3.4 Discussion
53
and this is probably the initial purpose of footprint analysis. Although sometimes
there are some simple conversions in the inventory phase of IVOP calculations,
valuable physical information is maintained in relation to pressure exerted by the
emission of wastes and extraction of resources. These merits, however, are obtained
at the expense of undermining environmental relevance because assigned weighting
factors are subject to artificial sequences that are almost unwarranted.
According to ISO (2006), footprint weighting is suggested as an option for further
evaluation in the context of product LCA. One may easily extend this message to
organizations and nations, in order to meet the non-professional demands (e.g., policy
making, public communication) for a single-score, stand-alone metric for purposes of
easy interpretation and trade-off analysis. In an attempt to standardize the integration
of environmental footprints, our study has ascertained that integrating either the
IVOFs or a mixture of the IVOFs and IPOFs is technically feasible but essentially
meaningless. That is to say, it makes sense only if a set of carefully selected IPOFs
are under consideration. Resembling the general procedure for LCIA, a three-step
framework has been proposed for characterization, normalization, and weighting of
the IPOFs. Admittedly this is not much new for LCA experts, but we believe that it
provides non-LCA experts with new insights into the fundamental nature of footprints
and, more importantly, that it can serve as a unifying framework for discussions in
communities that are quite disparate at the present moment, such as those of LCA,
the water footprint, and the ecological footprint.
3.5 Conclusions
We herein come up with some conclusions that are supposed to fuel the ongoing
discourse on a truly integrated footprint family. First, value-based weighting is hardly
avoidable when integrating different footprint indicators into a single composite
metric, because a thorough characterization model able to capture the full characteristics of related environmental impacts is virtually non-existent. Second, double
counting and double weighting can nevertheless be avoided by the substitution of
characterization factors for inventory weighting prior to footprint weighting. Third,
the two categories of footprints identified offer two competing paradigms for the
development of footprint indicators. Last, the ICNW logic could contribute to the
standardization of footprint accounting—a more general framework that is inspired
by the results of two decades of intense debate in the LCA community, but that can
also be fruitful in life cycle-less contexts where there is no clear life cycle or even
without an LCA. As a whole, the main value added of this chapter is the establishment of a unified framework for structuring, categorizing, and integrating different
footprints.
Accordingly, it should be emphasized that our proposal for restricting the integration practices to the IPOFs does not challenge the validity of the IVOFs, as the latter
is appropriate for use in identifying the driving forces of environmental issues using
53
and this is probably the initial purpose of footprint analysis. Although sometimes
there are some simple conversions in the inventory phase of IVOP calculations,
valuable physical information is maintained in relation to pressure exerted by the
emission of wastes and extraction of resources. These merits, however, are obtained
at the expense of undermining environmental relevance because assigned weighting
factors are subject to artificial sequences that are almost unwarranted.
According to ISO (2006), footprint weighting is suggested as an option for further
evaluation in the context of product LCA. One may easily extend this message to
organizations and nations, in order to meet the non-professional demands (e.g., policy
making, public communication) for a single-score, stand-alone metric for purposes of
easy interpretation and trade-off analysis. In an attempt to standardize the integration
of environmental footprints, our study has ascertained that integrating either the
IVOFs or a mixture of the IVOFs and IPOFs is technically feasible but essentially
meaningless. That is to say, it makes sense only if a set of carefully selected IPOFs
are under consideration. Resembling the general procedure for LCIA, a three-step
framework has been proposed for characterization, normalization, and weighting of
the IPOFs. Admittedly this is not much new for LCA experts, but we believe that it
provides non-LCA experts with new insights into the fundamental nature of footprints
and, more importantly, that it can serve as a unifying framework for discussions in
communities that are quite disparate at the present moment, such as those of LCA,
the water footprint, and the ecological footprint.
3.5 Conclusions
We herein come up with some conclusions that are supposed to fuel the ongoing
discourse on a truly integrated footprint family. First, value-based weighting is hardly
avoidable when integrating different footprint indicators into a single composite
metric, because a thorough characterization model able to capture the full characteristics of related environmental impacts is virtually non-existent. Second, double
counting and double weighting can nevertheless be avoided by the substitution of
characterization factors for inventory weighting prior to footprint weighting. Third,
the two categories of footprints identified offer two competing paradigms for the
development of footprint indicators. Last, the ICNW logic could contribute to the
standardization of footprint accounting—a more general framework that is inspired
by the results of two decades of intense debate in the LCA community, but that can
also be fruitful in life cycle-less contexts where there is no clear life cycle or even
without an LCA. As a whole, the main value added of this chapter is the establishment of a unified framework for structuring, categorizing, and integrating different
footprints.
Accordingly, it should be emphasized that our proposal for restricting the integration practices to the IPOFs does not challenge the validity of the IVOFs, as the latter
is appropriate for use in identifying the driving forces of environmental issues using