In which cities in Spain did air quality improve most in 2021?

At the beginning of the year, the Sustainability Observatory presented a relevant report on air quality in Spain in 2021.

Last January, the Sustainability Observatory published a revealing report analysing which cities had most improved their air quality, which were the most polluted, and what post-Covid effects had been found in Spain’s 80 most populated cities.

In this analysis, the evolution of the three key pollutants NO2, PM10 and PM2 was reviewed. In 2021, the levels were very similar if we take all cities together, with an average of 19.7 µg/m3 NO2 in 2020 and 2021, and between 18-20 µg/m3 for PM10 particles. It is interesting to note that the NO2 levels during the first confinement in Spain were 11 µg/m3.

Towards the end of the year, an increase in pollution was also noted, as a result of a further relaxation of urban mobility restrictions. An increase in NO2 concentrations in small cities in 2021 compared to 2020.

Which Spanish cities improved their NO2 levels in 2021?

If we look at the data on NO2 levels in cities with more than 500,000 inhabitants, the big winner is Valencia, with 15% less emissions. Malaga also catches the eye, which reduced its NO2 levels by 6%. If we focus on intermediate cities, from 250,000 to 500,000 inhabitants, Murcia is striking. The city reduced its emissions by 38%.

Also noteworthy is Alicante (-11%) and Palma de Mallorca (-7%), which may have been influenced by the fact that the tourist density in both cities was not yet the same as in pre-pandemic levels. The opposite was the case in Vigo (14%) and Valladolid (15%).

Focusing on cities with less than 250,000 inhabitants, NO2 levels improved considerably in Castellón de la Plana (-25%), Cartagena (-21%) and Logroño (-15%), while in those that make up the group of smaller ones include Gandía (-27%), Palencia (-23%) and Avilés (-21%).

Which cities in Spain improved their PM10 and PM2.5 levels in 2021?

If we focus on PM10particles, Las Palmas (-45%), Valencia (-27%), Arrecife (-23%) and Valladolid (-13%) are the ones with the best air quality for this type of pollutant. Valencia, as we have already mentioned, also saw a significant reduction in NO2 pollution.

If we focus on PM2.5particles, the cases of Cartagena (35%), Seville (20%), Alcalà de Henares (-18%), Murcia (-16%), Avilés (-14%), Valencia (13%) or Torrevieja (-12%) are noteworthy.

2022, decisive in shaping the state of pollution in Spanish cities

Now that two years have passed since the start of the pandemic and mobility in cities seems to be increasingly returning to a pre-pandemic state, it will be important to observe if in 2022 this significant decrease in pollution detected in the last two years returns to the levels of yesteryear, or if measures such as the implementation of ZBE and the new mobility dynamics, with the greater use of scooters and bicycles, definitely confirm that cities are on the right track. As a revealing fact, NO2 levels between 2017 and 2019 in Spanish cities were 22 µg/m3, while in the 2020-2021 period it was 16 µg/m3, 27% less.

For our health and that of the planet, at Mobility by Cycling Friendly we hope that 2022 will be the confirmation of the paradigm shift in urban mobility.

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