The forward-looking significance of the 2015 Paris Agreement is explored in the context of the global ecological crisis and its local manifestations. The agreement is considered as an experimentalist treaty that depends upon overarching goals, autonomous actors and iterative learning processes. It originated in efforts by UNFCCC parties, enabled by the EU, to find a way to make collective progress on climate change in the absence of a global ‘hegemon’, while being bedevilled by issues surrounding power, competition and willingness to pay. The implications of the global mitigation (temperature) and adaptation (process) goals are explored, and the systems established for attempting and reporting on them are explained. The design and content of the rest of the book are outlined.

Some 10,000 years ago, agriculture arose independently in several areas across the world. The causes of the agricultural transition are still debated, but it is likely that the unprecedented warmth and stability of the Holocene climate made agriculture possible and that the climate instability of the Pleistocene made it impossible. As the weather became more predictable, people began to more intensively manage wild plants and began to store the grain they collected. Because of the unpredictability of harvests, people cultivated more crops than they thought they would need, and in most years, there was a surplus of food, leading to larger and more concentrated populations. By 5,000 years ago, small-scale agriculture had led to large-scale state-managed economies and total dependence on agriculture. Competition between city-states gave us full-blown ultrasocial economies and hierarchical, repressive states. Other consequences of agriculture for individuals include a marked decline in physical health, a reduction in brain size, and a loss of individual autonomy.

Given global social and environmental change, understanding how resulting place change affects people–place bonds is of pressing importance. However, given traditional views of these bonds as static, understanding the fluidity of people’s relationship with place remains nascent. We examine how people’s sense of place relating to Australia’s Great Barrier Reef changed over a four-year period during which the reef suffered climate-change-induced mass coral bleaching. Operationalising sense of place with seven indicators representing place attachment, identity and meanings, we found increases in attachment, identity and two meanings (pride, biodiversity) and decreases in three meanings (lifestyle, aesthetics, scientific value). We suggest that place change heightened the emotional and intangible elements of sense of place, while having a negative effect on the more instrumental meanings. Our results challenge a notion of people–place bonds premised on fixity, stability, and low dimensionality, instead suggesting the need to consider them as dynamic and multidimensional.

Many of the dramatic changes across the planet during the Anthropocene Epoch cannot be reversed within our lifespans, so it becomes imperative to adapt to change as far as possible. According to the IPCC, adaptation is ‘the process of adjustment to actual or expected climate and its effects. In human systems, adaptation seeks to moderate or avoid harm or exploit beneficial opportunities. In some natural systems, human intervention may facilitate adjustment to expected climate and its effects’ (1, p. SPM 5). While this definition refers only to climate, the context in which adaptation has been most thoroughly considered, the concept of adaptation is applicable to the full range of planetary changes. As implied by the IPCC definition, an adaptation action might be taken proactively, to reduce harm in advance of an impact, or reactively, in response to a perceived or real health risk.

While climate change is a vitally important environmental change confronting humanity, the planet is changing in other unprecedented ways. Many of these changes – pollution, biodiversity loss, land use changes, and others – correspond to the planetary boundaries introduced in Chapter 1. Like climate change, these planetary changes also have implications for human health and well-being – the subject of this chapter. We turn first to pollution, a broad category that includes air and water pollution by substances including metals, pesticides, plastics, and pharmaceuticals. Next we consider land use and biodiversity loss – two closely intertwined processes. After land we turn to freshwater – exploring the many ways in which humans have altered the planet’s hydrology. Finally, we explore how these many changes interact with each other in complex ways.

Chapter 11 examines the rapid increases in wildfire extent and the role played by increased temperature-induced evaporative demand. The story begins in early November 2018, with the author clearing bone-dry brush in the woods behind his house, and discussing these incredibly dry conditions on a local radio show with his local volunteer firefighter friends. In dry regions, warmer air's increased ability to hold water increases its capacity to draw moisture from soils and plants. On November 6, the Community Alert show discussed the exceptionally dry conditions across California, and how these dry-fuel conditions were expected to combine with high winds to set the stage for potential conflagration. At sunrise on November 8, the Camp Fire, California's deadliest and costliest conflagration, broke out. Since the early 1980s, annual US wildfire extents have increased by more than 300 percent. In California, 2017 and 2018 wildfire extent, deaths, and damages were staggering. Increases in western US wildfire extent are tightly coupled with increases in aridity, which are related to both increases in air temperatures and atmospheric water demand. The 2017 and 2018 US wildfires were associated with more than $40 billion in damages and more than a hundred fatalities. Chapter 11 concludes with a firsthand account from Laura Eilerts, a ninety-one-year-old woman who lost her house in the Paradise Fire and drove herself to safety.

