Social dimensions of fertility behavior and consumption patterns in the Anthropocene.

We consider two aspects of the human enterprise that profoundly affect the global environment: population and consumption. We show that fertility and consumption behavior harbor a class of externalities that have not been much noted in the literature. Both are driven in part by attitudes and preferences that are not egoistic but socially embedded; that is, each household's decisions are influenced by the decisions made by others. In a famous paper, Garrett Hardin [G. Hardin, Science 162, 1243-1248 (1968)] drew attention to overpopulation and concluded that the solution lay in people "abandoning the freedom to breed." That human attitudes and practices are socially embedded suggests that it is possible for people to reduce their fertility rates and consumption demands without experiencing a loss in wellbeing. We focus on fertility in sub-Saharan Africa and consumption in the rich world and argue that bottom-up social mechanisms rather than top-down government interventions are better placed to bring about those ecologically desirable changes.

Climate concern and policy acceptance before and after COVID-19.

It remains unclear how COVID-19 has affected public engagement with the climate crisis. According to the finite-pool-of-worry hypothesis, concern about climate change should have decreased after the pandemic, in turn reducing climate-policy acceptance. Here we test these and several other conjectures by using survey data from 1172 Spanish participants who responded before and after the first wave of COVID-19, allowing for both aggregate and within-person analyses. We find that on average climate concern has decreased, while acceptance of most climate policies has increased. At the individual-level, adverse health experiences are unrelated to these changes. The same holds for negative economic experiences, with the exception that unemployment is associated with reduced acceptance of some policies. Complementary to the finite-pool-of-worry test, we examine three additional pandemic-related issues. As we find, (1) higher climate concern and policy acceptance are associated with a belief that climate change contributed to the COVID-19 outbreak; (2) higher policy acceptance is associated with a positive opinion about how the government addressed the COVID-19 crisis; (3) citizens show favorable attitudes to a carbon tax with revenues used to compensate COVID-19-related expenditures. Overall, we conclude there is support for addressing the global climate crisis even during a global health crisis.

Environmental problem shifting from climate change mitigation: A mapping review.

Climate change mitigation will trigger major changes in human activity, energy systems, and material use, potentially shifting pressure from climate change to other environmental problems. We provide a comprehensive overview of such "environmental problem shifting" (EPS). While there is considerable research on this issue, studies are scattered across research fields and use a wide range of terms with blurred conceptual boundaries, such as trade-off, side effect, and spillover. We identify 506 relevant studies on EPS of which 311 are empirical, 47 are conceptual-theoretical, and 148 are synthetic studies or reviews of a particular mitigation option. A systematic mapping of the empirical studies reveals 128 distinct shifts from 22 categories of mitigation options to 10 environmental impacts. A comparison with the recent IPCC report indicates that EPS literature does not cover all mitigation options. Moreover, some studies systematically overestimate EPS by not accounting for the environmental benefits of reduced climate change. We propose to conceptually clarify the different ways of estimating EPS by distinguishing between gross, net, and relative shifting. Finally, the ubiquity of EPS calls for policy design which ensures climate change mitigation that minimizes unsustainability across multiple environmental dimensions. To achieve this, policymakers can regulate mitigation options-for example, in their choice of technology or location-and implement complementary environmental policies.

Prioritize carbon pricing over fossil-fuel subsidy reform.

While many climate activist groups enthusiastically advocate for the removal of fossil-fuel subsidies, we argue that this overstates both the climate effectiveness and political feasibility of such a strategy. Through synthesizing information from various global studies, we show that subsidies contribute to a relatively small portion of climate change and local externality problems, likely accounting for around 1%. We further argue that reform of fossil-fuel subsidies is hampered by various political and social factors, more so than the diffusion of carbon pricing. Based on these results, we argue that the far greater problem of unpriced externalities warrants a redirection or expansion of the enthusiasm for subsidy reform toward carbon pricing. This makes sense also as subsidy reform and carbon pricing essentially represent two sides of the same coin since both contribute to climate mitigation by raising fossil-fuel prices.

Respondent uncertainty in contingent valuation of preventing beach erosion: an analysis with a polychotomous choice question.

Respondent uncertainty is often considered as one of the main limitations of stated preference methods, which are nowadays being widely used for valuing environmental goods and services. This article examines the effect of respondent uncertainty on welfare estimates by applying the contingent valuation method. This is done in the context of beach protection against erosion. Respondent certainty levels are elicited using a five-category polychotomous choice question. Two different uncertainty calibration techniques are tested, namely one that treats uncertain responses as missing and another in which uncertain 'yes' responses are recoded as 'no' responses. We found no evidence that the former technique offers any gains over the conventional model assuming certainty. The latter calibration technique systematically reduces welfare estimates. The reduction is statistically significant only when the most certain 'yes' responses are recoded as 'no' responses. The article further identifies determinants of respondent uncertainty. Finally, it explores how real market experience affects respondent uncertainty.

Tired of climate targets? Shift focus of IPCC scenarios from emission and growth targets to policies.

Climate change has revived the debate on growth-versus-environment. In line with this, recently it has been proposed to shift the target focus of IPCC scenarios from emissions to post-growth. We argue here that this confounds ends and means, since while reduction of growth may be an outcome of good climate policies, it should not be a goal in itself. In fact, a post- or degrowth goal would mean an ineffective and costly way to reduce emissions. Instead, we suggest that the debate about pursuing economic growth versus achieving climate goals will become more transparent and policy-relevant through refocusing scenarios from targets to policy.

