Air pollution has long been a problem in London, and the current mayor has identified pollution as one of his major goals to highlight and tackle polluion, and improve the capital’s air quality during his time in charge. This map, of the modelled 2020 annual pollution levels of NO2, has been produced by Parallel, using the London Atmospheric Emissions Inventory 2013 (LAEI) dataset that was published by the Greater London Authority in 2016 (they have since published a slightly updated version). The calculated data is presented as a raster (a grid of estimated pollution values) and Parallel have taken this and made it into an 3D webmap, so that you can “fly around” the map and see towers of pollution – and troughs of fresh, clean air:
There’s something quite compelling this kind of presentation – it works well because this kind of pollution is dominated by, and generally restricted to, major roads. The 3D spikes therefore don’t obscure the rest of the map, as they are generally constrained to quite linear features. They act to both emphasise the significant and scary nature of pollution in some areas, and illustrate that, by walking or cycling through back streets rather than on main roads, your pollution intake can be significantly lowered. One striking element, on examining the map, is where elevated sections of road, such as the Hammersmith Flyover, the Westway and the bridges across the Thames, are pollution hotspots – the height meaning that the surrounding environment is further away and so can less effectively absorb the pollution: