HADES: Annual-average air pollution concentrations in England and Wales (2018-2020)

This resource contains national-scale outdoor nitrogen dioxide (NO₂) and ozone (O₃) exposure surfaces for England and Wales in 2018, 2019, and 2020 at very high spatial resolutions (10m and 100m). These exposures are also summarised for the 2021 UK Census Output Area (COA) communities, using population-weighted (residential) and area-weighted (community spaces) sampling techniques.

The exposure surfaces were created using the HADES: Hybrid Air Dispersion Exposure System modelling framework, which combines dispersion modelling with satellite-derived estimates of background concentrations, land cover, and a 3-D representation of buildings, in a statistical calibration framework.

The 10m annual-average concentration surfaces reported r-squared (goodness-of fit) values of 0.80 for NO₂ and 0.86 for O₃, with respect to measurement data at 136 locations in the UK governments automatic monitoring network. The same annual-average NO₂ and O₃ surfaces are associated with root mean squared error (RMSE) values of 4.90 µg/m³ and 3.17 µg/m³, respectively.

The air pollution surfaces and their associated data are freely available for non-commercial use (CC BY-NC 4.0) under the condition that the following source is cited:

Jephcote, C., and Gulliver, J. (202x). Development and evaluation of rapid, national-scale outdoor air pollution modelling and exposure assessment: Hybrid Air Dispersion Exposure System (HADES). [In peer review]