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The COVID-19 pandemic and Russia’s war on Ukraine have impacted the global economy, including the energy sector. The pandemic caused drastic fluctuations in energy demand, oil price shocks, disruptions in energy supply chains, and hampered energy investments, while the war left the world with energy price hikes and energy security challenges. The long-term impacts of these crises on low-carbon energy transitions and mitigation of climate change are still uncertain but are slowly emerging. This paper analyzes the impacts throughout the energy system, including upstream fuel supply, renewable energy investments, demand for energy services, and implications for energy equity, by reviewing recent studies and consulting experts in the field. We find that both crises initially appeared as opportunities for low-carbon energy transitions: the pandemic by showing the extent of lifestyle and behavioral change in a short period and the role of science-based policy advice, and the war by highlighting the need for greater energy diversification and reliance on local, renewable energy sources. However, the early evidence suggests that policymaking worldwide is focused on short-term, seemingly quicker solutions, such as supporting the incumbent energy industry in the post-pandemic era to save the economy and looking for new fossil fuel supply routes for enhancing energy security following the war. As such, the fossil fuel industry may emerge even stronger after these energy crises creating new lock-ins. This implies that the public sentiment against dependency on fossil fuels may end as a lost opportunity to translate into actions toward climate-friendly energy transitions, without ambitious plans for phasing out such fuels altogether. We propose policy recommendations to overcome these challenges toward achieving resilient and sustainable energy systems, mostly driven by energy services.

Many households worldwide face substantial gaps in decent living standards (DLS), universal and essential material preconditions for achieving well-being and inclusive development. Here, we use subnational Demographic and Health Survey data from 75 low and middle-income countries (1990–2021) to explore the distribution and trends of ten living standards. We estimate that 94.9% of households in our dataset lack the material prerequisites for at least one of the ten standards, and 63.6% for one-third of them. Stark inequalities persist both within and between countries, with regions in sub-Saharan Africa experiencing the most severe deprivations. Despite some improvements, progress remains limited in critical areas such as health care, sanitation, housing, and education. Within countries, rural, agrarian households with low levels of educational attainment are particularly disadvantaged. These granular findings at the subnational level can help direct policy efforts and resources towards those populations most in need. Using subnational Demographic and Health Survey data from 75 low and middle-income countries, the authors show that many households lack access to decent living standards as basic prerequisites for human well-being. Major inequalities exist within and across countries and by socio-economic backgrounds.

Keeping the Earth system in a stable and resilient state, to safeguard Earth's life support systems while ensuring that Earth's benefits, risks, and related responsibilities are equitably shared, constitutes the grand challenge for human development in the Anthropocene. Here, we describe a framework that the recently formed Earth Commission will use to define and quantify target ranges for a “safe and just corridor” that meets these goals. Although “safe” and “just” Earth system targets are interrelated, we see safe as primarily referring to a stable Earth system and just targets as being associated with meeting human needs and reducing exposure to risks. To align safe and just dimensions, we propose to address the equity dimensions of each safe target for Earth system regulating systems and processes. The more stringent of the safe or just target ranges then defines the corridor. Identifying levers of social transformation aimed at meeting the safe and just targets and challenges associated with translating the corridor to actors at multiple scales present scope for future work. Plain Language Summary For the first time in human history, we are now forced to consider the real risk of destabilizing our home, planet Earth. This is an existential risk, as we all need a planet that can sustain life and provide the basis for the well‐being of all people. Here, we outline a conceptual framework for a global‐scale “safe and just corridor” that delivers on these goals for people and the planet. The recently formed Earth Commission will use this framework to map key functions that regulate the state of the Earth system and provide life support to us humans, including processes such as biodiversity and nutrient cycling. It will also analyze the related justice components, for each of these Earth system target domains, in terms of how such ranges can be defined and how nature's contributions to people can be justly shared. Furthermore, social transformations that meet safe and just targets for all people and how the global‐scale targets can be translated to targets for actors at other scales will be explored. Key Points An integrated people and planet perspective is required to guide human development and use of the global commons We outline an approach to defining a safe and just corridor for a stable and resilient planet supporting human development A conceptual framework for linking safe and just Earth system targets is proposed

