Mobile AQ mapping: a tool for increased spatiotemporal understanding of urban AQ

Mobile monitoring can be used as an additional tool to collect air quality data at a high spatial resolution and to complement data from fixed air quality stations. The data can be used to get insights in spatio-temporal variability within urban areas to identify  hot-spots, support health studies, evaluate mobility plans, evaluate the exposure of cyclists as a function of cycling infrastructure and perform model validation.

When applying mobile mapping, it is important to use high-quality instruments and apply the correct measurement methodology (number of repetitions, season), data processing and validation to obtain meaningful data. In addition, engaging citizens in data collection can results in increased data collection and awareness raising.

As part of the RI-URBANS project (https://riurbans.eu/) mobile mapping tools were developed and tested in different European pilot cities.

This study presents outcomes from mobile monitoring campaigns with citizens carrying portable instrumentation for black carbon (BC), ultrafine particles (UFP) and particulate matter (PM) in Rotterdam (NL) and Warsaw (PL). Results show spatiotemporal and seasonal variability of the quantified urban pollutants and allowed identification of specific cold- and hotspot locations encountered by commuting cyclists within the sampled cities.

The data processing workflow will be explained including (i) instrument validation, (ii) spatial aggregation and (iii) temporal correction procedure. Moreover, sensitivity analyses were conducted on the mobile data to derive the number of required repeated measurements to approximate the long-term average road segment exposure.

The paper will present good practice of mobile mapping and illustrate with some results in different cities.