Treating air pollution and climate change as one problem pays better than handling them separately, according to a new UN-backed assessment. The report estimates roughly $15 in economic benefits for every $1 spent.
The numbers behind the case
The study, titled "Hidden assets: The economic and health case for climate and clean air action," was produced by the UN Environment Programme and the Climate and Clean Air Coalition. It sets out 25 proven measures, including renewable power, energy efficiency, clean cooking and heating, stronger vehicle emission standards, electric vehicles, low-sulfur shipping fuels, reduced oil and gas leaks and better livestock and fertiliser management.
The report estimates annual benefits equal to 2.8 percent of global GDP in 2035, 4.5 percent in 2050 and 11.4 percent in 2100. Even when welfare gains such as longer and healthier lives are excluded, the measures still return about $4 per dollar invested. For comparison, explicit fossil fuel subsidies accounted for 2.18 percent of global GDP in 2022.
"A benefit-cost ratio of 15 to 1 would attract capital instantly in almost any other sector," said Elliott Harris, independent co-chair of the assessment. "Every year of delay costs the world more than $1.5 trillion in benefits we will not get back."
Health costs already being paid
The report puts numbers on the damage. In 2025, exposure to human-caused outdoor air pollution, including fine particulate matter and ozone, was linked to 6.4 million premature deaths worldwide. Household air pollution was linked to a further two million deaths, including about 300,000 children.
Outdoor air pollution also contributed to 5.5 million new cases of childhood asthma and two million new cases of dementia last year, along with heart attacks, lung disease, diabetes, stroke and lung cancer. Full implementation of the 25 measures could prevent 144 million air pollution related premature deaths by 2050, the report says.
Climate gains would come with the health gains. Compared with the baseline scenario, immediate action would halve global carbon dioxide emissions by 2050, cut methane by 60 percent and reduce major air pollutants by about 70 percent. It would avoid about 0.34 degrees Celsius of warming by 2050 and 1.4 degrees by 2100.
Barriers, not science
"For too long, we have treated climate action as a cost to be managed and air pollution as the unfortunate outcome of development," said UNEP Executive Director Inger Andersen. "This report shows the opposite."
UN Secretary-General Antonio Guterres said accelerating the move away from fossil fuels is one of the fastest ways to clean the air while tackling the climate crisis. The report identifies fragmented decision-making, limited enforcement capacity and weak coordination between governments as the main barriers, and calls for integrated planning on climate, air quality, health and economics.