data System (ILCD) handbook—general guide for life cycle assessment—detailed guidance. Publications Office of the European Union, LuxembourgGoogle Scholar
- ISO 14025 (2006) Environmental labels and declarations—type III environmental declarations—principles and procedures. International Organization for Standardization, GenevaGoogle Scholar
- ISO 14040 (2006) Environmental management—life cycle assessment—principles and framework. International Organization for Standardization, GenevaGoogle Scholar
- ISO 14044 (2006) Environmental management—life cycle assessment—requirements and guidelines. International Organization for Standardization, GenevaGoogle Scholar
- ISO 14046 (2014) Environmental management—water footprint—principles, requirements and guidelines. International Organization for Standardization, GenevaGoogle Scholar
- ISO/TS 14067 (2013) Greenhouse gases—carbon footprint of products—requirements and guidelines for quantification and communication. International Organization for Standardization, GenevaGoogle Scholar
- ISO/TS 14072 (2014) Environmental management—life cycle assessment—requirements and guidelines for organizational life cycle assessment. International Organization for Standardization, GenevaGoogle Scholar
- Jolliet O, Frischknecht R, Bare J, Boulay AM, Bulle C, Fantke P, Gheewala S, Hauschild M, Itsubo N, Margni M, McKone TE, Mila y Canals L, Posthuma L, Prado-Lopez V, Ridoutt B, Sonnemann G, Rosenbaum RK, Seager T, Struijs J, van Zelm R, Vigon B, Weisbrod A (2014) Global guidance on environmental life cycle impact assessment indicators: findings of the scoping phase. Int J Life Cycle Assess 19(4):962–967CrossRefGoogle Scholar
- Ridoutt B, Fantke P, Pfister S, Bare J, Boulay AM, Cherubini F, Frischknecht R, Hauschild M, Hellweg S, Henderson A, Jolliet O, Levasseur A, Margni M, McKone T, Michelsen O, Milà i Canals L, Page G, Pant R, Raugei M, Sala S, Saouter E, Verones F, Wiedmann T (2015) Making sense of the minefield of footprint indicators. Environ Sci Technol 49(5):2601–2603CrossRefGoogle Scholar
- UNEP (2015) Guidance on organizational life cycle assessment. UNEP/SETAC Life Cycle Initiative, TU Berlin and Kogakuin University, ParisGoogle Scholar