U8be2 U73ed U8be2 U7279 U4ef7 U6253 U6298 U660e U73e0 U4f1a U5458 U670d U52a1 U7b49 U7279 U4ef7... Tiger Zhao, Wuhan Shi, Hubei Sheng, China

Ambient pollution is a byproduct of economic activity. It has been widely reported that COVID-19 and associated lockdowns have generated large improvements in air quality worldwide, including to China's notoriously-poor air quality. We analyze China's official pollution monitor data and account for the large, recurrent improvement in air quality following Lunar New Year (LNY), which essentially coincided with lockdowns in 2020. With the important exception of NO2, China's air quality improvements in 2020 are smaller than we should expect near the pandemic's epicenter: Hubei province. Compared with LNY improvements experienced in 2018 and 2019 in Hubei, we see smaller improvements in SO2 while ozone concentrations increased in both relative and absolute terms (roughly doubling). Similar patterns are found for the six provinces neighboring Hubei. We conclude that whether COVID-19 actually decreased pollution in China depends on the pollutant and reference period considered.

The initial epicentre of the coronavirus outbreak will lower its emergency response level from tomorrow. These are the key coronavirus developments from Friday.

An, Jin, 1978 December-