Europe: NO₂ concentrations in select cities 2023

Lockdowns and other measures caused by the outbreak of the coronavirus in 2020 resulted in lower traffic levels in some of the world's busiest cities. The reduction in traffic led to reduced concentrations of harmful pollutants such as nitrogen dioxide (NO₂). In Madrid, the average concentration of NO₂ in April 2020 was 11.7 micrograms per cubic meter of air (μg/m³). This was a reduction of over 55 percent compared to NO₂ levels in April 2019. Cities such as Rome and London saw similar reductions during this period.

Average monthly concentrations of nitrogen dioxide (NO₂) pollution in select cities in Europe from January 2019 to September 2023 (in micrograms per cubic meter of air)

Characteristic	Rome	Paris	Madrid	Stuttgart	London
Sep 2023	24.2	29.5	27.2	-	29.2
Aug 2023	19.7	18.5	18.6	20.3	16.8
Jul 2023	21.4	17.3	20.1	23.4	14.8
Jun 2023	23.1	23.2	20.4	25.6	18.8
May 2023	25	20	16.4	25	18
Apr 2023	24.9	24.7	22.1	25.6	21.8
Mar 2023	30.9	25.3	26.8	28.4	22.2
Feb 2023	42.7	36.6	37.8	33.3	31.3
Jan 2023	34.3	26.6	33.5	25.9	29.7
Dec 2022	39.4	30.2	33.9	32.7	31.2
Nov 2022	36	27.9	29.6	32.2	25
Oct 2022	35	30.5	36.4	29.2	24.1
Sep 2022	26.1	29.1	21.9	27.6	23
Aug 2022	19.6	23.5	19.3	27.4	19.4
Jul 2022	21.7	23.1	20.6	26.1	18.5
Jun 2022	25.2	24.8	18.5	25	18
May 2022	28.5	24.8	19.2	28.6	19.4
Apr 2022	27.5	27.9	20.1	29.3	18.5
Mar 2022	34.6	39.9	24.9	44.3	18
Feb 2022	34.6	31	41	28.8	20.1
Jan 2022	37.4	36.4	45.4	32.3	23.9
Dec 2021	42	33.9	37.2	32.9	32.9
Nov 2021	33.8	38.3	36.3	33.7	22.3
Oct 2021	31.9	35	36.9	34.9	37
Sep 2021	29.7	32	26.8	33.7	25.7
Aug 2021	20.9	18.9	20.2	26.1	28.5
Jul 2021	24	23.3	20.6	28.1	25.2
Jun 2021	25	25.4	18.9	30.4	25.4
May 2021	22.1	22.1	17.9	25.4	19.5
Apr 2021	27.9	28.4	21.7	33	22.1
Mar 2021	33.3	35.8	27.8	38.7	21.1
Feb 2021	41.3	32.3	29.1	41.7	22.9
Jan 2021	37.6	33.7	43	31.1	28
Dec 2020	40.1	29.8	28.9	33.7	28.4
Nov 2020	36.1	33.6	39.5	37.8	28.5
Oct 2020	34	26	28.6	33.3	29.9
Sep 2020	32.1	34.4	27	39.1	31.2
Aug 2020	21.6	25.1	21.5	33.4	31.4
Jul 2020	25.7	20.6	19.4	31.9	23.6
Jun 2020	23.2	23.4	15.4	28.7	25.6
May 2020	19.8	21.2	12.7	29	21.8
Apr 2020	17.9	21.1	11.7	30.7	17.5
Mar 2020	25.4	26.6	22	32.9	20.3
Feb 2020	45.1	28.1	43.9	38.9	19.8
Jan 2020	57.9	37.6	45.8	45.2	15.6
Dec 2019	45.6	37.5	39.4	43.2	36.6
Nov 2019	40.2	35.9	26	39.2	40.9
Oct 2019	43.4	30.7	40.3	37.8	33.5
Sep 2019	35	28.8	30.9	36.3	28.4
Aug 2019	26.8	28.3	25.1	38.1	25.4
Jul 2019	32.1	29.8	24.9	40.1	26.4
Jun 2019	35.8	30.4	23.2	39.1	25.9
May 2019	31.7	33.1	21.7	36.8	30.9
Apr 2019	39.4	39.7	26.4	39.9	38.9
Mar 2019	42.1	37.1	35.5	42.6	33.8
Feb 2019	46.9	54.5	54.8	61.1	47.3
Jan 2019	47.8	41.9	54	45	45.5