Decarbonizing power grids is an essential pillar of global efforts to mitigate climate change impacts. Renewable energy generation is expected to play an important role in electricity decarbonization, although its variability and uncertainty are creating new flexibility challenges for electric grid operators that must match supply with constantly changing demand. Distributed energy resources (DERs)—including distributed generation, demand response, and distributed energy storage—can play an important role in providing the flexibility needed to integrate high penetrations of renewable energy. This article examines federal and state enabling policies and regulations for DER, market strategies and business models that have facilitated DER expansion, and key emerging challenges for DER in the United States. Based on a review of the US experience, the article offers lessons for other countries, focusing on the role and limits of policy, the facilitative role of utility regulatory reform, the need to balance different interests in tariff design, the benefits of DER participation in wholesale markets, and the importance of proactive interconnection policies.

The past century has been a time of unparalleled changes in global climate and global biogeochemistry. At the forefront of the study of these changes are regular time-series observations at remote stations of atmospheric CO2, isotopes of CO2, and related species, such as O2 and carbonyl sulfide (COS). These records now span many decades and contain a wide spectrum of signals, from seasonal cycles to long-term trends. These signals are variously related to carbon sources and sinks, rates of photosynthesis and respiration of both land and oceanic ecosystems, and rates of air-sea exchange, providing unique insights into natural biogeochemical cycles and their ongoing changes. This review provides a broad overview of these records, focusing on what they have taught us about large-scale global biogeochemical change.

Over the past few years, studies in political ecology and environmental justice have been increasingly connecting the commons and social movements empirically, giving shape to a new, distinctive body of research on commons movements. In our review, we first organize and synthesize empirical lessons from this body of literature. We then highlight recent theoretical efforts made by scholars to both bridge and transcend the gap between the theory of the commons and social movement theory. As we illustrate, movements can help create and strengthen commons institutions and discourses, as well as rescale them horizontally and vertically. This is particularly evident in the context of rural community-rights movements in the global South, as well as in new water and food commons movements and community energy movements in both the global South and North. Commons institutions, in turn, can serve as the basis of social mobilization and become a key frame for social movements, as shown in the context of local environmental justice and livelihoods conflicts and anti-privatization struggles. Tensions and contradictions of commons-movement dynamics also exist and reflect trade-offs between diversity versus uniformization and organizational closure versus expansion of discourses and practices. Theoretically, there is an opportunity to cross boundaries from the theory of the commons to social movementtheory and vice versa, e.g., by highlighting the role of political opportunities and framing, and biophysical factors and polycentricity, respectively. More importantly, a new commons movements theory is emerging focusing on cross-scalar organizations, the virtuous cycles between commons projects and mobilization, and the processes of commons-making.

The global food system faces major risks and threats that can cause massive economic loss; dislocation of food supply chains; and welfare loss of producers, consumers, and other food system actors. The interrelated nature of the system has highlighted the complexity of risks. Climate change, extreme weather events, and degradation and depletion of natural resources, including water, arable, forestry, and pastural lands, loss of biodiversity, emerging diseases, trade chokepoints and disruptions, macroeconomic shocks, and conflicts, can each seriously disrupt the system. Coincidence of these risks can compound the effects on global food security and nutrition. Smallholder farmers, rural migrants, women, youth, children, low-income populations, and other disadvantaged groups are particularly vulnerable. The coronavirus disease 2019 (COVID-19) pandemic exemplifies a perfect storm of coincidental risks. This article reviews major risks that most significantly impact food systems and highlights the importance of prospects for coincidence of risks. We present pathways to de-risk food systems and a way forward to ensure healthy, sustainable, inclusive, and resilient food systems.

We present an overview of the global spatiotemporal distribution of avian biodiversity, changes in our knowledge of that biodiversity, and the extent to which it is imperilled. Birds are probably the most completely inventoried large taxonomic class of organisms, permitting a uniquely detailed understanding of how the Anthropocene has shaped their distributions and conservation status in space and time. We summarize the threats driving changes in bird species richness and abundance, highlighting the increasingly synergistic interactions between threats such as habitat loss, climate change, and overexploitation. Many metrics of avian biodiversity are exhibiting globally consistent negative trends, with the International Union for Conservation of Nature's Red List Index showing a steady deterioration in the conservation status of the global avifauna over the past three decades. We identify key measures to counter this loss of avian biodiversity and associated ecosystemservices, which will necessitate increased consideration of the social context of bird conservation interventions in order to deliver positive transformative change for nature.

