A just world on a safe planet: a Lancet Planetary Health–Earth Commission report on Earth-system boundaries, translations, and transformations

The health of the planet and its people are at risk. The deterioration of the global commons—ie, the natural systems that support life on Earth—is exacerbating energy, food, and water insecurity, and increasing the risk of disease, disaster, displacement, and conflict. In this Commission, we quantify safe and just Earth-system boundaries (ESBs) and assess minimum access to natural resources required for human dignity and to enable escape from poverty. Collectively, these describe a safe and just corridor that is essential to ensuring sustainable and resilient human and planetary health and thriving in the Anthropocene. We then discuss the need for translation of ESBs across scales to inform science-based targets for action by key actors (and the challenges in doing so), and conclude by identifying the system transformations necessary to bring about a safe and just future. Our concept of the safe and just corridor advances research on planetary boundaries and the justice and Earth-system aspects of the Sustainable Development Goals. We define safe as ensuring the biophysical stability of the Earth system, and our justice principles include minimising harm, meeting minimum access needs, and redistributing resources and responsibilities to enhance human health and wellbeing. The ceiling of the safe and just corridor is defined by the more stringent of the safe and just ESBs to minimise significant harm and ensure Earth-system stability. The base of the corridor is defined by the impacts of minimum global access to food, water, energy, and infrastructure for the global population, in the domains of the variables for which we defined the ESBs. Living within the corridor is necessary, because exceeding the ESBs and not meeting basic needs threatens human health and life on Earth. However, simply staying within the corridor does not guarantee justice because within the corridor resources can also be inequitably distributed, aggravating human health and causing environmental damage. Procedural and substantive justice are necessary to ensure that the space within the corridor is justly shared. We define eight safe and just ESBs for five domains—the biosphere (functional integrity and natural ecosystem area), climate, nutrient cycles (phosphorus and nitrogen), freshwater (surface and groundwater), and aerosols—to reduce the risk of degrading biophysical life-support systems and avoid tipping points. Seven of the ESBs have already been transgressed: functional integrity, natural ecosystem area, climate, phosphorus, nitrogen, surface water, and groundwater. The eighth ESB, air pollution, has been transgressed at the local level in many parts of the world. Although safe boundaries would ensure Earth-system stability and thus safeguard the overall biophysical conditions that have enabled humans to flourish, they do not necessarily safeguard everyone against harm or allow for minimum access to resources for all. We use the concept of Earth-system justice—which seeks to ensure wellbeing and reduce harm within and across generations, nations, and communities, and between humans and other species, through procedural and distributive justice—to assess safe boundaries. Earth-system justice recognises unequal responsibility for, and unequal exposure and vulnerability to, Earth-system changes, and also recognises unequal capacities to respond and unequal access to resources. We also assess the extent to which safe ESBs could minimise irreversible, existential, and other major harms to human health and wellbeing through a review of who is affected at each boundary. Not all safe ESBs are just, in that they do not minimise all significant harm (eg, that associated with the climate change, aerosol, or nitrogen ESBs). Billions of people globally do not have sufficient access to energy, clean water, food, and other resources. For climate change, for example, tens of millions of people are harmed at lower levels of warming than that defined in the safe ESB, and thus to avoid significant harm would require a more stringent ESB. In other domains, the safe ESBs align with the just ESBs, although some need to be modified, or complemented with local standards, to prevent significant harm (eg, the aerosols ESB). We examine the implications of achieving the social SDGs in 2018 through an impact modelling exercise, and quantify the minimum access to resources required for basic human dignity (level 1) as well as the minimum resources required to enable escape from poverty (level 2). We conclude that without social transformation and redistribution of natural resource use (eg, from top consumers of natural resources to those who currently do not have minimum access to these resources), meeting minimum-access levels for people living below the minimum level would increase pressures on the Earth system and the risks of further transgressions of the ESBs. We also estimate resource-access needs for human populations in 2050 and the associated Earth-system impacts these could have. We project that the safe and just climate ESB will be overshot by 2050, even if everybody in the world lives with only the minimum required access to resources (no more, no less), unless there are transformations of, for example, the energy and food systems. Thus, a safe and just corridor will only be possible with radical societal transformations and technological changes. Living within the safe and just corridor requires operationalisation of ESBs by key actors across all levels, which can be achieved via cross-scale translation (whereby resources and responsibilities for impact reductions are equitably shared among actors). We focus on cities and businesses because of the magnitude of their impacts on the Earth system, and their potential to take swift action and act as agents of change. We explore possible approaches for translating each ESB to cities and businesses via the sequential steps of transcription, allocation, and adjustment. We highlight how different elements of Earth-system justice can be reflected in the allocation and adjustment steps by choosing appropriate sharing approaches, informed by the governance context and broader enabling conditions. Finally we discuss system transformations that could move humanity into a safe and just corridor and reduce risks of instability, injustice, and harm to human health. These transformations aim to minimise harm and ensure access to essential resources, while addressing the drivers of Earth-system change and vulnerability and the institutional and social barriers to systemic transformations, and include reducing and reallocating consumption, changing economic systems, technology, and governance

