In France, there has been an unusual high aerosol rate in cities early this spring when temperatures rose above the seasonal average. Cars and trucks had to reduce speed, public transportations were free for a couple of days and we got alternate traffic circulation. I, as well as authorities, used to think that atmospheric aerosol came mainly from vehicules exhausts, but in terms of proportions, it seems that manufacturing industry comes first, followed by agriculture and then by residential/tertiary (how about turning that off for a couple of days?). It is probably be useless, as this animated map shows very well, to slow down or even stop activities at a local scale. Dusts and atmospheric aerosol get carried away on very long distances and remain at high altitudes for weeks before they drop. Stating that Earth is a global mecanism and that regional and national borders are not relevant to global pollution regulation might sound as a cliché, but maybe we need more NASA video on TV news instead of fighting about the fairness of alternate traffic for truck drivers.
Red particle is mostly Sahara red sand that can reach an altitude of four to five kilometers and get carried away on thousands of kilometers. Blue flows are made of sea spray (basically sea salt pushed by jet streams). Green is from wildfire (mostly in South America, central Africa and south east Asia, in between the rainforest latitudes). White is fossil fuel combustion result, mostly visible above industrial and urbanized areas. Those particles are also released by volcanoes.