10th International Aerosol Conference September 2 - September 7, 2018 America's Center Convention Complex St. Louis, Missouri, USA
Abstract View
Fine-scale Spatio-temporal Variation in Particulate Matter in a Small Wood-burning Town Revealed by a Network of Continuous Low-cost Sensors
Ian Longley, Gustavo Olivares, Sam Edwards, GUY COULSON, National Inst of Water and Atmospheric Research, New Zealand
Abstract Number: 939 Working Group: Aerosol Exposure
Abstract Following a co-location study, 15 monitoring nodes, based on the Plantower 3003 dust sensor, were deployed across a small New Zealand town for a minimum of 19 days in winter 2016. Rangiora has previously been identified as a town where wintertime concentrations of particulate matter breech the National Environmental Standard of 50g m-3 over 24 hours, and emissions are dominated by wood combustion for home heating. The location of the town on a coastal plain in the lee of a mountain range leads to complex air flows especially at dusk when nocturnal boundary layers form and emissions peak.
The sensors were initially co-located with a TEOM-FDMS operated by the regulatory authority. PM2.5 concentrations were then measured every minute at the 15 locations distributed across the town (area approx. 17 km2, pop. 17,000) for 19 days (and at some of the sites for longer). This was supported by the deployment of three temporary automatic weather stations on the periphery of the town. A further co-location study was conducted at the end of the campaign.
All 15 sensors reported valid data throughout the campaign. The co-location study revealed high correlation between the Plantower sensors and the TEOM-FDMS with very stable performance. No interferences were detected (e.g. related to air temperature or humidity). The sensitivity of each individual sensor varied but was sufficiently stable to be adjusted for with a simple linear function.
On average the data revealed a large degree of spatial variation in concentrations across the town. The spatial variation was not consistent over time but highly complex. A tendency for concentrations to peak earlier in the east and later in the west was observable and broadly consistent with shifts in wind direction. Inspection of the time series indicated that some sites were subject to temporary elevations in concentrations (anomalies with respect to typical or larger-scale patterns) that imply localised near-source and plume-strike impacts.