This chapter profiles contemporary examples of ecosystem collapse and recovery. Case studies presented include coral reefs, marine fisheries, freshwater ecosystems (streams, rivers and lakes), forests (including tropical, temperate and boreal), savanna, and temperate agroecosystems. In each case, the available empirical evidence is reviewed in relation to the ecological mechanisms underlying both ecosystem collapse and recovery. At the end of the chapter, the theoretical propositions identified in Chapter 2 and refined in Chapter 3 are then evaluated in the light of the evidence available from these contemporary case studies.

Cross-cutting issues

GEO-6 identifies three key socioeconomic systems with far-reaching environmental impacts: the food, energy and waste systems (well established). These systems are closely interlinked. The processes of producing, distributing and using both food and energy, and materials in general, generates significant waste. These processes and the waste they generate pollute the environment. They also impact biodiversity and ecosystems. Transformative change in these systems will require policy coherence and synergies implicitly addressing issues related to air and freshwater quality, land and soil degradation, oceans and coast integrity, and biodiversity loss. ﹛Chapter 17, ExecSum, 17.3.2, 17.4.3, 17.5.1﹜

Food

The current food system is inadequately providing nourishment to millions of people in the world, while it is responsible for major diet-related diseases in millions of others (well established). Over 800 million people are undernourished and more than 2 billion suffer from micronutrient deficiencies. Patterns of inequity in access to food correspond to other social inequities, including those based on gender, age, class and the marginalization of racial and ethnic groups. At the same time, 39 per cent of the global adult population (1.9 billion people) is overweight and 13 per cent (650 million people) is obese (World Health Organization [WHO] 2018a). Diet-related diseases such as type 2 diabetes, colorectal cancer and cardiovascular disease are globally pervasive and, especially in rich countries, associated with overconsumption of saturated fats and processed foods. These diseases are becoming increasingly prevalent in LMICs as animal protein, and products high in fats and sugars, become more widely available and affordable. ﹛4.4.3﹜

Demand for food from land and the sea is growing, with impacts on the planet and human health. Feeding a growing population of 9-10 billion by 2050, in the context of climate change and without making environmental degradation and social problems worse, is a key challenge (well established). Current land and ocean management and food production practices cannot achieve this goal and also prevent the loss of natural capital, preserve ecosystem services, combat climate change, address energy and water security, and promote gender and social equality (established but incomplete). (SDG 12) The proportion of the global population living in low-income food-deficit countries (LIFDCs) rose from 72 per cent in 1965 to 80 per cent in 2005.

The sixth Global Environment Outlook (GEO-6) assesses the state of the environment, the effectiveness of policy and other responses in addressing environmental challenges, and the possible pathways for achieving various internationally agreed environmental goals. It differs from and complements other global assessments (see Annex 1) in its scope and integrated nature. GEO-6 is more holistic in its analysis, whereas other assessments tend to focus more narrowly on, for example, biodiversity and ecosystem services (the Intergovernmental Science- Policy Platform on Biodiversity and Ecosystem Services [IPBES]), climate change (the Intergovernmental Panel on Climate Change [IPCC]) or the marine environment (the World Ocean Assessment).

The GEO-6, entitled Healthy Planet, Healthy People (United Nations Environment Programme [UNEP] 2019a) and its Summary for Policymakers (UNEP 2019b), provides evidence-based environmental information to help policymakers and other decision makers to achieve the environmental mandates of the 2030 Agenda for Sustainable Development (Agenda 2030) and its Sustainable Development Goals (SDGs), together with other internationally agreed environmental goals, as well as to implement multilateral, regional and global environmental agreements. The theme Healthy Planet, Healthy People links the environmental dimension of the SDGs to their human and social dimensions. GEO-6 assesses recent scientific knowledge and data, analyses current and past environmental policies (including their objectives and consequences), and identifies options to achieve sustainable development by 2050. ﹛Chapter 1; Summary for Policymakers [SPM]﹜. This explains why there have been changes in the context, focus and methods of GEO-6 compared with previous GEOs.

This Technical Summary synthesizes the key evidence and messages of GEO-6. Chapter 1 sets out the context and methodological approach of the GEO-6 assessment. It is followed by chapters that:

• ❖ discuss the five drivers affecting the health of the planet: trends in human population, combined with economic development; growth of consumption; rapid urbanization; accelerating technological innovation; and climate change (Chapter 2);

• ❖ review the impacts of broad systemic activities (called cross-cutting issues in the GEO-6) and the health, equity and economic dimensions of these impacts (Chapter 3); collectively providing evidence that the planet is becoming increasingly unhealthy;.

• ❖ review the literature and undertake case studies on policy implementation to show how policies are struggling to keep up with the rate and scale of planetary degradation (Chapter 4);