Measures of Environmental Performance and Ecosystem Condition (1999) / Chapter Skim
Currently Skimming:
Life-Cycle Analysis: The Role of Evaluation and Strategy
Life-Cycle Analysis: The Role of Evaluation and Strategy
Pages 29-41
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 29... ...
Potential users of this technique span a wide spectrum of interests. Process and product developers view LCA as a way to incorporate environmental considerations into their design process, making it possible to anticipate and avoid potential pitfalls.
|
From page 30... ...
In such networks, the size of a particular change does not necessarily indicate the scope of its effect, and care must be taken to avoid changes that maximize local benefits at the expense of global effects. LCA is a three-step process: • inventory analysis, or the identification and quantification of energy and resource use and environmental releases to air, water, and land; • impact analysis, or the technical qualitative and quantitative characterization and assessment of the consequences of resource use and environmental releases for the environment; and • improvement analysis, or the evaluation and implementation of opportunities to reduce environmental burdens (Vigon et al., 1993)
|
From page 31... ...
Expressed simply, LCA is a tool for enhancing positive environmental impacts. Unfortunately, except in the simplest of situations, it is extremely difficult to determine how this general objective informs specific problems -- a fact that increasing numbers of LCA practitioners recognize.
|
From page 32... ...
Decision analysis refers to the points 1, 4, 5, 6, and 7 as the set of nondominated alternatives. No member of the set is better than the others in all respects.
|
From page 33... ...
Alternatively, the nonlinear preference function methods directly represent the consumer economist's classical notion of cardinal utility, where the curved line represents a line of constant utility. The curved line in Figure 3 then represents all combinations of environmental damage from A and B that leave the observer equally well (or poorly)
|
From page 34... ...
FIELD III AND JOHN R EHRENFELD 10 1 8 L 2 L Impact B 6 7 3 L L 4 L6 5 2 L 4 L 0 1 2 3 4 5 6 7 8 9 10 Impact A 10 1 8 L 2 L Impact B 6 7 3 L L 4 L6 5 2 L 4 L 0 1 2 3 4 5 6 7 8 9 10 Impact A FIGURE 3 Hypothetical set as in Figure 2 with maximum-limit lines removed and lines added that represent alternative linear and nonlinear value functions.
|
From page 35... ...
The analyst therefore cannot resolve the problem without the application of some value function, which itself must represent the strategic interests of the community that the analyst is attempting to serve. In these cases, establishing the relevant value functions will be a crucial element of the improvement analysis.
|
From page 36... ...
Two criteria are applied when establishing which impacts will become unit effects: How important the impact is on the sustainability of the environment; and is it possible to establish a quantitative value for that impact within traditional economic grounds. Examples of unit effects for human health include mortality due to increased frequency of cancer, mortality due to increased maximum temperatures, and decreases in food production (and hence increased incidence of starvation)
|
From page 37... ...
Indeed, it is debatable whether it is possible to characterize fully the unit effects of every process or activity that might be developed. However, the crucial valuation questions arise from two other aspects of this scheme: the nature of the economic measures used in calculating the cost of avoiding a unit effect and the assumption that the value of the total environmental impact of an action (the environmental load)
|
From page 38... ...
gThe F5 values represent the incremental effect of 1 kg of CO released. Because global human caused releases of CO are estimated at 1,600 million metric tons/yr, the incremental impact of 1 kg released is 6.25 × 10–13.
|
From page 39... ...
In practice, preferences usually reflect nonlinearities both in individual effects and in substitution between effects. A THIRD LIMITATION: INDIVIDUALS VERSUS GROUPS Viewing money as a measure of value and calculating linear additive preferences are not necessarily unworkable approaches when considering the development of value functions for the environment.
|
From page 40... ...
This lack of a consistent set of priorities in the environmental area essentially eliminates the possibility of constructing a useful value function. Although the EPS system is a commendable attempt at simplifying the enormous detail of inventory data, the system's developers have pointed out that it is based on their subjective value judgments, which are not necessarily supportable in all situations worldwide.
|
From page 41... ...
1982. Multiobjective Decision Analysis with Engineering and Business Applications.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.