Tropospheric Ozone Assessment Report: Present-day Tropospheric Ozone Distribution and Trends Relevant to Vegetation

This article summarizes the Tropospheric Ozone Assessment Report (TOAR-Vegetation), which analyzes ozone distribution and trends across over 3,300 vegetated sites globally using three specific metrics (M12, AOT40, and W126) to assess impacts on vegetation.

• The report identifies the highest mean ozone values between 2010 and 2014 in the northern hemisphere's mid-latitudes, specifically in the southern USA, the Mediterranean basin, northern India, Japan, the Republic of Korea, and parts of China (north, north-west, and east). Conversely, the lowest values were found in Australia, New Zealand, southern South America, and parts of Canada, the USA, and northern Europe.
• Regional trends from 1995 to 2014 varied by geography: North America (NAM) saw a significant decrease in ozone, East Asia (EAS) experienced a significant increase, and Europe (EUR) showed no change. Additionally, wheat growing areas in East Asia had significantly higher AOT40 and W126 values compared to those in Europe (p < 0.05), though this difference was not observed in rice growing areas.
• To improve future global assessments of ozone's impact on vegetation, TOAR-Vegetation recommends increasing ozone monitoring and field evidence collection, studying mountain/upland and peri-urban agricultural areas, adding meteorological and inlet height data to the dataset, creating new region-specific damage thresholds, and integrating observations with modeling of stomatal uptake.

APA

Stockholm Environment Institute (2018). Tropospheric Ozone Assessment Report: Present-day Tropospheric Ozone Distribution and Trends Relevant to Vegetation. https://www.sei.org/publications/tropospheric-ozone-assessment-report-present-day-tropospheric-ozone-distribution-trends-relevant-vegetation/

Chicago

Stockholm Environment Institute. Tropospheric Ozone Assessment Report: Present-day Tropospheric Ozone Distribution and Trends Relevant to Vegetation. 2018. https://www.sei.org/publications/tropospheric-ozone-assessment-report-present-day-tropospheric-ozone-distribution-trends-relevant-vegetation/.

Wikipedia

{{cite report |author=Stockholm Environment Institute |title=Tropospheric Ozone Assessment Report: Present-day Tropospheric Ozone Distribution and Trends Relevant to Vegetation |date=28 June 2018 |url=https://www.sei.org/publications/tropospheric-ozone-assessment-report-present-day-tropospheric-ozone-distribution-trends-relevant-vegetation/ |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{stockholmenvironmentinstitute2018tropospheric, author = {{Stockholm Environment Institute}}, title = {{Tropospheric Ozone Assessment Report: Present-day Tropospheric Ozone Distribution and Trends Relevant to Vegetation}}, institution = {Stockholm Environment Institute}, year = {2018}, month = jun, url = {https://www.sei.org/publications/tropospheric-ozone-assessment-report-present-day-tropospheric-ozone-distribution-trends-relevant-vegetation/}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }