Chapter 3
Exploring Some Fundamentals
of Environmental Footprints
Abstract Inventory and characterization schemes play different roles in shaping
a variety of footprint indicators. This chapter performs a systematic and critical
investigation into the hidden inventory aspect and characterization aspect of selected
environmental footprints with implications for classification and integration of those
footprints. It shows that all of the carbon, water, land, and material footprints
have two fundamentally distinct versions, addressing the environmental exchange
of substances in terms of emissions and/or extractions either at the inventory level
or at the impact assessment level. We, therefore, differentiate two broad categories
of environmental footprints, namely, the inventory-oriented footprints (IVOFs) and
impact-oriented footprints (IPOFs). The former allows for a physical interpretation of human pressure by inventorying emissions and extractions and aggregating
them with value-based weighting factors, whereas the latter assess and aggregate the
inventory results according to their potential contributions to a specific environmental
impact using science-based characterization factors, with the recognition that these
contributing substances are too different to be compared by mass, volume or area.
While both categories have individual strengths and weaknesses, the IPOFs have a
better performance than the IVOFs on the integration of footprints into a single-score
metric in support of policy making. Resembling the general procedure for life cycle
impact assessment (LCIA), we formulate a three-step framework for characterization, normalization, and weighting of a set of IPOFs to yield a composite footprint
index, which would allow policy makers to better assess the overall environmental
impacts of entities at multiple scales ranging from single products, organizations,
nations, even to the whole economy.
Keywords Inventory analysis · Characterization · Weighting · Life cycle impact
assessment (LCIA) · Inventory-oriented footprints (IVOFs) · Impact-oriented
footprints (IPOFs)
© The Author(s), under exclusive licence to Springer Nature Switzerland AG 2021
K. Fang, Environmental Footprints,
SpringerBriefs in Environmental Science,
https://doi.org/10.1007/978-3-030-61018-0_3
37
Exploring Some Fundamentals
of Environmental Footprints
Abstract Inventory and characterization schemes play different roles in shaping
a variety of footprint indicators. This chapter performs a systematic and critical
investigation into the hidden inventory aspect and characterization aspect of selected
environmental footprints with implications for classification and integration of those
footprints. It shows that all of the carbon, water, land, and material footprints
have two fundamentally distinct versions, addressing the environmental exchange
of substances in terms of emissions and/or extractions either at the inventory level
or at the impact assessment level. We, therefore, differentiate two broad categories
of environmental footprints, namely, the inventory-oriented footprints (IVOFs) and
impact-oriented footprints (IPOFs). The former allows for a physical interpretation of human pressure by inventorying emissions and extractions and aggregating
them with value-based weighting factors, whereas the latter assess and aggregate the
inventory results according to their potential contributions to a specific environmental
impact using science-based characterization factors, with the recognition that these
contributing substances are too different to be compared by mass, volume or area.
While both categories have individual strengths and weaknesses, the IPOFs have a
better performance than the IVOFs on the integration of footprints into a single-score
metric in support of policy making. Resembling the general procedure for life cycle
impact assessment (LCIA), we formulate a three-step framework for characterization, normalization, and weighting of a set of IPOFs to yield a composite footprint
index, which would allow policy makers to better assess the overall environmental
impacts of entities at multiple scales ranging from single products, organizations,
nations, even to the whole economy.
Keywords Inventory analysis · Characterization · Weighting · Life cycle impact
assessment (LCIA) · Inventory-oriented footprints (IVOFs) · Impact-oriented
footprints (IPOFs)
© The Author(s), under exclusive licence to Springer Nature Switzerland AG 2021
K. Fang, Environmental Footprints,
SpringerBriefs in Environmental Science,
https://doi.org/10.1007/978-3-030-61018-0_3
37