Ground-level ozone in much of Europe and North America has decreased over the last 15 years, but is on the rise in parts of East Asia, a major study published this week has claimed.
The research, led by Dr ZoÑ‘ Fleming from NCAS (based at the University of Leicester) and Professor Ruth Doherty from the University of Edinburgh, has analysed ground-level ozone data from over 4,800 monitoring stations in urban and non-urban areas worldwide.
Ozone is formed in the atmosphere from emissions of pollutants such as nitrogen oxides from vehicles, organic compounds from solvent use, and methane from agriculture.
Once formed, ozone can stay in the atmosphere for weeks and travel long distances from emission sources, across countries and continents. When it reaches ground-level ozone can cause significant harm to human health.
The studyâ€™s findings will contribute to the Tropospheric Ozone Assessment Report (TOAR), an international effort to improve scientific understanding of ozoneâ€™s global distribution and trends.
Dr ZoÑ‘ Fleming, said: â€œTOAR is the most ambitious project to date to assess global ozone levels at the surface of the Earth, helping us to better understand potential human health impacts.
â€œDespite improvements in air pollution emissions in Europe and North America, ozone levels that are harmful to human health are still a cause for concern across the world and ozone is rising in East Asia.
â€œThere is an increasing awareness of the issues of human health from poor air quality and making such a database freely available and disseminating the results from the study will inform the public on the health implications of ozone.â€
Institutes involved in the ozone level analysis included the Institute for Advanced Sustainability Studies (IASS) and Forschungszentrum JÃ¼lich in Germany, the Universities of Colorado, North Carolina-Chapel-Hill, and Maryland as well as A.S.L. and Associates in the US, the Stockholm Environment institute in the UK, INERIS in France, the Chinese Academy of Meteorological Sciences and Chinese Academy of Science in China, NILU in Norway, Chalmers University in Sweden and the University of Witwatersrand in South Africa.
The research was funded by the International Global Atmospheric Chemistry project (IGAC), the World Meteorological Organization (WMO), the National Oceanic and Atmospheric Administration (NOAA) and Forschungszentrum JÃ¼lich.
Studies have linked exposure to ground-level ozone to conditions such as lung inflammation, decreased lung function and an increase in asthma attacks.
Research published in summer 2017 by the Unversity of Yorkâ€™s Stockholm Environment Institute suggested that as many as 1 million premature deaths every year can be linked to air pollution (see airqualitynews.com story).