Clean air matters to everyone. But the sources, impacts and solutions to air pollution can vary widely depending on where you live, work and travel. This Clean Air Day, research from the National Centre for Atmospheric Science (NCAS) highlights how understanding air quality across different settings – from homes and city streets to ports and airports – can help protect people’s health and support better decisions for communities across the UK and beyond.

Air pollution can affect people’s health across their lifespan. NCAS research has shown that even short-term exposure can make a difference. In one study, just a single hour of exposure to everyday levels of air pollution was found to affect both lung function and brain activity, underlining how closely air quality is tied to daily wellbeing.

Scientists are also working to better explain the “invisible threat” of air pollution. Many harmful pollutants can’t be seen, but they can penetrate deep into the lungs and enter the bloodstream, increasing the risk of respiratory illness, cardiovascular disease and other health problems. Learn more about the impacts of air pollution on human health.

NCAS researchers have contributed to major national reports, including work with the Royal College of Physicians, helping to build the scientific evidence that connects air pollution directly to public health outcomes.

Air pollution does not affect everyone equally. NCAS research has highlighted clear disparities in exposure across the UK, with minoritised ethnic groups often facing higher levels of pollution. This reflects patterns in housing, infrastructure and urban development.

Studies in Bradford, for example, revealed high levels of indoor air pollution in family homes, showing that air quality challenges are not limited to outdoor environments. Together, these findings emphasise the need for solutions that consider people’s lived experiences and ensure that improvements in air quality benefit all communities.

Air pollution sources differ depending on location, and NCAS research is helping to map these differences in detail.

In cities like London, the sources of pollution are changing. As vehicle emissions have decreased, other sources have become more important. Gas boilers are now a leading contributor to urban air pollution, while construction activity has emerged as a significant source of black carbon. These shifts highlight the importance of continuously updating our understanding of urban pollution.

At the same time, cutting-edge monitoring techniques are improving how scientists track vehicle exhaust emissions in real time, offering new ways to identify hotspots and support targeted action in busy urban areas.

Transport hubs also play a crucial role. Research around UK airports has shown that air pollution linked to aviation can affect nearby communities, raising important questions about how to balance economic activity with local health impacts.

NCAS scientists are also investigating air quality in busy ports, such as Southampton, because emissions from vessels – particularly when cruise ships are docked – can be transported into residential areas.

Alongside identifying problems, NCAS research is exploring solutions to reduce emissions across different sectors.

In aviation, scientists are investigating how sustainable aviation fuels influence both air quality and climate. In construction, low-emission hydrogen engines are being studied as a potential way to cut pollution from heavy machinery.

Meanwhile, regulations on paints and solvents have already led to significant reductions in harmful emissions, although further policy updates are needed to keep pace with scientific understanding.

NCAS scientists have also confirmed a major global reduction in ship sulfur emissions following international regulations, demonstrating how coordinated policy action can deliver measurable improvements in air quality.

These examples show how science can inform innovation, helping industries transition to cleaner technologies or products.

Air pollution is not confined by national borders. NCAS research in East Asia has explored how air pollution interacts with climate change, demonstrating that the same emissions can influence both local air quality and global warming. Understanding these links is essential for developing strategies that deliver benefits for both health and climate.

Across all of this work, a common theme emerges: air quality is shaped by the connection between people, places and activities. From the air inside our homes to emissions from global shipping, every source contributes to a bigger picture.

By combining detailed measurements, innovative technologies and community-focused research, NCAS is building a clearer understanding of how air pollution affects people – and how it can be reduced. This evidence is crucial for policymakers, city planners and communities working to create cleaner, healthier environments.

On Clean Air Day, the message is simple: improving air quality starts with understanding it. And through its research, NCAS is helping turn that understanding into action that benefits people across the UK and beyond.