Per Wikman-Svahn

Tailor-made scenario planning for local adaptation to climate change

This paper presents a tailor-made scenario approach for climate change adaptation planning, which emphasises involvement of stakeholders in the development of socioeconomic scenarios and relates to the planning situation and interest of the planning entity. The method was developed and tested in case studies in three different sectors in Sweden (the health sector, the tourism sector and water resource management). The result of the case studies is that the tailor-made scenario approach facilitated the engagement of the local planning body in climate change adaptation and helped them to analyse consequences and possible solutions in a structured way. However, the scenarios that emerged mainly focused on socioeconomic drivers on which the planning body had a large impact or drivers that can be influenced through cooperation with other actors at the local or regional level. While this result underlines the need for local stakeholder involvement in scenario processes, it also indicates a local bias that could be remedied by a stronger representation of national and global perspectives in the scenario development process. Finally, we discuss how a “bottom-up” approach could be combined with a “consistency” approach, which points towards a possible way forward to a hybrid methodology that is compatible with the scenario framework currently being developed in connection to the fifth assessment report of the IPCC.

Characterizing Uncertain Sea Level Rise Projections to Support Investment Decisions

Many institutions worldwide are considering how to include uncertainty about future changes in sea-levels and storm surges into their investment decisions regarding large capital infrastructures. Here we examine how to characterize deeply uncertain climate change projections to support such decisions using Robust Decision Making analysis. We address questions regarding how to confront the potential for future changes in low probability but large impact flooding events due to changes in sea-levels and storm surges. Such extreme events can affect investments in infrastructure but have proved difficult to consider in such decisions because of the deep uncertainty surrounding them. This study utilizes Robust Decision Making methods to address two questions applied to investment decisions at the Port of Los Angeles: (1) Under what future conditions would a Port of Los Angeles decision to harden its facilities against extreme flood scenarios at the next upgrade pass a cost-benefit test, and (2) Do sea-level rise projections and other information suggest such conditions are sufficiently likely to justify such an investment? We also compare and contrast the Robust Decision Making methods with a full probabilistic analysis. These two analysis frameworks result in similar investment recommendations for different idealized future sea-level projections, but provide different information to decision makers and envision different types of engagement with stakeholders. In particular, the full probabilistic analysis begins by aggregating the best scientific information into a single set of joint probability distributions, while the Robust Decision Making analysis identifies scenarios where a decision to invest in near-term response to extreme sea-level rise passes a cost-benefit test, and then assembles scientific information of differing levels of confidence to help decision makers judge whether or not these scenarios are sufficiently likely to justify making such investments. Results highlight the highly-localized and context dependent nature of applying Robust Decision Making methods to inform investment decisions.

Planning for future sea-level rise in Swedish municipalities

A warmer climate leads to rising sea levels. Despite uncertainties about how rapid and substantial future sea-level rise (SLR) will be, society needs to prepare and adapt. This study examines the state of planning for future SLR in Sweden by surveying 33 coastal municipalities in southern Sweden and interviewing local, regional and national authorities with relevant accountability. The results reveal that there are considerable gaps in current planning for SLR. Almost one-third of municipalities lack guiding planning documents for SLR, and more than two-thirds do not discuss SLR beyond 2100. We argue that the prevailing uncertainty and ambiguity in assessments of future SLR is problematic within a traditional “predict-then-act” paradigm, and that robust approaches, such as scenario planning, can reduce many of these problems.

Principles of protection: a formal approach for evaluating dose distributions.

One of the central issues in radiation protection consists in determining what weight should be given to individual doses in relation to collective or aggregated doses. A mathematical framework is introduced in which such assessments can be made precisely in terms of comparisons between alternative distributions of individual doses. In addition to evaluation principles that are well known from radiation protection, a series of principles that are derived from parallel discussions in moral philosophy and welfare economics is investigated. A battery of formal properties is then used to investigate the evaluative principles. The results indicate that one of the new principles, bilinear prioritarianism, may be preferable to current practices, since it satisfies efficiency-related properties better without sacrificing other desirable properties.