Public expectations about the impact of COVID-19 on climate action by citizens and government.

Since the onset of the COVID-19 crisis many have opinionated on how it may affect society's response to climate change. Two key questions here are how COVID-19 is expected to influence climate action by citizens and by the government. We answer these by applying topic modelling to textual responses from a survey of Spanish citizens. The identified topics tend to be more negative than positive, and more optimistic concerning future climate action by citizens. Positive views involve increasing pro-environmental behavior and are more common among younger, higher educated and male respondents as well as among those who perceive climate change as a serious threat or positively assessed COVID-19 confinement. Negative topics express concern that financial resources for climate action will be limited due to a focus on healthcare and economic recovery. In addition, they mention government mismanagement and waste due to use of protective measures like masks and gloves as impediments to effective climate action.

Earth stewardship: Shaping a sustainable future through interacting policy and norm shifts.

Transformation toward a sustainable future requires an earth stewardship approach to shift society from its current goal of increasing material wealth to a vision of sustaining built, natural, human, and social capital-equitably distributed across society, within and among nations. Widespread concern about earth's current trajectory and support for actions that would foster more sustainable pathways suggests potential social tipping points in public demand for an earth stewardship vision. Here, we draw on empirical studies and theory to show that movement toward a stewardship vision can be facilitated by changes in either policy incentives or social norms. Our novel contribution is to point out that both norms and incentives must change and can do so interactively. This can be facilitated through leverage points and complementarities across policy areas, based on values, system design, and agency. Potential catalysts include novel democratic institutions and engagement of non-governmental actors, such as businesses, civic leaders, and social movements as agents for redistribution of power. Because no single intervention will transform the world, a key challenge is to align actions to be synergistic, persistent, and scalable.

Governance in the Face of Extreme Events: Lessons from Evolutionary Processes for Structuring Interventions, and the Need to Go Beyond.

The increasing frequency of extreme events, exogenous and endogenous, poses challenges for our societies. The current pandemic is a case in point; but "once-in-a-century" weather events are also becoming more common, leading to erosion, wildfire and even volcanic events that change ecosystems and disturbance regimes, threaten the sustainability of our life-support systems, and challenge the robustness and resilience of societies. Dealing with extremes will require new approaches and large-scale collective action. Preemptive measures can increase general resilience, a first line of protection, while more specific reactive responses are developed. Preemptive measures also can minimize the negative effects of events that cannot be avoided. In this paper, we first explore approaches to prevention, mitigation and adaptation, drawing inspiration from how evolutionary challenges have made biological systems robust and resilient, and from the general theory of complex adaptive systems. We argue further that proactive steps that go beyond will be necessary to reduce unacceptable consequences.

Carbon tax acceptability with information provision and mixed revenue uses.

Public acceptability of carbon taxation depends on its revenue use. Which single or mixed revenue use is most appropriate, and which perceptions of policy effectiveness and fairness explain this, remains unclear. It is, moreover, uncertain how people's prior knowledge about carbon taxation affects policy acceptability. Here we conduct a survey experiment to test how distinct revenue uses, prior knowledge, and information provision about the functioning of carbon taxation affect policy perceptions and acceptability. We show that spending revenues on climate projects maximises acceptability as well as perceived fairness and effectiveness. A mix of different revenue uses is also popular, notably compensating low-income households and funding climate projects. In addition, we find that providing information about carbon taxation increases acceptability for unspecified revenue use and for people with more prior tax knowledge. Furthermore, policy acceptability is more strongly related to perceived fairness than to perceived effectiveness.

Environmental harm of hidden subsidies: global warming and acidification.

We investigate environmental impacts of off-budget or indirect subsidies, which, unlike on-budget subsidies, are not visible in government budgets. Such subsidies have received little attention in economic and environmental research, even though they may be at least as important from an environmental perspective as on-budget subsidies. We offer a typology of indirect subsidies. Next, we estimate the magnitude of these subsidies and their impact on greenhouse gas (GHG) and acidifying emissions for the agriculture, energy, and transport sectors in The Netherlands. The calculations are based on a model approach that translates a particular subsidy into price and quantity changes using empirical elasticities, followed by environmental effect estimates using pollution-intensity parameters. The various environmental pollution effects are aggregated into environmental indicators. The results show, among others, that GHG emissions caused by off-budget subsidies contribute to more than 30% of the policy targets specified by the Kyoto Protocol for CO2 emissions reduction by The Netherlands. Reforming or removing off-budget subsidies may thus be an important strategy of effective climate policy.

Trade-based estimation of bluefin tuna catches in the Eastern Atlantic and Mediterranean, 2005-2011.

The Eastern Atlantic and Mediterranean stock of Bluefin tuna Thunnus thynnus (BFTE) has long been considered overfished and at risk of collapse. Although ICCAT quotas for this stock have decreased considerably over the past years, uncertainty exists about the degree of catch beyond this quota. The extent of such catch is an important piece of information in stock assessment models as well as being an indicator of the effectiveness of fisheries management. We present a model using Bluefin tuna trade data to infer actual catches. Basing our calculations on 25 countries involved in BFTE trade, we estimate that between 2005 and 2011, allowable quotas were exceeded by 44 percent. This gap between catch and quotas has slightly increased over past years, leading to estimated excess catches of 57 percent for the period between 2008 and 2011. To improve assessments, preparation and design of BFTE management, we suggest that the estimated total removals reported in this paper be included in stock assessment models for BFTE. An implication of our findings is that ICCAT member states should take stronger measures to monitor and enforce compliance with quotas.