It is, you can probably check the plots from your local air pollution measurements. (Of course, in isolation that means nothing since the values are influenced

It is, you can probably check the plots from your local air pollution measurements. (Of course, in isolation that means nothing since the values are influenced heavily by weather, eg wind direction, but in aggregate and in comparison to the past you can interpret it.) It is also especially obvious in satellite images (for those pollutants that can easily measured by satellite). Eg. the NO2 concentrations have gone down significantly in many areas of the world. eg. https://www.space.com/nasa-satellite-air-pollution-us-northeast-coronavirus.html https://www.space.com/nasa-satellite-air-pollution-us-northe... but you can easily look for more.