Bucharest, the capital of Romania
- Analysed stations:
| B-6 (latitude: 44.44, longitude: 26.10, altitude: 79.00) | B-4 (latitude: 44.38, longitude: 26.13, altitude: 80.00) |
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- Nitrogen Dioxide (NO2) Analysis:
Throughout the whole analysed period, there is a general trend of decreasing NO2 emissions in 2020 compared to 2019 in the B-6 station area (Calea Victoriei-a very crowded area in the centre of Bucharest). The decrease is clear during the state of emergency (March 16-May 14) where, with few exceptions, the amount of NO2 is much lower in 2020 (20-40 μg / m³) compared to 2019 (50-80 μg / m³). The lowest values of NO2 emissions were recorded during the state of emergency, then followed an increase simultaneously with the relaxation of restrictions, variations in sawtooth and a new period with sustained low emissions between November 18 and December 6, probably influenced by the lockdown in surrounding towns from Ilfov county.
- Carbon Monoxide (CO) Analysis:
In the B-6 station area, the amount of CO was lower in 2020 than in 2019. The chart shows that at the beginning of 2020, in January, there were very high values of CO emissions (exceeding the values in 2019), but from February, when the first COVID-19 cases appeared, the emissions started to decrease, then remained at low values until the end of the year.
- Sulfur Dioxide (SO2) Analysis:
As for the SO2 emissions recorded at station B-4 (Berceni-close to the entrance in Ilfov county; at station B-6 the amount of SO2 is not measured), the quantities of SO2 in 2020 were generally very close to those in 2019. The only period when the emissions in 2019 were significantly lower than in 2019 was October 30-November 19 when the incidence rate of COVID-19 cases exceeded 3 per thousand in Bucharest, schools were in the red scenario, and quarantine began in surrounding towns from Ilfov county.
- Conclusion:
Therefore, the ground measurements revealed that the COVID-19 pandemic, lockdown and other imposed restrictions caused a clear decrease of atmospheric pollution in Bucharest, the capital of Romania, where air pollution is normally a real concern.
Ilfov County
- Analysed station:
| B-7 (latitude: 44.35 , longitude: 26.03 , altitude: 80.00 ) |
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- Nitrogen Dioxide (NO2) Analysis:
Throughout the whole year 2020 we can observe that the NO2 levels are extremely similar compared to 2019 in the B-7 station area in Ilfov. For some periods of time (January, March-April, June and December) there is a decrease in the NO2 quantity mainly caused by the imposed quarantine in Ilfov, but generally the NO2 emissions tend to stay unchanged.
- Carbon Monoxide (CO) Analysis:
Unfortunately, CO emissions are not measured in any of the stations in Ilfov county yet.
- Sulfur Dioxide (SO2) Analysis:
Contrary to what we expected, the SO2 levels in quarantine increased, as the chart shows. In the beginning of the analyzed period, the SO2 emissions don’t change until April (when quarantine was installed), when the SO2 levels grow. Then in the next few months, the SO2 emissions return to the same level as in 2019, followed by an unexpected raise in November, when we can notice the visibly higher quantity. That happened because of the short relaxation of restrictions. After that, the charts report a sudden drop on November 20th in the SO2 levels caused by the re-installation of quarantine. There is a general trend of growth in the SO2 emissions in 2020.
- Conclusion:
The COVID-19 pandemic and quarantine in Ilfov didn’t bring the expected decrease in pollution, as the ground measurements don’t show a lowering trend in the levels of NO2 and SO2, but an unchanging quantity of NO2 with small decreases and a slightly increasing quantity of SO2.