Watch any recent news bulletin on the causes of city centre air pollution and you will quite rightly have seen an accusing finger pointing straight at vehicle fumes. But it is the combination of weather and pollution that can have a long term effect on health. So local authority highways and environmental departments are looking much further than the end of a car exhaust to predict air quality conditions.
Leeds City Council has been building up a complete picture of weather conditions using one of the new Climate Data Loggers (CDL) from Campbell Scientific.
The weather station is mounted on a 30m mast, sited in an open location close to the centre of Leeds. 'Wind speed, direction and temperature are collected at several heights, together with ground level data for relative humidity, solar radiation and rainfall,' says Leeds group engineer David Cherry. 'These weather parameters provide crucial information regarding the dispersion mechanism for pollutant sources.
'Weather data can also provide useful diagnostic information,' he continues, 'which can indicate sources of pollution. For example, power station plumes in the Vale of York can affect air quality in Leeds during specific weather conditions. High pollution episodes recorded by air quality monitoring sites within Leeds can often be explained by specific weather conditions. The presence of temperature inversions, indicated by an increase in temperature with height, can effectively trap pollutants below the inversion layer.
'Also weather parameters such as wind speed, direction and temperature all significantly affect the propagation of sound. Often, nuisance complaints can be explained, or the source mitigated through knowledge of local weather conditions,' he concludes.
Meanwhile in Middlesbrough, another CDL sits on the roof of a local secondary school. The council's public protection and trading standards department, in partnership with the Meteorological Office, chose the location because it was on an open site in central Teesside.
'We've developed a good dialogue with all sectors of the community,' says Middlesbrough council technical officer Jeff Gray. 'Weather data helps us improve the accuracy of our findings - and calling up accredited Met Office weather details on the computer has enhanced the way in which we provide a service to local people, who can still play a vital role in complaint investigation work by simply keeping records of dates and times they've encountered any pollution problems.'
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