This review examines the alleged crisis of trust in environmental science and its impact on public opinion, policy decisions in the context of democratic governance, and the interaction between science and society. In an interdisciplinary manner, the review focuses on the following themes: the trustworthiness of environmental science, empirical studies on levels of trust and trust formation; social media, environmental science, and disinformation; trust in environmental governance and democracy; and co-production of knowledge and the production of trust in knowledge. The review explores both the normative issue of trustworthiness and empirical studies on how to build trust. The review does not provide any simple answers to whether trust in science is generally in decline or whether we are returning to a lessenlightened era in public life with decreased appreciation of knowledge and truth. The findings are more nuanced, showing signs of both distrust and trust in environmental science.

Qualitative research methods examine a wide range of topics in the study of environment and resource management. This first review on the topic highlights innovative and impactful research over the past few decades, drawing from social science disciplines that include sociology, geography, anthropology, political science, public policy, and psychology. We describe qualitative research methods that have addressed five scientific goals: ( a) describing what the world is like, ( b) predicting what the world can be like, ( c) acknowledging researcher positionality, reflexivity, and diversifying ways of knowing in theorizing and research designs, ( d) integrating imaginaries into empirical research and building narratives to make sense of possible futures and to broaden our view of scientific inquiry, and ( e) helping scholars grapple with the deep complexity of socioecological systems. As we explore these themes, we explain foundational qualitative approaches and highlight examples of environmental qualitative research that apply them.Expected final online publication date for the Annual Review of Environment and Resources, Volume 48 is October 2023. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Land degradation continues to be an enormous challenge to human societies, reducing food security, emitting greenhouse gases and aerosols, driving the loss of biodiversity, polluting water, and undermining a wide range of ecosystem services beyond food supply and water and climate regulation. Climate change will exacerbate several degradation processes. Investment in diverse restoration efforts, including sustainable agricultural and forest land management, as well as land set aside for conservation wherever possible, will generate co-benefits for climate change mitigation and adaptation and morebroadly for human and societal well-being and the economy. This review highlights the magnitude of the degradation problem and some of the key challenges for ecological restoration. There are biophysical as well as societal limits to restoration. Better integrating policies to jointly address poverty, land degradation, and greenhouse gas emissions and removals is fundamental to reducing many existing barriers and contributing to climate-resilient sustainable development.

Corporations are perceived as increasingly powerful and critically important to ensuring that irreversible climatological or ecological tipping points on Earth are not crossed. Environmental impacts of corporate activities include pollution of soils, freshwater and the ocean, depletion of ecosystems and species, unsustainable use of resources, changes to air quality, and alteration of the global climate. Negative social impacts include unacceptable working conditions, erosion of traditional practices, and increased inequalities. Multiple formal and informal mechanisms have been developed, and innovative examples of corporate biosphere stewardship have resulted in progress. However, the biosphere crisis underscores that such efforts have been insufficient and that transformative change is urgently needed. We provide suggestions for aligning corporate activities with the biosphere and argue that such corporate biosphere stewardship requires more ambitious approaches taken by corporations, combined with new and formalized public governance approaches by governments.

Automation carries paradigm-shifting potential for urban transport and has critical sustainability dimensions for the future of our cities. This article examines the diverse environmental and energy-related dimensions of automated mobility at the city level by reviewing an emerging and increasingly diversified volume of literature for road, rail, water, and air passenger transport. The multimodal nature of this investigation provides the opportunity for a novel contribution that adds value to the literature in four distinctive ways. It reviews from a sustainability angle the state of the art underpinning the transition to a paradigm of automated mobility, identifies current knowledge gaps highlighting the scarcity of non-technicalresearch outside the autonomous car's realm, articulates future directions for research and policy development, and proposes a conceptual model that contextualizes the automation-connectivity-electrification-sharing-multimodality nexus as the only way forward for vehicle automation to reach its pro-environmental and resource-saving potential.

