Kolkata Pollution Dataset
Home About Publication Ethical Documentation Sensor Calibration Novelty Dataset

We are working with Aerogram, an IIT-Delhi incubated startup, which is involved in assembling its own low-cost AQM devices. The device we are currently using in our buses is EzioMotiv which is a robust spatiotemporal data collection device allowing the measurement of particulate matter (PM1.0, PM2.5, PM10.0) along with other data. The datasheet for the PM sensor (PMS 7003) used in this device is available here: [PDF]. PMS7003 comes from Beijing and was chosen because of its relatively higher accuracy in measuring PM values when compared to other low cost sensors [2]. However, we additionally correlate our sensors with CAAQMS colocated sensors too.

Calibration with CAAQMS sensor

  1. Pollution Sensor placements in Kolkata region

    CAAQMS sensors are in Black, whereas our Low Cost Static Sensors are in Green. The traces in red/orange/yellow colours depict the trajectories covered by different buses having our low cost mobile sensors. Red colour depict high PM2.5 whereas orange/yellow depict relatively lower PM2.5

  2. Number of hourly samples available in the datasets (Y-axis) for different low-cost sensors (X-axis) for Sep15-Oct31 2023

    Some sensors are facing power / network connection / maintenance issues and hence less data is available for such sensors.

  3. CAAQMS Data vs Low-Cost Sensor Data for an arbitrary day (Dec 15, 2023)

    Most of the low-cost sensor data is showing relatively higher PM2.5 as compared to CAAQMS data, which signify need for calibration.

  4. Sorted mean PM2.5 plot for different LCS locations (in blue color)

    Some locations experience higher absolute PM due to hyper-local factors. The orange location (VP) is a reference CAAQMS sensor for selected for the calibration purpose.

References

  1. Stavroulas, Iasonas, Georgios Grivas, Panagiotis Michalopoulos, Eleni Liakakou, Aikaterini Bougiatioti, Panayiotis Kalkavouras, Kyriaki M. Fameli, Nikolaos Hatzianastassiou, Nikolaos Mihalopoulos, and Evangelos Gerasopoulos. 2020. "Field Evaluation of Low-Cost PM Sensors (Purple Air PA-II) Under Variable Urban Air Quality Conditions, in Greece" Atmosphere 11, no. 9: 926. https://doi.org/10.3390/atmos11090926

  2. Bulot, F.M.J., Johnston, S.J., Basford, P.J. et al.Long-term field comparison of multiple low-cost particulate matter sensors in an outdoor urban environment.Sci Rep 9, 7497(2019). https://doi.org/10.1038/s41598-019-43716-3