UN: Every US$1 invested in climate and clean-air action can return US$15
Investing in measures that tackle climate change and air pollution together could generate about US$15 in economic benefits for every US$1 invested, according to a new global assessment by the United Nations Environment Programme (UNEP) and the Climate and Clean Air Coalition (CCAC).
The finding is contained in Hidden Assets: The Economic and Health Case for Climate and Clean Air Action, released on the International Day of Clean Air for Blue Skies. The report is described as the first comprehensive global economic assessment of integrated climate and clean-air action.
The US$15 return includes both market and non-market benefits, ranging from reduced healthcare costs and higher labour productivity to avoided climate-related damage and the economic value of preventing premature deaths and improving health.
“For too long, we have treated climate action as a cost to be managed and air pollution as the unfortunate outcome of development,” UNEP Executive Director Inger Andersen said. “This report shows the opposite: clean air is a key driver of development, health, food and energy security, and climate stability – an asset we must invest in.”
Trillions at stake
The assessment found that implementing 25 identified measures could generate annual economic benefits equivalent to 2.8 per cent of global GDP by 2035, rising to 4.5 per cent by 2050 and 11.4 per cent by 2100.
The economic opportunity comes against substantial existing expenditure. The report notes that fossil fuel subsidies accounted for 2.18 per cent of global GDP in 2022, while healthcare spending represented 9.3 per cent of global GDP in 2023.
Delaying action also carries a significant economic cost. Each year of delay could result in more than US$1.5 trillion in forgone benefits, equivalent to about 0.5 per cent of global GDP annually.
Even when non-market welfare benefits are excluded, the measures are estimated to generate about US$4 for every US$1 invested.
Elliott Harris, an independent co-chair of the assessment, said the high returns were being overlooked because the benefits of climate and clean-air policies are distributed across different parts of the economy.
“The returns are split across health systems, productivity and avoided climate damage rather than landing on a single balance sheet,” Harris said.
Air pollution’s human toll
The economic case is closely linked to the health burden caused by polluted air.
In 2025, exposure to human-caused outdoor air pollution, particularly fine particulate matter (PM2.5) and ozone, was associated with an estimated 6.4 million premature deaths globally, while household air pollution contributed another 2 million premature deaths, including about 300,000 children.
The report also estimates that outdoor air pollution contributed to 5.5 million new cases of childhood asthma and 2 million new cases of dementia in 2025, alongside millions of cases of heart attack, pulmonary disease, diabetes, stroke and lung cancer.
By incorporating healthcare costs, lost productivity and impacts on wellbeing, the assessment places a wider economic value on reducing these health effects.
25 measures across key sectors
The proposed package covers six major areas: energy and fossil fuel systems, industry, transport, agriculture and food systems, residential cooking and heating, and waste management.
Measures include expanding renewable energy and energy efficiency, improving access to clean cooking and heating, strengthening vehicle emission and efficiency standards, promoting electric vehicles and using low-sulfur fuels in shipping.
The package also targets methane and other short-lived climate pollutants through measures such as reducing oil and gas leaks, ending routine venting and flaring, improving livestock and manure management, using fertiliser more efficiently, improving rice cultivation and reducing crop-residue burning.
Better solid waste and wastewater management, together with the phase-down of hydrofluorocarbons, are also included.
Climate benefits
The measures could deliver substantial climate and air-quality improvements if implemented immediately.
Compared with the report’s baseline scenario, full implementation could halve global carbon dioxide emissions by 2050, reduce methane emissions by 60 per cent and cut major air pollutants, including black carbon, sulphur dioxide and nitrogen oxides, by about 70 per cent.
The measures could also avoid approximately 0.34°C of global warming by 2050 and 1.4°C by 2100. In many regions, avoided warming could reach 1.5–2°C by the end of the century because land areas generally warm faster than the global average.
By 2050, the measures could cumulatively prevent an estimated 144 million air-pollution-related premature deaths, including 96 million linked specifically to ambient air pollution, as well as hundreds of millions of chronic disease cases.
Closing the implementation gap
Despite the potential gains, fragmented decision-making, limited enforcement capacity and weak coordination between government institutions remain major obstacles.
The report estimates that these barriers could delay full implementation globally by almost eight years. Addressing them through stronger regulation, fiscal incentives and improved government coordination could accelerate the deployment of profitable emissions-reduction technologies and unlock up to US$10 trillion in additional health benefits by 2040.
Simon Dietz, co-chair of the assessment and Professor of Environmental Policy at the London School of Economics, said treating climate change and air pollution separately risks understating the benefits of action because many of their sources and solutions overlap.
The report therefore calls for climate, air-quality, health and economic policies to be planned together, with stronger institutions, enforcement and closer alignment between public and private finance.