Within: Air Quality

This report was produced as part of the Bath and North East Somerset Air Quality Hack held on 21/09/2014 by Leigh Dodds whose analysis is reproduced with thanks.

Bath Air Quality Report – London Road AURN (1997-2013)

The report shows levels of nitrogen-oxide pollutants for the period 1997-2013. The report used data from the London Road AURN site.

Wind Speeds and Direction

The following diagram, known as a wind rose plots the frequency of wind speed/direction frequencies. Longer slices indicate directions from which stronger winds are more frequently found. The slices are colour coded based on the wind strength.

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The following diagram shows the same information, but broken out by season of the year.

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Insight: The prevailing winds in Bath are from the west and south-west. However earlier in the year, winds are more often found from an easterly direction.

Pollution Times

Levels of pollutants often vary with the time of day, week and season. This is particularly true for man-made pollutants. The following diagrams show this information from a number of perspectives.

How do pollutant levels vary by time of day?

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Insight: Nitrogen oxides levels in Bath are highest at early morning and late afternoon. Levels are highest in the week and lower at weekends.

The following calendar views show which days of the year had the highest levels of Nitrogen Oxides for the start and end of the reporting period.