Environmental issues along the United States-Mexico border. Drivers of change and responses of citizens and Iinstitutions

The US-Mexico border region illustrates the challenges of binational environmental management in the context of a harsh physical environment, rapid growth, and economic integration. Transboundary and shared resources and conflicts include limited surface water supplies, depletion of groundwater, air and water pollution, hazardous waste, and conservation of important natural ecosystems. Public policy responses to environmental problems on the border include binational institutions such as the IBWC, BECC and CEC, the latter two established in response to environmental concerns about the North American Free Trade Agreement (NAFTA). Environmental social movements and nongovernmental organizations have also become important agents in the region. These new institutions and social movements are especially interesting on the Mexican side of the border where political and economic conditions have often limited environmental enforcement and conservation, and where recent policy changes also include changes in land and water law, political democratization, and government decentralization

Food security and global environmental change: Emerging challenges

Most research linking global environmental change and food security focuses solely on agriculture: either the impact of climate change on agricultural production, or the impact of agriculture on the environment, e.g. on land use, greenhouse gas emissions, pollution and/or biodiversity. Important though food production is, many other factors also need to be considered to understand food security. A recent international conference on "Environmental Change and Food Security: Bridging Science, Policy and Development for Adaptation" included a range of papers that embraced the multiple dimensions of the food systems that underpin food security. The major conclusion from the conference was that technical fixes alone will not solve the food security challenge. Adapting to the additional threats to food security arising from major environmental changes requires an integrated food system approach, not just a focus on agricultural practices. Six key issues emerged for future research: (i) adapting food systems to global environmental change requires more than just technological solutions to increase agricultural yields; (ii) tradeoffs across multiple scales among food system outcomes are a pervasive feature of globalized food systems; (iii) within food systems, there are some key underexplored areas that are both sensitive to environmental change but also crucial to understanding its implications for food security and adaptation strategies; (iv) scenarios specifically designed to investigate the wider issues that underpin food security and the environmental consequences of different adaptation options are lacking; (v) price variability and volatility often threaten food security; and (vi) more attention needs to be paid to the governance of food systems

A non-consequentialist alternative to economics

Providing an up-to-date synthesis of knowledge relevant to the climate change issue, this book ranges from the basic science documenting the need for policy action to the technologies, economic instruments and political strategies that can be employed in response to climate change. Ethical and cultural issues constraining the societal response to climate change are also discussed. This book covers a very wide range of disciplines – core biophysical sciences involved with climate change (geosciences, atmospheric sciences, ocean sciences, ecology/biology) as well as economics, political science, health sciences, institutions and governance, sociology, ethics and philosophy, and engineering

Geomorphology and earth system science

Earth system science is an approach to obtain a scientific understanding of the entire Earth system on a global scale by describing how its component parts and their interactions have evolved, how they function, and how they may be expected to continue to evolve on all time-scales. The aim of this review is to introduce some key examples showing the role of earth surface processes, the traditional subject of geomorphology, within the interacting Earth system. The paper considers three examples of environmental systems in which geomorphology plays a key role: (i) links between topography, tectonics, and atmospheric circulation; (ii) links between geomorphic processes and biogeochemical cycles; and (iii) links between biological processes and the earth’s surface. Key research needs are discussed, including the requirement for better opportunities for interdisciplinary collaboration, clearer mathematical frameworks for earth system models, and more sophisticated interaction between natural and social scientists