Inequality, communication, and the avoidance of disastrous climate change in a public goods game.

International efforts to provide global public goods often face the challenges of coordinating national contributions and distributing costs equitably in the face of uncertainty, inequality, and free-riding incentives. In an experimental setting, we distribute endowments unequally among a group of people who can reach a fixed target sum through successive money contributions, knowing that if they fail, they will lose all their remaining money with 50% probability. In some treatments, we give players the option to communicate intended contributions. We find that inequality reduces the prospects of reaching the target but that communication increases success dramatically. Successful groups tend to eliminate inequality over the course of the game, with rich players signaling willingness to redistribute early on. Our results suggest that coordination-promoting institutions and early redistribution from richer to poorer nations are both decisive for the avoidance of global calamities, such as disruptive climate change.

Energy requirements and carbon emissions for a low-carbon energy transition.

Achieving the Paris Agreement will require massive deployment of low-carbon energy. However, constructing, operating, and maintaining a low-carbon energy system will itself require energy, with much of it derived from fossil fuels. This raises the concern that the transition may consume much of the energy available to society, and be a source of considerable emissions. Here we calculate the energy requirements and emissions associated with the global energy system in fourteen mitigation pathways compatible with 1.5 °C of warming. We find that the initial push for a transition is likely to cause a 10-34% decline in net energy available to society. Moreover, we find that the carbon emissions associated with the transition to a low-carbon energy system are substantial, ranging from 70 to 395 GtCO2 (with a cross-scenario average of 195 GtCO2). The share of carbon emissions for the energy system will increase from 10% today to 27% in 2050, and in some cases may take up all remaining emissions available to society under 1.5 °C pathways.

Public versus private: does it matter for water conservation? Insights from California.

This article asks three connected questions: First, does the public view private and public utilities differently, and if so, does this affect attitudes to conservation? Second, do public and private utilities differ in their approaches to conservation? Finally, do differences in the approaches of the utilities, if any, relate to differences in public attitudes? We survey public attitudes in California toward (hypothetical but plausible) voluntary and mandated water conservation, as well as to price increases, during a recent period of shortage. We do this by interviewing households in three pairs of adjacent public and private utilities. We also survey managers of public and private urban water utilities to see if they differ in their approaches to conservation and to their customers. On the user side we do not find pronounced differences, though a minority of customers in all private companies would be more willing to conserve or pay higher prices under a public operator. No respondent in public utility said the reverse. Negative attitudes toward private operators were most pronounced in the pair marked by a controversial recent privatization and a price hike. Nonetheless, we find that California's history of recurrent droughts and the visible role of the state in water supply and drought management undermine the distinction between public and private. Private utilities themselves work to underplay the distinction by stressing the collective ownership of the water source and the collective value of conservation. Overall, California's public utilities appear more proactive and target-oriented in asking their customers to conserve than their private counterparts and the state continues to be important in legitimating and guiding conservation behavior, whether the utility is in public hands or private.

Isolated yet open: A metabolic analysis of Menorca.

Small islands are vulnerable to climate change, and at the same time contribute to local and global environmental problems with the intensification of tourist activities. Whereas there are many studies on the resource requirements or environmental impacts of small islands, there are few efforts to integrate information that is often analysed separately. Metabolic analysis, beyond quantifying biophysical flows, studies how society transforms these flows to reproduce the identity of the whole. This study applies the Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism (MuSIASEM) approach, to analyse the environmental and economic performance of different economic activities in the Mediterranean island of Menorca (Spain). The openness of the metabolic system (observed in the dependence on imports) and externalization of environmental impact are illustrated using the examples of the cheese and tourist industry. The results show that a higher economic performance in terms of value added is associated with activities in industry and services with a larger dependence on imports of "external resources" - fuel for transportation, milk for cheese, seasonal workers and "paying capacity" of tourists. This dependence reduces local environmental pressures and also adaptation capacity, since decisions made in Menorca may have limited impact elsewhere. Local agriculture depends less on external resources but it is limited by the low economic productivity of land and labour. An integrated analysis of the relations between metabolic rates and densities of flows in the different compartments of the society provides a holistic picture of sustainability issues and can contribute to decision-making by avoiding partial information.

Biodiversity policy beyond economic growth.

Increasing evidence-synthesized in this paper-shows that economic growth contributes to biodiversity loss via greater resource consumption and higher emissions. Nonetheless, a review of international biodiversity and sustainability policies shows that the majority advocate economic growth. Since improvements in resource use efficiency have so far not allowed for absolute global reductions in resource use and pollution, we question the support for economic growth in these policies, where inadequate attention is paid to the question of how growth can be decoupled from biodiversity loss. Drawing on the literature about alternatives to economic growth, we explore this contradiction and suggest ways forward to halt global biodiversity decline. These include policy proposals to move beyond the growth paradigm while enhancing overall prosperity, which can be implemented by combining top-down and bottom-up governance across scales. Finally, we call the attention of researchers and policy makers to two immediate steps: acknowledge the conflict between economic growth and biodiversity conservation in future policies; and explore socioeconomic trajectories beyond economic growth in the next generation of biodiversity scenarios.

Why environmentalists eat meat.

Why do people who care about the environment adopt behaviours that are not consistent with their beliefs? Previous studies approach this as a case of cognitive dissonance, researchers looking into the strategies through which people reduce gaps between their attitudes and their behaviours. Here we start from the premise that there is no dissonance, and that people have consistent reasons of why they are doing what they are doing. The research task is then to shed light on these reasons. Using Q-methodology, a mixed quantitative-qualitative approach, we interviewed 42 environmentally-minded researchers asking them why they eat meat. Our interviewees were aware of and cared about the environmental and ethical impacts of meat eating, but reasoned that they eat meat because either technological, or political changes are more important than what they personally do, because of doubts about the impact of personal action in a complex world, or simply because they lack the determination to stop eating meat. Our analysis suggests that policies and messages that try to educate or guilt meat-eaters are unlikely to work with those well aware of the impacts of their actions.

Radical dematerialization and degrowth.

The emission targets agreed in Paris require a radical reduction of material extraction, use and disposal. The core claim of this article is that a radical dematerialization can only be part and parcel of degrowth. Given that capitalist economies are designed to grow, this raises the question of whether, and under what circumstances, the inevitable 'degrowth' can become socially sustainable. Three economic policies are discussed in this direction: work-sharing, green taxes and public money.This article is part of the themed issue 'Material demand reduction'.