Choosing small sets of policy-relevant scenarios by combining vulnerability and diversity approaches

Computer simulation models can generate large numbers of scenarios, far more than can be effectively utilized in most decision support applications. How can one best select a small number of scenarios to consider? One approach calls for choosing scenarios that illuminate vulnerabilities of proposed policies. Another calls for choosing scenarios that span a diverse range of futures. This paper joins these two approaches for the first time, proposing an optimization-based method for choosing a small number of relevant scenarios that combine both vulnerability and diversity. The paper applies the method to a real case involving climate resilient infrastructure for three African river basins (Volta, Orange and Zambezi). Introducing selection criteria in a stepwise manner helps examine how different criteria influence the choice of scenarios. The results suggest that combining vulnerability- and diversity-based criteria can provide a systematic and transparent method for scenario selection. Describes an optimization-based method for choosing a small number of scenarios.A combination of criteria related to vulnerability and diversity is used.The method is applied to a real case involving climate resilient infrastructure.

Black Elephants and Black Swans of Nuclear Safety

This thesis is based on the assumption that the intersection of moral philosophy and practical risk management is a rewarding area to study. In particular, the thesis assumes that concepts, ideas, and methods that are used in moral philosophy can be of great benefit for risk analysis, but also that practices in risk regulation provide a useful testing ground for moral philosophical theories. The thesis consists of an introduction and five articles.Article I is a review article on social and ethical aspects of radiation protection related to nuclear power generation. The paper concludes that four areas of social and ethical issues stand out as central: The first is uncertainty and the influence of value judgments in scientific risk assessments. The second is the distributions of risks and benefits between different individuals, in both space and time. The third is the problem of setting limits when there is no known level of exposure associated with a zero risk. The fourth is related to stakeholder influence and risk communication.Article II discusses ethical issues related to the proposal that doses (or risks) below a certain level should be excluded from the system of radiation protection, without any regard for the number of people exposed. Different arguments for excluding small radiation doses from regulation are examined and a possible solution to the problem of regulating small risks is proposed in the article: Any exclusion of small doses (or risks) from radiation protection ought to be based on a case-by-case basis, with the condition that the expected value of harm remains small.Article III examines what makes one distribution of individual doses better than another distribution. The article introduces a mathematical framework based on preference logic, in which such assessments can be made precisely in terms of comparisons between alternative distributions of individual doses. Principles of radiation protection and from parallel discussions in moral philosophy and welfare economics are defined using this framework and their formal properties analyzed.Article IV argues that the ethical theory of “responsibility-catering prioritarianism” is well positioned to deal with the reasonable requirements in an ethical theory of risk. The article shows how responsibility-catering prioritarianism can be operationalized using a prioritarian social welfare function based on hypothetical utilities. For this purpose, a hypothetical utility measure called ‘responsibility-adjusted utility’ is proposed, which is based on the utility that would normally be expected given circumstances outside of the control of the individual.Article V was written as a response to the Fukushima disaster. Several authors have called the Fukushima disaster a ‘black swan.’ However, the article argues that the hazards of large earthquakes and tsunamis were known before the accident, and introduces and defines the concept of a ‘black elephant,’ as (i) a high-impact event that (ii) lies beyond the realm of regular expectations, but (iii) is ignored despite existing evidence.

Toward a Responsibility-catering Prioritarian Ethical Theory of Risk

Standard tools used in societal risk management such as probabilistic risk analysis or cost–benefit analysis typically define risks in terms of only probabilities and consequences and assume a utilitarian approach to ethics that aims to maximize expected utility. The philosopher Carl F. Cranor has argued against this view by devising a list of plausible aspects of the acceptability of risks that points towards a non-consequentialist ethical theory of societal risk management. This paper revisits Cranor’s list to argue that the alternative ethical theory responsibility-catering prioritarianism can accommodate the aspects identified by Cranor and that the elements in the list can be used to inform the details of how to view risks within this theory. An approach towards operationalizing the theory is proposed based on a prioritarian social welfare function that operates on responsibility-adjusted utilities. A responsibility-catering prioritarian ethical approach towards managing risks is a promising alternative to standard tools such as cost–benefit analysis.