Helen Worden in Physics Today

“We have seen a decrease in air pollution on short time frames,” says atmospheric scientist Helen Worden of the National Center for Atmospheric Research in Boulder, Colorado.  In one unpublished result since the pandemic began, Worden and colleagues found that, in a corridor between Wuhan and Beijing, peak values of CO were down by 30–45% following Chinese New Year this year compared with the same period in 2019. Atmospheric concentrations of particulate matter, aerosols, and many molecular species that contribute to global warming and poor air quality have plunged nearly everywhere.