Toyoaki Washida

Weighting across safeguard subjects for LCIA through the application of conjoint analysis

BackgroundMany types of weighting methods, which have integrated the various environmental impacts that are used for life-cycle impact assessment (LCIA), were proposed with the aim of developing the methodology as a useful information resource for decision making, such as in the selection of products. Economic valuation indexes, in particular, have attracted attention, as their assessment results are easy to understand and can be applied in conjunction with other assessment tools, including life-cycle costing (LCC) and environmental accounting. Conjoint analysis has been widely used in market research, and has recently been applied to research in environmental economics. The method enables us to provide two types of assessment results; an economic valuation and a dimensionless index. This method is therefore expected to contribute greatly to increasing the level of research into weighting methodology, in which an international consensus has yet to be established. Conjoint analysis, however, has not previously been applied to LCIA.ObjectiveLCA National Project (METI/NEDO/JEMAI) has conducted a study aimed at the development of a Japanese version of the damage-oriented impact assessment method called LIME (Life-cycle Impact assessment Method based on Endpoint modeling), in order to enhance its reliability and transparency. This study aimed at the application of conjoint analysis to the step of weighting in LIME. An ultimate goal of the research is to determine an amount of willingness to pay (WTP) for avoiding a unit quantity of damage of every safeguard subject (endpoint).MethodsPotential annual damages of four safeguard subjects (human health, biodiversity, social assets, and primary production), known as normalization values in LCIA, were used as fundamental information in this study. These data can be obtained through damage assessment. Taking this background into account, we performed a comparison of importance among the four safeguard subjects defined in LIME by applying conjoint analysis. A choice-based type of questionnaire was prepared for the interview with the respondents selected by random sampling. Pre-tests were conducted for 108 respondents in advance of the main survey. After we confirmed that the analyzed results of the pre-test were revealed to be statistically significant, the main surveys were conducted for 400 respondents by interviewing. WTP per quota can be determined by statistical simulation based on the random utility theory reflecting the responses to the questionnaires by random sampling.Results and DiscussionThe values of one unit (standard) of attributes were significant statistically at the 1% level (all of the p value for coefficients of safeguard subjects were less than 0.0001). Based on the calculated results, two types of weighting factors, an economic valuation and a dimensionless index were obtained. The capability of generating two kinds of weighting factors is unique to conjoint analysis. A relative comparison of importance among the four categories indicates that human health gains the highest recognition, biodiversity gains the second highest recognition, and the weight of primary production and social assets have been estimated to be relatively smaller than the other two safeguard subjects.ConclusionIt is desirable to prepare a small number of attributes when conducting a conjoint analysis, because the efforts of respondents have to be reduced as far as possible. We confirmed that the damage-oriented method, which minimizes the number of attributes, is suitable to the requirement of conjoint analysis, because the results of comparisons among safeguard subjects were statistically significant, and showed that the contents of the questionnaires were well understood among the respondents. Judging from the results of this study, where statistical significance has not even been fully verified in the conventional research on the development of weighting coefficients for LCIA, it can be concluded that the weighting factors derived from this study based on the economic theory have a possibility to reveal the impact of environment on society.

Economic valuation of the Seto Inland Sea by using an Internet CV survey.

We estimate the economic value of the natural environment damaged in the Seto Inland Sea after the introduction of the Law on Temporary Measures for the Environmental Conservation of the Seto Inland Sea (Setouchi Law) and the value of the natural environment that survived, using a Contingent Valuation (CV) survey on an Internet web site. The CV survey contains three plans. Plan 1 is to restore 4 ha of reclaimed land. By estimating the Willingness To Pay (WTP) for plan 1, we can appraise the value of the natural environment that was damaged as a result of the original reclamation. Plan 2 is to transplant Zostera (eel-grass) into an area of 10 ha offshore. Plan 3 is to preserve the shore area, a natural habitat for rare animal species, under the National Trust Program. From the WTP for plans 2 and 3, we can estimate the value of the shore area and the areas a little farther offshore. The value of the natural environment damaged in the Seto Inland Sea as a result of reclaiming projects after the introduction of the Setouchi Law and the value of the existing natural environment of the Seto Inland Sea from the WTP for the plans were estimated to about 172 trillion yen (1.46 trillion dollars) and about 424 trillion yen (3.60 trillion dollars), respectively. The results indicate that in the 25 years since the introduction of the Setouchi Law, we have degraded every year about 6.88 trillion yen (58.5 billion dollars) worth of the natural environment by reclaiming. Some seaweed farms and natural shore areas, natural habitats to rare marine life-forms like the horseshoe crab and the fiddler crab have survived, but their value amounts to about 80% of Japans GDP.

