Policy Brief

Global household material use is highly unequal: the top 10% drive roughly a third of footprints and most of the overshoot beyond safe limits. Curbing affluent overconsumption, while securing decent material floors, should be a central policy lever to cut material demand quickly and fairly.

River protection in the United States remains scant, with just over one-tenth of river length in the contiguous states protected at viable levels, often by land-based protection measures that fail to capture the full diversity of the nation’s river systems. There is an urgent need for policies that safeguard, strengthen and expand freshwater protections to secure rivers that sustain both people and nature.

Governments worldwide collected US$923 billion in fuel taxes in 2023, revenues at risk with the transition to electric vehicles, especially in lower-income countries. Policymakers should anticipate and assess their own domestic exposure and develop policies to recover enough revenues from electric vehicles as the transition progresses.

Thermal power generation faces risks from rising water temperatures and scarcity, worsened by decarbonization efforts that prioritize the retirement of lower-risk units. To reconcile energy security and climate goals, policymakers should factor hydroclimatic risks into power plant retirement and energy transition planning.

An ensemble of green industrial policies and targeted subsidies, coupled with a mild carbon tax, is the most promising strategy to support an orderly transition towards achieving the Paris Agreement targets. Such a policy package can be designed to have a neutral effect on public finances and boost job creation, while preserving economic stability and income growth.

Global climate mitigation and clean cooking fuel use improves air quality and cardiopulmonary health for the majority of the world’s population. Co-implementation of strategies addressing both outdoor and household air pollution offers greater and sustained long-term health benefits.

Major greenhouse gas emissions from chemicals and plastics are overlooked under the current design of the European Union’s Carbon Border Adjustment Mechanism. To close these important gaps in coverage, policymakers should include fossil-based feedstocks and raise country-specific default emissions values to ensure fair and comprehensive carbon accounting.

Investing in waste management infrastructure in the global south nets a more cost-efficient sustainability return when compared with advancing technology improvements in the global north. Efforts to reduce ocean plastic and to mitigate the climate change footprint of discarded municipal waste should include strategies to bring basic collection and disposal practices to those regions where they are lacking.

Assessing linkages between irrigation expansion and child diet diversity in the global south revealed larger diet diversity improvements in water-stressed regions. Future irrigation planning should explicitly incorporate nutrition-sensitive strategies to ensure food security of local communities while maintaining sustainable water withdrawals.

Transformation to healthier and more sustainable diets in China can generate measurable benefits for nutrition, the environment and food affordability. Integrating multidimensional sustainability goals into China’s dietary guidelines can help to align food policy with long-term societal and environmental improvements.

Evaluating the short-term exposure to wildfire-specific fine particulate matter (PM_2.5) showed greater risks of hospitalization for all major respiratory diseases than non-wildfire PM_2.5. When developing air quality guidelines, it is also important to consider that PM_2.5 from varying sources can have different health effects, which require targeted health and environmental policy approaches.

The co-accumulation and close interactions of climate-friendly organic carbon and neurotoxic mercury in coastal ecosystems show that nature-based solutions to the climate crisis can alter the global mercury cycle and risk. Nature-based mitigation and adaptation strategies should therefore consider the carbon–mercury nexus to maximize sustainability goals.