A widely held belief is that once the impacts of warming are experienced more directly and substantially, especially by affluent populations, the necessary support for a politics prioritising ambitious emissions reductions will follow. But consideration of the indirect socioeconomic impacts of warming suggests this could be false hope.

There is some evidence to support the common intuition that, as the direct impacts of warming intensify – particularly in the affluent Global North – a politics ambitious enough to confront the climate emergency may finally find support. However, it seems at least equally likely that the opposite trend will prevail. This proposition can be understood by considering various indirect impacts of warming, including the widening of socioeconomic inequalities (within and between countries), increases in migration (intra- and inter-nationally) and heightened risk of conflict (from violence and war through to hate speech and crime). Compiling these impacts reveals a considerable and highly inconvenient overlap with key drivers of the authoritarian populism that has proliferated in the 21st century. It highlights the risk of a socio-ecological feedback loop where the consequences of warming create a political environment entirely at odds with that required to reduce emissions. Such a future is, of course, far from inevitable. Nonetheless, the risks highlight the urgent need to find public support for combined solutions to climate change and inequality, which go well beyond the status-quo. This is necessary not only for reasons of economic and climate justice, but in order to mitigate political barriers to carbon mitigation itself.

As the impacts of warming are experienced more directly and substantially, we may vote for precisely the wrong people.

Coastal communities face environmental challenges that put food, energy, and water systems at risk. Although highly interdependent, it is unknown the extent to which coastal resilience research has considered interactions among food–energy–water systems. Twenty peer-reviewed articles were identified that focused on these systems and coastal resilience. Although a nexus approach was not employed universally, these studies most commonly addressed interactions among these systems related to acute hazards. They consistently acknowledged the influence of energy and transportation systems upon the others. As such, planners should incorporate linkages across all three systems during coastal resilience planning especially in relation to acute hazards.

Coastal communities strive for resilience in the face of an ever-growing suite of threats by planning and preparing for numerous uncertain futures. Food, energy, and water systems are highly interconnected and essential to the well-being of coastal communities. However, it is unknown the extent to which coastal resilience research has included food–energy–water nexus considerations. This study used a systematic literature review of peer-reviewed research articles and identified 20 studies that focused on food, energy, and water systems as related to coastal resilience. Results revealed four main findings: (1) the food–energy–water nexus approach was most commonly applied to coastal resilience in the study of US locations and in the context of acute hazards, (2) a direct food–energy–water or other nexus approach was directly employed by only half of the studies, however, all highlighted the relevance of systems interconnections in the context of coastal resilience, (3) the energy system was shown to impact every system to which it was connected, and (4) the transportation system was also shown to impact every system to which it was connected, which suggests that the food–energy–water nexus should be expanded to include transportation systems.

Coastal resilience and food–energy–water nexus literature synthesis finds interconnected systems considerations relevant to resilience.

The thesis of this paper is that the COVID-19 crisis creates opportunities for fundamental change towards a more sustainable economy, for two reasons: structural change in the economy and a change in public opinion. The paper identifies how the COVID-19 crisis accelerates six processes of change that can be leveraged in policy making. With a focus on the Netherlands, it argues for activist government policy because of the tipping-point nature of the economic system in the crisis.

Structural change in the economy and a change in public opinion during the COVID-19 crisis jointly imply that government choices regarding investments, regulation and taxes can now create stronger synergies of cleaner economic growth and employment creation with ecological, social and financial sustainability. The paper details this for six areas, with examples taken from The Netherlands. High levels of private and (in some countries) public debt may become so unsustainable that this prompts a restructuring of financing systems which are more productive and more in support of ecological goals. In value chains, ICT systems and urban transport systems, forced changes such as more work from home, more cycling lanes and more local production may, once in place, be used as proof of concepts for permanently different infrastructures and organizations. Aviation and energy became dependent on public support, which created financial leverage for enforcing change.

COVID-19 creates opportunities for change towards sustainability as it accelerates six processes of change.

