Local weather data (wind direction, wind speed and temperature) from meteorological stations and daily synoptic data have been examined in relation to airborne particulate material (PM10) concentrations recorded at 17 pollution monitoring sites throughout Kent for the period 2000 to 2008, as an aid to understanding dispersal patterns in relation to topography. In general, local and synoptic wind direction patterns followed the same trends: the yearly distribution is dominated by southwesterly winds, followed by winds from the west and the northwest. Detailed analysis of local wind patterns at four sites (two coastal and two inland) strongly suggested the presence of seas breezes, reaching maximum frequency between March and August and fewest occurrences between November and February. Transport of PM10 over 30 km inland was also inferred. In addition to local wind transport, the location of the pollution monitoring sites and their environment are key to explaining the differences in PM10 concentrations recorded between the sites. The 10 sites located on roadsides registered the highest number of particle counts, followed by the five sites located within urban areas. The lowest amount of particles was found at the two rural sites. The five roadside sites closest to London (two in Gravesham and three in Dartford) exceeded the daily recommended amount of 50 μg/m3 several times each month, probably reflecting the increased road traffic in those areas. Aside from the variation in PM10 amount between sites, seasonal differences were also observed, with the lowest amount of PM10 recorded in the autumn and the highest in spring. Episodes of pollution affecting the whole of Kent were also observed. These were more clearly related to the synoptic situation rather than any local wind variations and appear to indicate regional or trans-boundary pollution transport. The latter is also supported by preliminary evidence from a PM10 trap sampling at a site on the south coast.
Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:547160 |
Date | January 2011 |
Creators | Perea, Virginia Nicolas |
Contributors | Burt, Peter |
Publisher | University of Greenwich |
Source Sets | Ethos UK |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
Source | http://gala.gre.ac.uk/7133/ |
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