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nologies and the transformation of in-use stocks that leads to new recycling
opportunities, resource depletion, and declining ore grades.
(2) Assessment at full scale: The ultimate goal of the coming transformation is
to rescale human activity to a level that can be sustained by nature in the
long run and that allows for future human development at the same time.
Identifying the appropriate scale of human activity requires us to study
socioeconomic metabolism on the global level, which was not necessary to
understand the previous socioeconomic transitions.
Socioeconomic metabolism is a nonlinear system, which means that the
impact of upscaling small modifi cations to the system is in general not proportional to the scaling factor. The upscaling of certain sustainable development strategies is subject to local and global constraints for, e.g., land, water,
or mineral resources. Moreover, large-scale implementation of certain strategies feeds back into the system and causes structural change. Examples
include changing recycling systems, technology learning, or rebound and
spillover effects (Hertwich 2005 ). The total system-wide impact of the strategies’ potential effect can therefore only be reliably assessed if the latter are
studied at full scale, so that constraints and feedbacks can be included in the
assessment.
(3a–c) Multilayer modeling , satellite accounts , and balancing constraints allow
scientists from different disciplines, like industrial ecologists and economists, to use a consistent framework to describe society’s metabolism and to
address a variety of research questions. In multilayer modeling, the physical
and economic properties of objects are quantifi ed in consistent parallel
frameworks (Pauliuk et al. 2015 ; Schmidt et al. 2012 ). Satellite accounts,
like emissions to nature or labor requirements, contain additional information about how society’s metabolism is connected to the environment and to
human agents. They form the interface between models of SEM and those
from other scientifi c disciplines, like climate models or environmental
impact assessment. Balancing constraints for the physical and monetary layers, like industry or market balances, is the most fundamental way to check
the validity of a prospective system description. Prospective models should
always respect these fundamental balances.
(4) Scenario modeling with exogenous parameters acknowledges the indeterminacy of future development and reduces system complexity to a manageable
level. Only with scenario modeling one can build scientifi cally credible prospective models of complex indeterminate systems like socioeconomic
metabolism. This central aspect of prospective modeling needs some more
elaboration.
Socioeconomic metabolism is a non-isolated and non-deterministic complex system. It is not isolated, because it exchanges energy and matter with
the inner of the Earth and with space. SEM is non-deterministic, because it
is controlled by human agents that use their environmental literacy to intervene and divert the system from its current trajectory in a non-predictable
2 Prospective Models of Society’s Future Metabolism: What Industrial Ecology Has…
nologies and the transformation of in-use stocks that leads to new recycling
opportunities, resource depletion, and declining ore grades.
(2) Assessment at full scale: The ultimate goal of the coming transformation is
to rescale human activity to a level that can be sustained by nature in the
long run and that allows for future human development at the same time.
Identifying the appropriate scale of human activity requires us to study
socioeconomic metabolism on the global level, which was not necessary to
understand the previous socioeconomic transitions.
Socioeconomic metabolism is a nonlinear system, which means that the
impact of upscaling small modifi cations to the system is in general not proportional to the scaling factor. The upscaling of certain sustainable development strategies is subject to local and global constraints for, e.g., land, water,
or mineral resources. Moreover, large-scale implementation of certain strategies feeds back into the system and causes structural change. Examples
include changing recycling systems, technology learning, or rebound and
spillover effects (Hertwich 2005 ). The total system-wide impact of the strategies’ potential effect can therefore only be reliably assessed if the latter are
studied at full scale, so that constraints and feedbacks can be included in the
assessment.
(3a–c) Multilayer modeling , satellite accounts , and balancing constraints allow
scientists from different disciplines, like industrial ecologists and economists, to use a consistent framework to describe society’s metabolism and to
address a variety of research questions. In multilayer modeling, the physical
and economic properties of objects are quantifi ed in consistent parallel
frameworks (Pauliuk et al. 2015 ; Schmidt et al. 2012 ). Satellite accounts,
like emissions to nature or labor requirements, contain additional information about how society’s metabolism is connected to the environment and to
human agents. They form the interface between models of SEM and those
from other scientifi c disciplines, like climate models or environmental
impact assessment. Balancing constraints for the physical and monetary layers, like industry or market balances, is the most fundamental way to check
the validity of a prospective system description. Prospective models should
always respect these fundamental balances.
(4) Scenario modeling with exogenous parameters acknowledges the indeterminacy of future development and reduces system complexity to a manageable
level. Only with scenario modeling one can build scientifi cally credible prospective models of complex indeterminate systems like socioeconomic
metabolism. This central aspect of prospective modeling needs some more
elaboration.
Socioeconomic metabolism is a non-isolated and non-deterministic complex system. It is not isolated, because it exchanges energy and matter with
the inner of the Earth and with space. SEM is non-deterministic, because it
is controlled by human agents that use their environmental literacy to intervene and divert the system from its current trajectory in a non-predictable
2 Prospective Models of Society’s Future Metabolism: What Industrial Ecology Has…