7.4.1 An air quality “headline” indicator was introduced in 1999 in support of the UK Sustainable Development Strategy. When this strategy was updated in 2005, a new air quality indicator was included, better reflecting the effects on health of long term exposure to lower levels of pollution. The indicator is split into two
1. Annual exposure to pollutants
7.4.2 There are nine automatic air quality monitoring sites in the South West. Full details and downloadable data on the last hour's data, weekly graphs, site information and UK background concentration data is available from the Air Quality Archive. Detailed air quality statistics are available from Defra.
2. Number of days when levels of pollutants are moderate or higher
7.4.3 Weather can cause significant variation from year to year in the number of days of moderate or higher air pollution. The hot summer and other pollution episodes in 2003 and 2006 led to an unusually high number of pollution days.
7.4.4 In 2008, urban areas in England recorded 26 days of moderate or higher air pollution on average per site, compared with 23 days in 2007, and 59 days in 1993. This series has shown a high degree of year-on-year variability. Nationally, rural areas recorded 45 days of moderate or higher air pollution on average per site, compared with 30 days in 2007, also showing significant fluctuations over time.
7.4.5 In the South West, Bournemouth and Bristol St Pauls were monitored urban sites in 2008, recording 65 and 33 days of poor air quality respectively. As with the national trend, these two sites have shown significant variability. However, between the number of poor air quality days increased by 11 days in Bournemouth between 2007 and 2008 and by 1 day in Bristol St Pauls. 7.4.6 Only Yarner Wood was monitored for rural air quality in the region in 2008, which recorded 36 days of poor air quality. Although this was eight days below the national average and seven days below the 2007 figure for the region, there is no clear trend in rural air quality due to significant year-on-year variability.
Figure 7.4.1 Days with moderate or higher air pollution in the South West with England & Wales comparison
7.4.7 Full analysis of air quality in the South West is available on the South West Environment website. See also the sections on Local Environmental Quality Management Areas and emissions from transport in the 5.4 'Traffic Flow' chapter of this website.