is a major component of particulate matter globally. Most sand and dust storms originate from a dust belt stretching from north Africa through the Middle East into Asia. Dust storms can also arise in arid areas of North and South America and Australia. Particles from dust storms can remain in the atmosphere and travel thousands of km from their source.

Mineral dust is a complex mixture that can be formed from quartz, feldspars, clays, calcites, iron oxides and other material blown from the Earth's crust.