Combining digital light painting and low-cost air pollution sensors, the team produced photographic evidence of pollution levels in cities across the three countries, illustrating:

• air pollution varying dramatically between locations in Ethiopia – a kitchen using biomass stoves for food preparation where particulate matter (PM_2.5) concentrations in the room were up to 20 times greater than what was measured nearby outdoors;
• two children’s playgrounds in India, 500km apart – one in urban Delhi, the other in rural Palampur – with PM_2.5 values at the Palampur playground at least 12.5 times less than those measured in Delhi; and
• large variations in air pollution around the Port Talbot steelworks, in Wales – air quality monitoring and light painting at dusk in summer measured PM_2.5 concentrations in the range of 30-40 mg/m³, when the hourly average value was 24 mg/m³. 

The journal Nature Communications Earth & Environment published the findings of an international team of researchers and artists. The paper shows how the photographs taken as part of the ‘Air of the Anthropocene’ project – created by artist Robin Price and University of Birmingham environmental scientist Professor Francis Pope – had stimulated discussion around the impact of air pollution. 

“Air pollution is the leading global environmental risk factor,” said Professor Pope. “By painting with light to create impactful images, we provide people with an easy-to-understand way of comparing air pollution in different contexts – making something that was largely invisible visible.”

Photographer Robin Price commented: “By providing a visual understanding of air pollution that is accessible to people who don’t necessarily have a scientific background, the light painting approach can demonstrate that managing air pollution levels can have a significant impact on people’s day-to-day lives.”

The team used the air pollution sensors to measure PM mass concentrations and took the sensors’ real-time signal to control a moving LED array programmed to flash more rapidly as PM concentration increased. A long-exposure photograph is taken with the artist moving the LED array in front of the camera – the flash becoming a dot on the photograph. The artist is not seen in the photo because they are moving, but light flashes from LEDs are seen because they are bright. If more light dots appear in the photographs, it means the PM concentration is higher.

“Air of the Anthropocene creates spaces and places for discussion about air pollution, using art as a proxy to communicate and create dialogues about the issues associated with air pollution,” explained Professor Pope.

Co-author Carlo Luiu, from the University of Birmingham, added: “Thanks to the power of images, we can provoke people’s emotions – fostering awareness and prompting people to share their perspectives and take action to tackle air pollution.”

The Air of the Anthropocene project has exhibited at gallery shows in Los Angeles, Belfast, and Birmingham. The project has also been used to raise air pollution awareness by the UN International Organization for Migration (IOM), the Foreign, Commonwealth, and Development Office (FCDO), and UN-Habitat, which commissioned four pollution light paintings and texts to be displayed in Kampala, Uganda.

The World Health Organisation (WHO) estimates that 99 per cent of the global population breathe polluted air, causing about 7 million premature deaths worldwide each year.

The situation is particularly challenging in Asia, where air pollution remains a major problem in countries such as India and China, despite efforts to implement a number of air quality policies and measures. African countries have also experienced significant deterioration in air quality over the past five decades.

Particulate matter is the air pollutant most responsible for human morbidity and mortality. It impacts physical health in multiple ways and is responsible for diseases including heart disease, stroke, and cancers.