Improving the flow of information between governments and local communities is paramount to achieving effective climate change mitigation and adaptation. We propose five pathways to deepen participation and improve community-based climate action. The pathways can be summarized as visualization, simulations to practice decision-making, participatory budgeting and planning, environmental civic service, and education and curriculum development. These pathways contribute to improving governance by consolidating in governments the practice of soliciting and incorporating community participation while simultaneously giving communities the tools and knowledge needed to become active contributors to climate change adaptation and mitigation measures.

Community participation is considered a key component in the design of responses to climate change. Substantial engagement of local communities is required to ensure information flow between governments and communities, but also because local communities are the primary sites of adaptation action. However, frontline communities are often excluded from decision-making and implementation processes due to political choices or failures to identify ways to make participatory frameworks more inclusive. Climate action requires the active engagement of communities in making consequential decisions, or what we term deepened participation. We propose five pathways to deepen participation: visualization, simulations to practice decision-making, participatory budgeting and planning, environmental civic service, and education and curriculum development. The five pathways identify strategies that can be incorporated into existing organizational and institutional frameworks or used to create new ones. Shortcomings related to each strategy are identified. Reflection by communities and governments is encouraged as they choose which participatory technique(s) to adopt.

Climate action requires the active engagement of communities. Learn five pathways to get started deepening participation.

As green spaces, lawns are often thought to capture carbon from the atmosphere. However, once mowing, fertlising and irrigation are taken into account, we show that they become carbon sources, at least in the long run. Converting unused urban and rural lawn and grassland to treescapes can make a substantial contribution to reducing greenhouse gas emissions and increasing carbon absorption from the atmosphere. However, it is imperative for governing bodies to put in place appropriate policies and incentives in order to achieve this.

Mown grass or lawn is a ubiquitous form of vegetation in human-dominated landscapes and it is often claimed to perform an ecosystem service by sequestering soil carbon. If lawn maintenance is included, however, we show that lawns become net carbon emitters. We estimate that globally, if one-third of mown grass in cities was returned to treescapes, 310–1630 million tonnes of carbon could be absorbed from the atmosphere, and up to 43 tonnes of carbon equivalent per hectare of emissions could be avoided over a two-decade time span. We therefore propose that local and central governments introduce policies to incentivise and/or regulate the conversion of underutilised grass into treescapes.

If unused lawns were planted with trees, a gigaton of carbon could be removed from the atmosphere over two decades.

Integrated assessment models (IAMs) are important scientific tools for advising policymakers and the public on climate mitigation. Recent results of modeling exercises relied upon large amounts of techniques that can capture carbon dioxide from the atmosphere, undoing current and past emissions. I argue that the reliance on such techniques unduly shifts risk to future generations and away from current high emitting countries. From an ethical point of view, this is problematic. IAM studies need to be more explicit about the value positions that evidence of mitigation pathways depends upon and should represent a wider array of plausible value positions.

This paper analyzes the nonepistemic value judgments involved in modeling Carbon Dioxide Removal (CDR) techniques. The comparably high uncertainty of these techniques gives rise to epistemic risk when large-scale CDR is relied upon in most scenario evidence. Technological assumptions on CDR are thus entangled with nonepistemic value judgments. In particular, the reliance on large-scale CDR implies shifting risk to future generations and thereby gives a one-sided answer to questions of intergenerational justice. This bias in integrated assessment modeling is problematic given the policy-advising role of integrated modeling. Modeling climate mitigation should focus on transforming these implicit value positions into explicit scenario parameters and should aim to provide scenario evidence on the complete array of value-laden mitigation strategies.

The ethics of mitigation pathways, for example in relation to CDR, must be made transparent and plural.

Globalisation has narrowed the gap between producers and consumers. Nations are increasingly relying on commodities produced outside of their borders for satisfying their consumption. This is particularly the case for the European Union (EU). This study assesses spillover effects, i.e. impacts taking place outside of the EU borders, resulting from the EU's demand for food products, in terms of environmental and social indicators.

