The data consist of air pollution (particulate matter) sensor readings, generally at half-hour intervals, for various locations, generally road-side, in the City of Liverpool. They sense temperature and humidity, as well as PM1, PM2.5 and PM10 particulate matter concentration measurements. The sensors are supplied and maintained by Aeternum Innovations on behalf of CDRC and the University of Liverpool.

As well as data for a number of sensors that have been installed since late 2021/early 2022 across the city, the data from a new set of sensors along a linear bus route, the 10A, which were installed at the end of 2023, are also available. The 10A bus route is one of the city's busiest and is in the process of being converted to hydrogen bus operation.

Content

The data is in the form of one CSV file for each sensor and time period (historic to end of 2023 and quarterly onwards), and one metadata file with locations, names and IDs for each sensor. Variables include date and time, temperature, humidity, PM1.0, PM2.5 and PM10.

Quality, Representation and Bias

Each sensor has been professionally installed and calibrated by Aeternum Innovations.

The pre-existing sensors have good spatial coverage across Liverpool, but with a focus on the city centre.

The raw data is obtained by Professor Jonny Higham from the School of Environmental Sciences at the University of Liverpool, who has cleaned and interpolated the raw data, to fit it in to the regular time intervals, also removing or correcting obviously faulty data, and making it available via a web portal.

The temporal granularity is typically every 30 minutes, normally every 15-60 minutes, with some prolonged data gaps.