A series of international initiatives have set ambitious goals for restoring global forests. This review synthesizes natural and social science research on forest restoration (FR), with a focus on restoration on cleared land in low- and middle-income countries. We define restoration more broadly than reestablishing native forests, given that landholders might prefer other forest types. We organize the review loosely around ideas in the forest transition literature. We begin by examining recent trends in FR and forest transition indicators. We then investigate two primary parts of the forest transition explanation for forest recovery: wood scarcity, including its connection to restoration for climate change mitigation, and the dynamic relationships between migration and land use. Next, we review ecological and silvicultural aspects of restoration on cleared land. We conclude by discussing selected interventions to promote restoration and the challenge of scaling up restoration to achieve international initiatives' goals.

Great claims have been made about the benefits of dematerialization in a digital service economy. However, digitalization has historically increased environmental impacts at local and planetary scales, affecting labor markets, resource use, governance, and power relationships. Here we study the past, present, and future of digitalization through the lens of three interdependent elements of the Anthropocene: ( a) planetary boundaries and stability, ( b) equity within and between countries, and ( c) human agency and governance, mediated via ( i) increasing resource efficiency, ( ii) accelerating consumption and scale effects, ( iii) expanding political and economic control, and ( iv) deteriorating social cohesion. While direct environmental impacts matter, the indirect and systemic effects of digitalization are more profoundly reshaping the relationship between humans, technosphere and planet. We develop three scenarios: planetary instability, green but inhumane, and deliberate for the good. We conclude with identifying leverage points that shift human–digital–Earth interactions toward sustainability.

Biodiversity, a term now widely employed in science, policy, and wider society, has a burgeoning associated literature. We synthesize aspects of this literature, focusing on several key concepts, debates, patterns, trends, and drivers. We review the history of the term and the multiple dimensions and values of biodiversity, and we explore what is known and not known about global patterns of biodiversity. We then review changes in biodiversity from early human times to the modern era, examining rates of extinction and direct drivers of biodiversity change and also highlighting some less-well-studied drivers. Finally, we turn attention to the indirect drivers of global biodiversity loss, notably humanity's increasing global consumption footprint, and explore what might be required to reverse the ongoing decline in the fabric of life on Earth.

Environmental factors, particularly those related to climate change, are stranding or could strand assets across different sectors and geographies with significant implications for economies, companies, financial institutions, communities, and workers. In this review, we focus on physical climate change, biodiversity loss, and litigation related to environmental factors as causes of stranded assets. We also review the emerging literature on the consequences of asset stranding for society before turning to some of the key supervisory responses that are emerging to ensure that stranded assets are measured and managed, particularly by financial institutions. These are among the areas of the stranded assets literature that have been growing most rapidly since 2015, and we focus on the literature produced since then.

This review explains the science behind the drive for global net zero emissions and why this is needed to halt the ongoing rise in global temperatures. We document how the concept of net zero carbon dioxide (CO2) emissions emerged from an earlier focus on stabilization of atmospheric greenhouse gas concentrations. Using simple conceptual models of the coupled climate–carbon cycle system, we explain why approximately net zero CO2 emissions and declining net energy imbalance due to other climate drivers are required to halt global warming on multidecadal timescales, introducing important concepts, including the rate of adjustment to constant forcing and the rate of adjustment to zero emissions. The concept of net zero was taken up through the 5th Assessment Report of the Intergovernmental Panel on Climate Change and the United Nations Framework Convention on Climate Change (UNFCCC) Structured Expert Dialogue, culminating in Article 4of the 2015 Paris Agreement. Increasing numbers of net zero targets have since been adopted by countries, cities, corporations, and investors. The degree to which any entity can claim to have achieved net zero while continuing to rely on distinct removals to compensate for ongoing emissions is at the heart of current debates over carbon markets and offsetting both inside and outside the UNFCCC. We argue that what matters here is not the precise makeup of a basket of emissions and removals at any given point in time, but the sustainability of a net zero strategy as a whole and its implications for global temperature over multidecadal timescales. Durable, climate-neutral net zero strategies require like-for-like balancing of anthropogenic greenhouse gas sources and sinks in terms of both origin (biogenic versus geological) and gas lifetime.