Human demand for agri-food products contributes to environmental degradation in the form of land-use impacts and emissions into the atmosphere. Development and implementation of suitable policy instruments to mitigate these impacts requires robust and timely statistics at sectoral, regional and global levels. In this study, we aim to assess the environmental and social impacts embodied in European Union's (EU's) demand for agri-food products. To this end, we select a range of indicators: emissions (carbon dioxide, particulate matter, sulphur dioxide, nitrous oxide), land use, employment and income. We trace these environmental and social impacts across EU's trading partners to identify specific sectors and regions as hotspots of international spillovers embodied in EU's food supply chains and find that these hotspots are wide-ranging in all continents. EU's food demand is responsible for 5% of the EU's total CO2 consumption-based footprint, 9% of the total NOX footprint, 16% of the total PM footprint, 6% of the total SO2 footprint, 46% of the total land-use footprint, 13% of the total employment footprint and 5% of the total income footprint. Our results serve to inform future reforms in the EU for aligning policies and strategies with the Sustainable Development Goals (SDGs) and the objectives of the Paris Climate Agreement.

Significant environmental and social spillover effects embodied in the EU's food supply chains.

Cities in the distant past – as documented by archaeologists and historians – provide an extensive record of urban successes and failures, yet this information has had little impact on the field of sustainability science. I explore two reasons for this situation. First, these scholars have often failed to synthesize their data scientifically, and, second, they have not approached the transfer of past knowledge to present research in a rigorous manner. I organize discussion of these issues around three arguments for the present value of past cities: the urban trajectory argument, the sample size argument, and the laboratory argument.

I explore the different ways historical and archaeological data can be deployed to contribute to research on urban sustainability science, emphasizing issues of argumentation and epistemology. I organize the discussion around three types of argument. The urban trajectory argument exploits the long time series of early cities and urban regions to examine change at a long time scale. The sample size argument views the role of early cities as adding to the known sample of settlements to increase understanding of urban similarities and differences. The laboratory argument uses data from past cities to explicitly test models derived from contemporary cities. Each argument is examined for three contrasting epistemological approaches: heuristic analogs, case studies, and quantitative studies. These approaches form a continuum leading from lesser to greater scientific rigor and from qualitative to quantitative frameworks. Much past-to-present argumentation requires inductive logic, also called reasoning by analogy. Sustainability scientists have confused this general form of argument with its weakest version, known as heuristic analogs. I stress ways to improve methods of argumentation, particularly by moving research along the continuum from weaker to stronger arguments.

Better methods of argument allow the past record of urban success and failure to contribute to urban sustainability science.

This paper expands the range of scenarios usually explored in integrated assessment models by exploring unconventional economic scenarios (steady-state and degrowth) and assuming no use of negative emissions. It is shown, using a mathematical model of climate and economy, that keeping cumulative emissions within the 1.5 degree carbon budget is possible under all growth assumptions, assuming a rapid electrification of end use and an immediate upscaling of renewable energy investments. Under business-as-usual investment assumptions no economic trajectory corresponds with emissions reductions consistent with the 1.5 degree carbon budget.

This paper presents a stock-flow consistent input–output integrated assessment model designed to explore the dual dynamics of transitioning to renewable energy while electrifying end use subject a carbon budget constraint. Unlike the majority of conventional integrated assessment model analyses, this paper does not assume the deployment of carbon dioxide removal and examines the role that alternative economic pathways (steady-states and degrowth) may play in achieving 1.5°C consistent emissions pathways. The model is internally calibrated based on a life-cycle energy return on investment scheme and the energy transition dynamics are captured via a dynamic input–output formulation. Renewable energy investment as a fraction of gross domestic product for successful emissions pathways reaches 5%. In terms of new capital requirements and investments, degrowth trajectories impose lower transition requirements than steady-state and growth trajectories.

We explore the role that steady-state and degrowth economic trajectories may play in emissions reductions consistent with a 1.5 degree world..