The first-ever visual representation of global concentrations of a significant air pollutant that impacts human health has been developed by a group of scientists.
The first-ever visual representation of global concentrations of a significant air pollutant that impacts human health has been developed by a group of scientists.
Created by researchers from the University of Leeds, the University of Edinburgh, North Carolina State University, and the UK Met Office, the Air Quality Stripes provide a stark comparison between the notable improvements in air quality in much of Europe and the worrying decline observed in parts of Africa and Central Asia.
The findings from this project underscore both the accomplishments and the persistent difficulties in addressing air pollution on a global scale.
Dr. Kirsty Pringle from EPCC at the University of Edinburgh, who is a co-director of the project, stated, “Air pollution is often referred to as the ‘invisible killer’, but these visuals bring visibility to what is typically unseen, illustrating the shifts in particulate matter pollution over the decades.”
Dr. Jim McQuaid, an Associate Professor of Atmospheric Composition in the Leeds’ School of Earth and Environment, who collaborated on the Air Quality Stripes project with Dr. Pringle, commented, “Essentially, air pollution ranks among the top global risk factors for mortality, thought to be responsible for one in ten deaths worldwide.”
“Our Air Quality Stripes depict the significant variation in trends and concentrations globally. The stripes highlight that there is still considerable work required to minimize people’s exposure to poor air quality, and in some regions, a substantial amount is needed!”
Taking inspiration from the well-known climate warming stripes imagery, the researchers designed their own visual to depict the changing trends in outdoor concentrations of particulate matter air pollution, which consists of tiny liquid or solid particles like dust, dirt, soot, or smoke found in the atmosphere.
Dr. Steven Turnock, a senior scientist from the UK Met Office who assisted with the data for the Air Quality Stripes project, remarked, “Presenting this scientific data as Air Quality stripes effectively accentuates the sharp differences in air quality trends and the extent of poor air quality exposure based on geographical location.”
The project includes stripes for the capital city of every country worldwide, with two additional cities from China, India, and the United States. The research team also incorporated their cities, Leeds, Edinburgh, and Exeter.
The lightest blue stripes align with the World Health Organization’s Air Quality Guidelines set in 2021, while all other colors exceed these guideline values.
By combining data from computer simulations and satellite observations, the researchers estimated the changing concentrations of particulate matter since the start of the industrial era. An artist developed the color palette by analyzing over 200 online images tagged with “air pollution” to identify the prevailing color schemes.
Key Findings:
- Air Quality Improvements in Europe: The visuals reveal significant reductions in particulate matter levels throughout most of Europe, particularly Western Europe. Stricter regulations and technological advancements have effectively lowered particulate matter concentrations in major European cities such as London, Brussels, and Berlin.
- Declining Air Quality in Central Asia and Africa: The representations indicate a troubling increase in particulate matter pollution in numerous cities in Central Asia and Africa, including Islamabad, Delhi, and Nairobi. Rapid urbanization, industrial development, and insufficient regulatory frameworks are driving this alarming trend, posing substantial health risks to local residents.
- Global Inequalities: The images showcase the stark disparities in the progress of air quality across various regions, highlighting the urgent need for targeted international efforts to combat the rising air pollution crisis in the most affected areas.
- Influence of Natural Sources: Noteworthy influences from natural sources, such as desert dust and wildfires, were evident in certain locations, with areas like Jakarta showing lower levels of pollution than anticipated due to their proximity to the coast.
A mixture of pollutants
Particulate matter, or PM2.5, has a diameter smaller than a 30th of a human hair and can easily penetrate deep into our lungs. The tiniest particles can enter the bloodstream, impacting our health; some have even been found in the blood of unborn children.
These particles can originate from natural events like volcanic eruptions and deserts but are also produced by human activities, including industrial processes, automobiles, agriculture, residential burning, and climate change-related fires.
PM2.5 is associated with a broad spectrum of health complications, ranging from respiratory issues such as asthma to deteriorated lung health, higher risks of cancer and heart disease, and an increased susceptibility to various ailments like diabetes, Alzheimer’s, and Parkinson’s disease.
The World Health Organization advises that the annual average concentration of PM2.5 should not exceed 5 micrograms per cubic meter of air (5 ug/m³). This guideline represents a level classified as very good air quality. It’s essential to recognize that medical science does NOT acknowledge any safe level of PM2.5. Currently, 99% of the global population lives with levels above this threshold, with the highest PM2.5 concentrations typically found in low- and middle-income countries.
The AQ stripes utilize an annual average to accommodate the fluctuations caused by variations in weather throughout the year, simplifying comparisons across locations. Nevertheless, the researchers emphasize that even brief exposure to elevated levels can lead to immediate health concerns necessitating medical attention.
Dr. McQuaid added, “We created these to distill complex data generated by computer models into something far more understandable.”
“Interestingly, one of our major challenges was determining the color scheme. We ultimately settled on blue to black, representing a spectrum from clear blue skies to black for extremely high pollution levels.”
“In the end, we reached out to a colleague in the US (Douglas Hamilton) who collaborated with his team to create a color palette using online images tagged ‘air pollution’, which aligned closely with what we originally designed, but it was reassuring to receive external validation.”
“To me, it’s about that moment of realization when someone comprehends the information; that sudden, ‘oh, now I get it!’ I aimed to make it straightforward enough that individuals without a scientific background could grasp it without needing advanced knowledge.”
Dr. Pringle remarked, “The visuals demonstrate that reducing air pollution is achievable; the air quality in many European cities has markedly improved over the past century, benefiting public health. We truly hope similar advancements can be realized across the globe.”
The Air Quality Stripes continue the tradition of the Climate Warming Stripes, initiated by Professor Ed Hawkins at the National Centre for Atmospheric Science and the University of Reading in 2018, which have since become widely recognized as a visual representation of the warming planet.
Professor Hawkins’ work has also inspired the creation of visuals depicting biodiversity loss and ocean acidification.
