Author(s): Fleming Z.L., Doherty R.M., von Schneidemesser E., Malley C.S., Cooper O.R., Pinto J.P., et al

Year: 2018

In: Elementa: Science of the Anthropocene. 6(1):12

DOI: 10.1525/elementa.273

Type: Journal article



Link to SEI author:

Tropospheric Ozone Assessment Report: Present-day ozone distribution and trends relevant to human health

Present day non urban ozone levelsFigure1 Uni.Leics
Global map of present-day ozone levels in non-urban areas (Uni of Leics): 

This article presents research led by the Universities of Leicester and Edinburgh and 12 other research institutions into surface ozone levels that are important for human health  

Ozone found at the Earth’s surface (the troposphere) is an air pollutant harmful to human health.  The regulatory ozone limit values designed to protect human health vary by country. The research conducted was a component of the Tropospheric Ozone Assessment Report (TOAR), an international effort to improve scientific understanding of ozone’s global distribution and trends. The results provide the most ambitious ever ground-level ozone assessment, using data from over 4,800 monitoring stations across the globe.

As part of the study, ozone levels potentially detrimental to human health were assessed where data was available, both in urban and non-urban areas worldwide. There is considerable variation within regions and hot-spot locations with the highest ozone levels have been identified.

This study uses a variety of ways of measuring the occurrence of high ozone levels to assess the frequency of periods a given population is exposed to harmful ozone levels and how this has changed over time. 

Surface ozone levels potentially detrimental to human health are found in many regions around the globe, both in urban and non-urban areas. They found that different methods of determining high and peak ozone levels worldwide are generally similar.

While ozone has decreased in much of Europe and the North America over the past 15 years, the study shows it is increasing in parts of East Asia with increasing development and pollution emissions.  A large publicly available database has been compiled which includes a complete set of statistics and graphics available for viewing and download.

Read the article (external link to journal website)