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Trends - Air Quality Indicators

Part of the Government's plans to ensure a better quality of life are Indicators of Sustainable Development. These include a range of indicators based on air quality, one of which is the "Air Quality Headline Indicator". This is the average number of days per year on which air pollution is measured as "moderate" or worse (i.e. "moderate", "high" or "very high") according to the Air Pollution Information Service bandings used in weather forecasting.

Headline Indicator - Urban and Rural Averages

This graph shows the average number of days (per monitoring site) with moderate or higher pollution according to the Air Pollution Information Service bandings. At the "moderate" level, the effects of pollution may start to be noticeable to sensitive people.Click on the image below to open a larger version in a new window.

Graph showing the Rural and Urban Averages
This graph shows no overall clear trend in rural pollution days since 1997, although peaks for 'heat wave' summers such as 2003 and 2006 are clearly seen. This is because most incidences of poor air quality in rural areas are due to high concentrations of ozone, which are dependent on meteorological factors. There appears to be a decreasing trend in overall urban pollution days since the mid 1990s, although this trend should be interpreted with caution because the number, and distribution, of monitoring sites has changed substantially in recent years. The number of urban sites on which this indicator is based has risen from just three in 2000, to 17 in 2010.