This map shows the aerosol optical thickness of three aerosols over time, these aerosols are black carbon, dust, and sea salt. Move through these slides for more information on each one or scroll down to open the map.

Produced by combustion processes such as forest fires (~42%), diesel engines (~24%), and other human sources. It is a major contributor to air pollution, and is estimated to cause hundreds of thousands of deaths a year.[1]

Atmospheric dust comes from wind picking up small particles in hyper-arid regions like deserts, especially in northern Africa and the Middle East.

Atmospheric sea salt comes from sea spray and is mostly made up of sodium chloride. Sea salt particles hugely vary in size from about 0.05μm to 10μm.