Studies find global COVID-19 lockdowns have significantly reduced PM2.5 and NO2 pollution, but ozone up
Green Car Congress
MAY 12, 2020
For comparison, columns over the same time periods are shown for 2019. The week of Chinese New Year holiday is indicated by the red lantern shown inset panels (b) and (h). However, the study found nitrogen dioxide pollution did not decrease over Iran, one of the earliest and hardest-hit countries. van Gent, J., Eskes, H.,
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