Investigating Air Quality- Black Carbon v Nitrogen Dioxide ratios at Glasgow High Street & Townhead.
Channel: Sam Grainger
Date: 2020-10-10

The World Health Organisation (WHO) considers air pollution to be a global threat to public health.  To better understand air pollution across Glasgow, the government set-up a series of Monitoring Stations which measure air pollutants including Oxides of Nitrogen and Black Carbon.  Two notable Monitoring Stations in Glasgow are at High Street and Townhead; the former station measures air quality at the kerbside and the latter measures urban ambient air.  The supply of air pollutants at both stations is conjectured to be from vehicular emissions, though the precise sources of air pollution have never been identified.  This work uses the R’ Studio’s ‘Openair’ Toolset to help detect and quantify the subtle contribution of Black Carbon (BC) and Nitrogen Compounds to Monitoring Stations.  A simple normalised plot was used to understand the temporal variation in Black Carbon and Nitrogen Compounds on various scales.  Analysis of the spatial characteristics of the sources relies on a series of bivariate polar plots, which help to discriminate the sources of pollutants based on their meteorological profile (wind direction and speed).  Besides pollutant specific polar plots, ratios of BC to Nitrogen were used to find vehicular sources (high in Nitrogen vs BC).  Also, Conditional Probability Function (CPF) polar plots helped to gain an understanding of the consistency of the source, given certain meteorological conditions.  This analysis was useful in identifying minor sources of air pollution at these Monitoring Stations, with several unknown sources of air pollution identified.  At High Street, the station was affected by a local brewery, car parking, and several major roads.  The M8 Townhead intersection, Buchanan Bus Station, nearby roads, and car parking affected the Townhead station.  Overall, this work provides an approach that would help to scope, confirm, and refine sources of Nitrogen and BC supply at Monitoring Stations on the AURN Network.