Many friends report an astounding improvement in air quality across the country over the past few weeks, an unexpected silver lining to coronavirus lockdown. They can breathe better and see distant mountains previously obscured by haze. The Washington Post, The Guardian, and NPR have covered the phenomenon. “Anyone walking, biking or driving outdoors can see the blue skies,” says The Mercury News. They were unclear as to whether the blue skies could be seen by those confined with only window views.
AirNow, developed by the EPA, makes its archives available online. Here is what the first Monday in April has looked like for the previous five years. 2020 is at the bottom.