Every US$1 invested in tackling climate change and air pollution together could generate around US$15 in economic benefits, according to a new report by the UN Environment Programme (UNEP) and the Climate and Clean Air Coalition (CCAC).
The assessment, published on the International Day of Clean Air for blue skies, is the first comprehensive global economic analysis of integrated climate and clean-air action.
It found that tackling the two problems together delivers greater economic returns than addressing them separately, with benefits ranging from lower healthcare costs and higher productivity to reduced climate-related damage and fewer premature deaths.
“For too long, we have treated climate action as a cost to be managed and air pollution as the unfortunate outcome of development,” said Inger Andersen, executive director of UNEP.
“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.”
The report estimates that implementing a package of 25 measures could generate annual economic benefits equivalent to 2.8 per cent of global GDP by 2035, 4.5 per cent by 2050 and 11.4 per cent by 2100.
By contrast, explicit 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.
The report warns that every year of delayed action would mean forfeiting more than US$1.5 trillion in annual economic benefits, equivalent to about 0.5 per cent of global GDP.
Even when non-market welfare benefits are excluded, the measures would generate around US$4 for every US$1 invested.
Millions of deaths linked to air pollution
The estimated US$15 return includes market benefits such as lower healthcare expenditure, increased labour productivity and avoided physical damage, as well as the economic value of preventing premature deaths and improving quality of life.
In 2025, exposure to human-caused outdoor air pollution, including fine particulate matter (PM2.5) and ozone, was linked to an estimated 6.4 million premature deaths worldwide, according to the report.
Household air pollution was associated with a further two 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 two million new cases of dementia in 2025, alongside millions of cases of heart attacks, pulmonary disease, diabetes, strokes and lung cancer.
25 measures across six sectors
The package examined by the report covers energy and fossil-fuel systems, industry, transport, agriculture and food, residential cooking and heating, and waste management.
It combines long-term decarbonisation measures with policies aimed at reducing so-called super-pollutants, including methane, black carbon and hydrofluorocarbons (HFCs).
Measures include expanding renewable energy and improving energy efficiency, cleaner cooking and heating, tougher vehicle emissions standards, electric vehicles, low-sulphur shipping fuels and measures to reduce oil and gas leaks, venting and flaring.
The package also includes improved livestock and manure management, more efficient fertiliser use, improved rice cultivation, alternatives to crop-residue burning, better solid-waste and wastewater management, and the phase-down of HFCs.
Full implementation could prevent 144 million air-pollution-related premature deaths by 2050, including 96 million deaths linked to outdoor air pollution, while also preventing hundreds of millions of cases of chronic disease.
Climate benefits
The measures could also substantially reduce greenhouse-gas emissions.
Compared with the report’s baseline scenario, immediate implementation would halve global carbon dioxide emissions by 2050, cut methane emissions by 60 per cent and reduce major air pollutants, including black carbon, sulphur dioxide and nitrogen oxides, by about 70 per cent.
The measures could avoid approximately 0.34°C of global warming by 2050 and 1.4°C by 2100.
Because land temperatures are rising faster than the global average, the reduction in warming could reach an estimated 1.5°C to 2°C in many regions by the end of the century.
By 2100, carbon dioxide emissions under the scenario would be net negative, while major air pollutants could fall by as much as 85 per cent.
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 as separate issues underestimated the potential benefits of action.
“When we modelled them together, the returns were larger than each could show alone, because the same sources, sectors and policies so often drive both,” he said.
The report said the economic benefits of cleaner air could materialise quickly enough to outweigh implementation costs within a decade. Cleaner air would continue to account for almost half of the total economic benefits by 2100.
Governments urged to close implementation gap
The report identifies fragmented decision-making, limited enforcement capacity and weak co-ordination between government agencies as major barriers to implementation.
Together, these institutional obstacles could delay full implementation of the measures by almost eight years globally.
The report says fiscal incentives and regulations that encourage the private sector to deploy profitable emissions-reduction technologies could accelerate implementation and unlock up to US$10 trillion in additional health benefits by 2040.
It calls for governments to integrate climate, air-quality, health and economic planning, strengthen institutions and enforcement, and better align public and private finance.
Elliott Harris, an independent co-chair of the assessment, said the estimated 15-to-one benefit-cost ratio should make integrated climate and clean-air action attractive to investors.
“The only reason it hasn’t on integrated climate and clean air action yet is that the returns are split across health systems, productivity and avoided climate damage rather than landing on a single balance sheet,” he said.
The report argues that bringing climate and air-quality policies together could therefore deliver significant economic, health and environmental gains while helping governments accelerate the transition to cleaner energy and lower-emission economies.