With the Sustainable Development Goals (SDGs), the global community has set itself an ambitious development agenda. Current analytical and quantitative modeling capabilities fall short of being able to capture all 17 SDGs and their targets. Even highly ambitious and optimistic pathways currently used in research, such as SSP1/SSP1-2.6, do not meet all SDGs (sustainability gaps) and fail to provide information on some of them (knowledge gaps). We show that for research and modeling purposes, the SDG targets can serve as a basis but need to be operationalized to reduce complexity and also to account for long-term sustainability concerns beyond 2030. We have explored here the requirements for assessing more comprehensively the sustainability of development pathways, guided by holistic interpretation of the SDGs to enable an assessment of the potential embedded synergies and trade-offs between the economic, social and environmental objectives. We see this as call for action for science to work on filling these gaps. At the same time, this is also a call for policy makers and the global community to close the sustainability gaps that emerge from such analysis. We anticipate that such analysis will provide useful information for policy advice and investment decisions during implementation of the UN 2030 Agenda.

Positive tipping points are promising leverage points in social systems for accelerated progress towards climate and sustainability targets. Besides their impact in specific social systems such as energy, food, or social norms and values, positive tipping dynamics may in some cases spread across different systems, amplifying the impact of tipping interventions. However, the cross-system interactions that can create such tipping cascades are sparsely examined. Here, we review interactions across sociotechnical, socioecological, socioeconomic, and sociopolitical systems that can lead to tipping cascades based on the emerging and relevant past evidence. We show that there are several feedback mechanisms where a strategic input can trigger secondary impacts for a disproportionately large positive response, and various agents that can trigger such cascades. This review of cross-system interactions facilitates the quantification and analysis of positive tipping cascades in future studies.

Many scenarios for limiting global warming to 1.5°C assume planetary‐scale carbon dioxide removal sufficient to exceed anthropogenic emissions, resulting in radiative forcing falling and temperatures stabilizing. However, such removal technology may prove unfeasible for technical, environmental, political, or economic reasons, resulting in continuing greenhouse gas emissions from hard‐to‐mitigate sectors. This may lead to constant concentration scenarios, where net anthropogenic emissions remain non‐zero but small, and are roughly balanced by natural carbon sinks. Such a situation would keep atmospheric radiative forcing roughly constant. Fixed radiative forcing creates an equilibrium “committed” warming, captured in the concept of “equilibrium climate sensitivity.” This scenario is rarely analyzed as a potential extension to transient climate scenarios. Here, we aim to understand the planetary response to such fixed concentration commitments, with an emphasis on assessing the resulting likelihood of exceeding temperature thresholds that trigger climate tipping points. We explore transients followed by respective equilibrium committed warming initiated under low to high emission scenarios. We find that the likelihood of crossing the 1.5°C threshold and the 2.0°C threshold is 83% and 55%, respectively, if today's radiative forcing is maintained until achieving equilibrium global warming. Under the scenario that best matches current national commitments (RCP4.5), we estimate that in the transient stage, two tipping points will be crossed. If radiative forcing is then held fixed after the year 2100, a further six tipping point thresholds are crossed. Achieving a trajectory similar to RCP2.6 requires reaching net‐zero emissions rapidly, which would greatly reduce the likelihood of tipping events. Plain Language Summary The importance of reaching net‐zero greenhouse gas emissions to help avoid dangerous anthropogenic climate change is widely acknowledged. However, current national commitments do not align with this target and instead will lead to about 2.7°C warming by 2100. If the large‐scale carbon dioxide removal needed to reach net‐zero emissions is unfeasible and instead, the remaining hard‐to‐mitigate emissions approximately balance natural sinks, atmospheric greenhouse gas (GHG) concentrations will remain constant. Such fixed GHG levels will result in continued warming until the climate system reaches a state of radiative balance, which we call “committed warming.” We investigate the committed warming associated with the CO2 equivalent (CO2e) for each year for three emission scenarios. Critically, we then examine the probability of breaching tipping point thresholds at different levels of committed warming, finding that under the scenario that best matches current national commitments, we will be committed to crossing the critical temperature threshold for six key climate tipping points by 2100. Maintaining radiative forcing at only slightly elevated levels above present GHG concentrations will substantially alter parts of the Earth System through such “locked‐in” impacts. Society will only be able to avoid breaching tipping point thresholds through rapid and very substantial reduction of human emissions. Key Points We conduct a thought experiment on equilibrium global warming and tipping point likelihood under constant greenhouse gas concentration scenarios Maintaining radiative forcing at or above current levels would commit multiple parts of the climate system to passing tipping points Only a lower emissions scenario, which would require rapidly reaching net‐zero emissions, avoids crossing most climate tipping points

