KQED Science had an interesting article this week about how historical paintings from the past can shed light on the amount of pollutants (both natural pollutants like volcanic particulates and human-injected pollutants from industry and transportation) in the atmosphere and how they change the way the sky looks.  I’ve talked about this in the past, but some new insights show that even in years with no volcanic eruptions, you can still see changes in how the sky is portrayed due to trends in pollution. You can read it at https://ww2.kqed.org/science/2014/06/03/famous-sunset-paintings-reflect-key-air-pollution-events-from-the-past/.

Source: Peter Lowenstein/EarthSky