Ground Level Ozone Concentrations1: 1990-2012
Ozone in the stratosphere forms a layer that protects the Earth against harmful ultra-violet radiation, but tropospheric (ground level) ozone is a damaging oxidant. Exposure to high ozone concentrations can cause respiratory damage, and affects vegetation by damaging leaves and reducing yields.
Ozone is formed by a slow, complicated series of reactions from other pollutants that may be blown over from Europe. The most important man-made precursors are nitrogen oxides and volatile organic compounds produced by road transport, industrial processes and solvent use. Ozone concentrations tend to be lower in urban areas where it is converted to nitrogen dioxide by reacting with nitrogen oxides.
The Air Quality Strategy5 objective for ground level ozone concentration (to be met by 2005) states that the maximum daily concentration (measured as an 8-hour running mean) of 100µg/m3 should not be exceeded more than 10 days per year. In 2012, this objective was met at 8 of the 9 sites.10 The site that failed was Strath Vaich. Strath Vaich regularly fails to meet the AQS objective, most recently failing in the periods 2005-08 and 2011-12.
Email: Callum Neil