Computable general equilibrium analyses of global economic impacts and adaptation for climate change: the case of tropical cyclones

Computable general equilibrium models have been widely used for simulating global warming and evaluating economic damages caused by climate change. However, to date little research has focused on the economic consequences incurred across several industry sectors at a global level. This article uses the evaluation model for environmental damage and adaptation (EMEDA) to simulate direct economic damages caused by tropical cyclones and losses that are offset through growth in other sectors to measure the global economic impacts arising from climate change. Simulated results by EMEDA indicate that: 1) several regions experience economic growth, with four regions offsetting economic damages in the primary industry sector whilst the other regions increase their damages; 2) seven regions show economic growth whilst only North America neutralises damage in their secondary sectors, with the other regions revealing more severe losses; 3) several regions are able to offset their tertiary sector losses yet the other regions show an increase in damages; 4) the equivalent variation in all regions except East Asia decreases as temperature increases.

Assessment of mitigation strategies as tools for risk management under future uncertainties: a multi-model approach

Although the world understands the possible threat of the future of climate changes, there remain serious barriers to be resolved in terms of policy decisions. The scientific and the societal uncertainties in the climate change policies must be the large part of this barrier. Following the Paris Agreement, the world comes to the next stage to decide the next actions. Without a view of risk management, any decision will be “based on neglecting alternatives” behavior. The Ministry of the Environment, Japan has established an inter-disciplinary research project, called Integrated Climate Assessment—Risks, Uncertainties, and Society (ICA-RUS) conducted by Dr. Seita Emori, National Institute for Environmental Studies. ICA-RUS consists of five research themes, i.e., (1) synthesis of global climate risks, (2) optimization of land, water, and ecosystem for climate risks, (3) analysis of critical climate risks, (4) evaluation of climate risk management options, and (5) interactions between scientific and social rationalities. We participated in the fourth theme to provide the quantitative assessment of technology options and policy measures by integrating assessment model simulations. We employ the multi-model approach to deal with the complex relationships among various fields such as technology, economics, and land use changes. Four different types of integrated assessment models, i.e., MARIA-14 (Mori), EMEDA (Washida), GRAPE (Kurosawa), and AIM (Masui), participate in the fourth research theme. These models contribute to the ICA-RUS by providing two information categories. First, these models provide common simulation results based on shared socioeconomic pathway scenarios and the shared climate policy cases given by the first theme of ICA-RUS to see the ranges of the evaluation. Second, each model also provides model-specific outcomes to answer special topics, e.g., geoengineering, sectoral trade, adaptation, and decision making under uncertainties. The purpose of this paper is to describe the outline and the main outcomes of the multi-model inter-comparison among the four models with a focus upon the first and to present the main outcomes. Furthermore, in this study, we introduce a statistical meta-analysis of the multi-model simulation results to see whether the differently structured models provide the inter-consistent findings. The major findings of our activities are as follows: First, in the stringent climate target, the regional economic losses among models tend to diverge, whereas global total economic loss does not. Second, both carbon capture and storage (CCS) as well as BECCS are essential for providing the feasibility of stringent climate targets even if the deployment potential varies among models. Third, the models show small changes in the crop production in world total, whereas large differences appear between regions. Fourth, the statistical meta-analysis of the multi-model simulation results suggests that the models would have an implicit but common relationship between gross domestic product losses and mitigation options even if their structures and simulation results are different. Since this study is no more than a preliminary exercise of the statistical meta-analysis, it is expected that more sophisticated methods such as data mining or machine learning could be applicable to the simulation database to extract the implicit information behind the models.

Material dissipative conditions and the impossibility of complete recycling

Abstract The preservation of the natural envirnonment requires a reduction in material intensity of economic systems. Recycling is a major method for meeting this requirement. One of the most appropriate formulations for economic recycling models is the introduction of recycling sectors and joint production of waste materials. The models are generally checked for the feasibility of net-production. Such models may be able to realize complete recycling material resources, but this is clearly impossible due to the unrecoverable material dissipation in economic production processes. The result is that the models have sometimes reproduced material resources larger than the initial input of virgin material. This paper introduces the material dissipative conditions and the material transferability system appropriate for recognizing the material dissipation of economic systems with recycling sectors.