Tropospheric ozone is one of the super pollutants, including methane, that combined are driving 45% of global warming. On its own, tropospheric ozone is causing approximately 0.25°C of present-day warming. The damage it causes goes beyond climate change – it also contributes massively to air pollution, damages crops and seriously affects people’s health.

Tropospheric ozone is formed when sunlight interacts with a suite of pollutants, where nitrogen oxides  and volatile organic compounds  like methane are the main drivers. These are largely emitted from transport, industry including oil and gas production, livestock and energy generation.

Tropospheric ozone causes huge damage in the areas where it is formed but can also travel significant distances, even reaching neighbouring countries, affecting people and communities far from where it was originally produced. It disproportionately affects people in the Global South, causing globally almost 500,000 premature deaths every year, up to 26% reduction of global crop yield of crops like wheat and soybeans, and is responsible for a decrease of up to 11% in carbon captured by forests globally.

We need to act now, and we need a joined-up approach at a global, regional and national level. We already have proven approaches that reduce the impact of tropospheric ozone and deliver cleaner air, improve health and reduce global warming. We can make a bigger impact if more governments developed action plans that urgently address the specific challenges of tropospheric ozone, as this issue is not significantly included in current climate change and air quality policies at global, national, or local levels.

We have formed Action on Tropospheric Ozone to make the case for action on tackling this damaging pollutant. We are producing a policy brief that will explain why governments and institutions need to take action now, showcasing critical success stories that demonstrate that reducing tropospheric ozone is possible and brings enormous benefits that help combat climate change, protect our ecosystem and improve people’s health globally.