On the 23 March 2020, a country-wide COVID-19 lockdown was imposed on the UK. The following 100 days saw anthropogenic movements quickly halt, before slowly easing back to a “new” normality. In this short communication, we use data from official UK air-quality sensors (DEFRA AURN) and the UK Met Office stations to show how lockdown measures affected air quality in the UK. We compare the 100 days post-lockdown (23 March to 30 June 2020) with the same period from the previous 7 years. We find, as shown in numerous studies of other countries, the nitrogen oxides levels across the country dropped substantially (∼ 50%). However, we also find the ozone levels increased (∼ 10%), and the levels of sulphur dioxide more than doubled across the country. These changes, driven by a complex balance in the air chemistry near the surface, may reflect the influence of low humidity as suggested by Met Office data, and potentially, the reduction of nitrogen oxides and their interactions with multiple pollutants.

中文翻译：

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英国 COVID-19 封锁：减少空气污染 100 天？

2020 年 3 月 23 日，英国在全国范围内实施了 COVID-19 封锁。在接下来的 100 天里，人类活动迅速停止，然后慢慢恢复到“新”常态。在这个简短的交流中，我们使用来自英国官方空气质量传感器 (DEFRA AURN) 和英国气象局站的数据来展示封锁措施如何影响英国的空气质量。我们将封锁后的 100 天（2020 年 3 月 23 日至 6 月 30 日）与前 7 年的同期进行比较。我们发现，正如其他国家的大量研究所示，全国的氮氧化物水平大幅下降（~50%）。然而，我们也发现臭氧水平增加了（~ 10%），全国的二氧化硫水平增加了一倍以上。这些变化是由地表附近空气化学的复杂平衡驱动的，