The knowledge, values, and practices of Indigenous peoples and local communities offer ways to understand and better address social-environmental problems. The article reviews the state of the literature on this topic by focusing on six pathways by which Indigenous peoples and local communities engage with management of and relationships to nature. These are (a) undertaking territorial management practices and customary governance, (b) contributing to nature conservation and restoration efforts with regional to global implications, (c) co-constructing knowledge for assessments and monitoring, (d) countering the drivers of unsustainable resource use and resisting environmental injustices, (e) playing key roles in environmental governance across scales, and (f) offering alternative conceptualizations of the interrelations between people and nature. The review shows that through these pathways Indigenous peoples and local communities are making significant contributions to managing the health of local and regional ecosystems, to producing knowledge based in diverse values of nature, confronting societal pressures and environmental burdens, and leading and partnering in environmental governance. These contributions have local to global implications but have yet to be fully recognized in conservation and development polices, and by society at large.

Climate change worry, eco-anxiety, and ecological grief are concepts that have emerged in the media, public discourse, and research in recent years. However, there is not much literature examining and summarizing the ways in which these emotions are expressed, to what processes they are related, and how they are distributed. This narrative review aims to (a) summarize research about the relationships between, on the one hand, negative emotions in relation to climate change and other environmental problems and, on the other hand, mental well-being among people in different parts of the world and (b) examine studies that have explored the potentially constructive role of worry—for example, in the form of providing motivation to act. It is clear from this review that negative emotions regarding environmental problems are normal, and often constructive, responses.Yet, given the nature, range, and extent of these emotions, it is important to identify diverse place-based and culturally relevant strategies to help people cope.

This article undertakes a comprehensive review of tourism's impacts on social-ecological systems and the use of the local to global commons. It examines a wide range of issues from climate change and air travel to biodiversity loss, pollution, and overtourism. It reinforces that tourism in modernity has pursued a dominant growth-driven paradigm of development and market expansion that is unsustainable. The review raises critical questions about how to move forward in the Anthropocene, where climate change is an existential threat to which travel and tourism must adjust. We offer directions for knowledge creation to develop nature-positive tourism that decouples from greenhouse gas emissions and seeks the regeneration of natural capital and communal health and well-being. This direction includes rethinking the purposes and values of tourism by addressing equity and ethical issues. It also calls for inclusivity of diverse worldviews and knowledge systems, including traditional and Indigenous knowledge. Such a pluralistic paradigm replaces the unsustainable modernist tourism paradigm that has dominated its evolution. We conclude with suggestions for research to advance nature-positive tourism.

Understanding why people do what they do is central to advancing equitable and sustainable futures. Yet, theories about human action are fragmented across many social science disciplines, each with its own jargon and implicit assumptions. This fragmentation has hindered theory integration and accessibility of theories relevant to a given challenge. We synthesized human action theories from across the humanities and social sciences. We developed eight underlying assumptions—metatheories—that reveal a fundamental organization of human action theories. We describe each metatheory and the challenges that it best elucidates (illustrated with climate change examples). No single metatheory addresses the full range of factors and problems; only one treats interactions between factors. Our synthesis will help researchers, policymakers, and practitioners gain a multifaceted understanding of human action.

Cooling is fundamental to quality of life in a warming world, but its growth trajectory is leading to a substantial increase in energy use and greenhouse gas emissions. The world is currently locked into vapor-compression air conditioning as the aspirational means of staying cool, yet billions of people cannot access or afford this technology. Non–vapor compression technologies exist but have low Technological Readiness Levels. Important alternatives are passive cooling measures that reduce mechanical cooling requirements and often have long histories of local use. Equally, behavioral and cultural approaches to cooling play a vital role. Although policies for a circular economy for cooling, such as production and waste, recovery of refrigerants, and disposal of appliances, are in development, more efforts are needed across the cooling life cycle. This article discusses the knowledge base for sustainable cooling in the built environment and its significant, interconnected, and coordinated technical, social, economic, and policy approaches.