The risk posed by anthropogenic climate change is generally accepted, and the challenge we face to reduce greenhouse gas (GHG) emissions to a tolerable limit cannot be underestimated. Reducing GHG emissions can be achieved either by producing less GHG to begin with or by emitting less GHG into the atmosphere. One carbon mitigation technology with large potential for capturing carbon dioxide at the point source of emissions is carbon capture and storage (CCS). However, the merits of CCS have been questioned, (...) both on practical and ethical grounds. While the practical concerns have already received substantial attention, the ethical concerns still demand further consideration. This article aims to respond to this deficit by reviewing the critical ethical challenges raised by CCS as a possible tool in a climate mitigation strategy and argues that the urgency stemming from climate change underpins many of the concerns raised by CCS. (shrink)

Several areas of welfare economics seek to evaluate states of affairs as a function of interpersonally comparable individual utilities. The aim is to map each state of affairs onto a vector of individual utilities, and then to produce an ordering of these vectors that can be represented by a mathematical function assigning a real number to each. When this approach is used in intertemporal contexts, a central theoretical question concerns the evaluative weight to be applied to utility coming at different (...) times. This question concerns the rate of pure time preference, which is one key determinant of the social discount rate. This article argues that the standard philosophical account of pure time preference is mistaken, because it ascribes to economists a methodological commitment they need not, and often do not, accept. This in turn undercuts the most common philosophical objection to pure time preference, which traces at least to Rawls’s A Theory of Justice. The article then evaluates three further objections to pure time preference, concluding that it might still be defensible under certain circumstances. The article closes by articulating a final argument that is suggested by the “Social, Economic and Ethical Concepts and Methods” chapter of the most recent Intergovernmental Panel on Climate Change report. If this further argument is sound, it would constitute a decisive objection to pure time preference as it currently figures in much intertemporal welfare economics. (shrink)

Controversies about time discounting loom large in decisions about climate change. Prominently, a particularly controversial debate about time discounting in climate change decision-making has been conducted within climate economics, between the authors of Stern et al. and their critics :977–981, 2006; Weitzman in J Econ Lit XLV:703–724, 2007; Nordhaus in J Econ Lit XLV:686–702, 2007). The article examines the role of values in this debate. Firstly, it is shown that time discounting is a case in which values are key because (...) it is at heart an ethical problem. Secondly, it is argued that time discounting in climate economics is a case of economists making frequent and routine references to ethical values and indeed conduct ethical debates with each other. Thirdly, it is argued that there is evidence for deep and pervasive entanglement between facts and values in the prevalent methodologies for time discounting. Finally, it is argued that this means that economists have given up the ‘value-free ideal’ concerning time discounting, and discussed how the current methodology of time discounting in economics can be improved. (shrink)

It is often claimed that reducing population size would be advantageous for climate change mitigation, on the grounds that lower population would naturally correspond to lower emissions. This apparently obvious claim is in fact seriously misleading. Reducing population size would indeed, other suitable things being equal, reduce the emissions rate. But it is well recognised that the primary determinant of the eventual amount of climate change is not the emissions rate, but rather cumulative emissions. It is far less clear whether (...) reducing population size would reduce cumulative emissions, or would in any other way prove an advantage for reasons related to climate change. This paper identifies and briefly discusses the issues relevant to assessing that less clear question. (shrink)

Is drastic action against global warming essential to avoid impoverishing our descendants? Or does it mean robbing the poor to give to the rich? We do not yet know. Yet most of us can agree on the importance of minimising expected deprivation. Because of the vast number of future generations, if there is any significant risk of catastrophe, this implies drastic and expensive carbon abatement unless we discount the future. I argue that we should not discount. Instead, the rich countries (...) should stump up the funds to support abatement both for themselves and the poor states of the world. Yet to ask the present generation to assume all the costs of drastic mitigation.is unfair.Worse still, it is politically unrealistic.We can square the circle by shifting part of the burden to our descendants. Even if we divert investment from other parts of the economy or increase public debt, future people should be richer, so long as we avert catastrophe. If so, it is fair for them to assume much of the cost of abatement.What we must not do is to expose them to the threat of disaster by not doing enough. (shrink)

Overpopulation is often identified as one of the key drivers of climate change. Further, it is often thought that the mechanism behind this is obvious: 'more people means more greenhouse gas emissions'. However, in light of the fact that climate change depends most closely on cumulative emissions rather than on emissions rates, the relationship between population size and climate change is more subtle than this. Reducing the size of instantaneous populations can fruitfully be thought of as spreading out a fixed (...) number of people more thinly over time, and (in light of the significance of cumulative emissions) it is not immediately clear whether or how such a 'spreading' would help with climate change. To bring the point into sharp relief, I first set out a simple model according to which population reduction would not lead to any climate-change-related improvement. I then critically examine the assumptions of the model. If population reduction would lead to a significant climate-change-related improvement, this must be because (i) population reduction would significantly reduce even cumulative emissions, and/or (ii) climate damages are, to a significant extent, driven by the pace of climate change, and not only the eventual extent of the change. (shrink)

I discuss three families of methodologies that could be used to assign values to the normative parameters relevant to social discounting in welfare economics generally, and climate economics more specifically. First, I argue that in particular circumstances, there cannot be philosophical argumentation for normative questions; specifically, this occurs when the particular values being sought are both non-critical and from a quantitative range. Second, I argue that social preferences are insufficient if we take the problem to be normative and that proposals (...) for informed social preferences face significant challenges in implementation. Finally, I argue in favour of expert elicitation for experts in welfare economics, construed as those who understand the theoretical implications of adopting particular judgments. Those who understand the theoretical implications of adopting particular judgments will be better placed to develop coherent social plans while integrating relevant empirical data. (shrink)