Investing simultaneously in climate action and cleaner air could deliver one of the strongest economic returns available to governments and investors, with every US$1 spent generating around US$15 in economic benefits, according to a new United Nations Environment Programme assessment.
The findings of UNEP’s Hidden Assets climate and clean-air report strengthen the economic case for treating air pollution reduction, decarbonisation and public health as interconnected investment priorities rather than separate policy programmes.
The UNEP and Climate and Clean Air Coalition (CCAC) report, Hidden Assets: The Economic and Health Case for Climate and Clean Air Action, assesses 25 measures across six major economic sectors. UNEP describes it as the most comprehensive assessment yet of the costs and benefits of integrated climate and clean-air policies.
The headline 15-to-1 benefit-cost ratio includes both direct economic gains and the monetary value associated with improved health, fewer premature deaths and better quality of life. Even when non-market welfare benefits are excluded, the measures are estimated to generate approximately US$4 for every US$1 invested.
Climate Action Could Generate Benefits Worth 4.5% of Global GDP by 2050
The economic impact increases substantially as the measures scale.
UNEP estimates that annual economic benefits from implementing the 25 measures would be equivalent to 2.8 percent of global GDP in 2035, rising to 4.5 percent in 2050 and 11.4 percent by 2100.
Those figures put the potential economic value of climate and air-quality measures into perspective. Explicit fossil-fuel subsidies represented 2.18 percent of global GDP in 2022, while global healthcare expenditure accounted for 9.3 percent of GDP in 2023, according to figures cited in the assessment.
Delaying implementation also carries a substantial opportunity cost. UNEP estimates that every year of delay would forgo more than US$1.5 trillion annually, equivalent to approximately 0.5 percent of global GDP, in combined market and non-market benefits.
The report estimates an internal rate of return of about 60 percent, while direct market returns could exceed implementation costs within 10 years.
Air Pollution Linked to 6.4 Million Premature Deaths
A major portion of the economic return comes from improving public health.
In 2025, exposure to human-caused outdoor air pollution, particularly PM2.5 and ozone, was associated with an estimated 6.4 million premature deaths worldwide.
Household air pollution was associated with another 2 million premature deaths, including approximately 300,000 children.
The health burden extends well beyond mortality. Outdoor air pollution contributed to an estimated 5.5 million new childhood asthma cases and 2 million new dementia cases in 2025, alongside millions of cases involving heart attacks, pulmonary disease, diabetes, strokes and lung cancer.
These illnesses carry substantial economic costs through healthcare expenditure, lost working days, lower labour productivity and reduced well-being.
That explains why cleaner air represents such a large component of the investment case. UNEP says its economic value can materialise quickly enough to outweigh implementation costs within a decade and could still represent almost half of the overall economic benefits in 2100.
25 Climate and Clean-Air Measures Could Prevent 144 Million Deaths
The assessment identifies 25 proven measures covering six sectors: energy and fossil-fuel systems, industry, transport, agriculture and food systems, residential cooking and heating, and waste management.
The measures include expanding renewable electricity and energy efficiency, adopting cleaner cooking and heating systems, strengthening vehicle emissions standards, accelerating electric vehicles and introducing low-sulphur shipping fuels.
Other measures focus on cutting methane leakage and routine oil and gas flaring, improving livestock and manure management, using fertilisers more efficiently, changing rice cultivation practices, eliminating crop-residue burning, improving solid-waste and wastewater management and phasing down hydrofluorocarbons.
If fully implemented, UNEP estimates the package could cumulatively prevent 144 million air-pollution-related premature deaths by 2050.
Of these, approximately 96 million deaths would be prevented through reductions in ambient air pollution alone. Hundreds of millions of chronic-disease cases could also be avoided.
CO2 Emissions Could Be Halved by 2050
The same investments would produce significant climate benefits.
Compared with the report’s baseline scenario, immediate implementation of the 25 measures could halve global carbon dioxide emissions by 2050.
Methane emissions could decline by approximately 60 percent, while major air pollutants including black carbon, sulphur dioxide and nitrogen oxides could fall by around 70 percent.
The measures could avoid approximately 0.34°C of global warming by 2050 and as much as 1.4°C by 2100.
Because temperatures over land typically increase faster than the global average, avoided warming across many regions could reach approximately 1.5°C to 2°C by 2100.
By the end of the century, CO2 emissions under the assessment’s scenario would become net negative, while major air pollutants could fall by as much as 85 percent.
The findings are particularly significant as a separate 2026 UNEP assessment warns that global temperatures are now expected to exceed 1.5°C, with its most optimistic scenario putting peak warming at around 1.8°C above pre-industrial levels.
Eight-Year Implementation Gap Threatens Economic Benefits
Technology and economics may not be the biggest obstacles.
UNEP identifies fragmented decision-making, weak enforcement capacity and insufficient coordination between government institutions as major barriers to implementation.
Together, these institutional constraints could delay full implementation by almost eight years globally.
Closing that implementation gap through stronger regulation, fiscal incentives and policies that encourage private companies to deploy profitable low-emission technologies could unlock as much as US$10 trillion in additional health benefits by 2040.
That puts finance ministries, development banks and institutional investors at the centre of the transition. The challenge is that the economic returns are distributed across healthcare systems, workforce productivity, energy security and avoided climate damage rather than appearing as revenue on a single corporate balance sheet.
Clean Air Emerges as an Economic Asset
The UNEP assessment changes the traditional framing of climate spending from an environmental cost toward an economic investment.
A US$15 economic benefit for every US$1 invested, a roughly 60 percent internal rate of return, potential prevention of 144 million premature deaths by 2050, and benefits equivalent to 4.5 percent of global GDP by mid-century create a substantial economic argument for faster deployment.
The investment opportunity also extends across multiple industries. Renewable energy developers, electric-vehicle manufacturers, clean-cooking companies, methane-monitoring technology providers, waste-management companies, industrial efficiency suppliers and emissions-control technology companies could all benefit from stronger implementation.
The central message from the assessment is therefore not simply that climate and air-pollution policies produce environmental benefits. Integrated action can generate measurable economic returns while simultaneously cutting healthcare costs, improving productivity, reducing emissions and avoiding climate damage.
With more than US$1.5 trillion in potential benefits lost for every year of delay, accelerating climate and clean-air investment increasingly looks like an economic competitiveness and public-health strategy as much as an environmental one.
BABURAJAN KIZHAKEDATH