Collective climate action hinges on the distribution of benefits and burdens of climate change mitigation. Yet assumptions relevant to distributional justice are frequently made only implicitly in climate change mitigation scenarios. Here, we introduce the patterns of the distributional justice framework that operationalize philosophical justice theories as quantitative requirements for scenario trajectories. We then apply this framework to the IPCC AR6 scenario database to assess the distributional implications of global climate change mitigation scenarios across world regions. Focusing on scenario variables related to energy and meat consumption, we found a diversity of patterns of justice across scenario characteristics. The prioritarian perspective, which prioritizes improvements to those currently worse off, emerged as the most dominant pattern of justice. By contrast, futures with limited or reduced energy and meat consumption were the least represented in the database. Our research further indicates that most scenarios consistent with patterns of justice do not explicitly aim to model more just futures, suggesting that underlying scenario narratives—most often SSP2—largely determine the distributional outcomes. We therefore propose a stakeholder engagement strategy to make distributional justice assumptions in scenario development ex-ante more diverse and transparent. Overall, this study provides a practical avenue for developing justice-conscious scenarios that may be more likely to motivate collective climate action.

Increasing human demands for water, energy, food and materials, are expected to accentuate resource supply challenges over the coming decades. Experience suggests that long-term strategies for a single sector could yield both trade-offs and synergies for other sectors. Thus, long-term transition pathways for linked resource systems should be informed using nexus approaches. Global integrated assessment models can represent the synergies and trade-offs inherent in the exploitation of water, energy and land (WEL) resources, including the impacts of international trade and climate policies. In this study, we review the current state-of-the-science in global integrated assessment modeling with an emphasis on how models have incorporated integrated WEL solutions. A large-scale assessment of the relevant literature was performed using online databases and structured keyword search queries. The results point to the following main opportunities for future research and model development: (1) improving the temporal and spatial resolution of economic models for the energy and water sectors; (2) balancing energy and land requirements across sectors; (3) integrated representation of the role of distribution infrastructure in alleviating resource challenges; (4) modeling of solution impacts on downstream environmental quality; (5) improved representation of the implementation challenges stemming from regional financial and institutional capacity; (6) enabling dynamic multi-sectoral vulnerability and adaptation needs assessment; and (7) the development of fully-coupled assessment frameworks based on consistent, scalable, and regionally-transferable platforms. Improved database management and computational power are needed to address many of these modeling challenges at a global-scale.

Climate change and decarbonization raise complex justice questions that researchers and policymakers must address. The distributions of greenhouse gas emissions rights and mitigation efforts have dominated justice discourses within scenario research, an integrative element of the IPCC. However, the space of justice considerations is much larger. At present, there is no consistent approach to comprehensively incorporate and examine justice considerations. Here we propose a conceptual framework grounded in philosophical theory for this purpose. We apply this framework to climate mitigation scenarios literature as proof of concept, enabling a more holistic and multidimensional investigation of justice. We identify areas of future research, including new metrics of service provisioning essential for human well-being. Justice issues are integral to a variety of climate science and policy processes. This Perspective provides a framework, based on philosophical theory, to explain key justice concepts and how they can be applied in climate discussions.