Pollutionwatch: January 2007

January was mainly wet and windy across the UK, with little in the way of pollution. Aside from an unseasonal ozone episode in Edinburgh on the 14th, the only notable pollution came in the last week of the month when the weather calmed down and high pressure brought comparatively dry and still air to England. These conditions allowed particle levels to rise over London, with air quality standards being exceeded at a number of roadside monitoring stations. Last month saw the release of the government's air quality indicator for sustainable development. The figures are provisional until around April, by which time all the data from the 100+ monitoring stations will have been fully checked, or ratified. However, the early indication is that last year was one of the most polluted years in the last decade - and is comparable to, or even worse than, 2003 when the protracted summer heatwave led many to consider it as 'extreme' in terms of pollution levels. Although 2006 saw fewer days when concentrations of ozone or particles breached standards (when pollution is classed as moderate, high or very high), over the whole year concentrations of particles at roadside sites were the highest since 1997 and ozone levels at urban background locations were the highest on record (since 1992). Much of this was associated with the hot weather in June and July. Current predictions for climate change indicate that although the weather in the UK is likely to generally get windier, when these summer heatwaves do occur they will be stronger and more persistent leading to both more polluted days and higher peak concentrations of pollutants.