Summary

Airborne dust is a critical part of the atmosphere and climate of Mars.The importance of dust in the Martian atmosphere has led to extensive study of how and why dust storms begin, grow, and eventually decay. Scientists use observations combined with laboratory and numerical modeling techniques to better understand dust storms on Mars.Observations show that there is always dust in Martian atmosphere but that there are some seasons that are dustier than others.There is generally a low-level background dust haze observed during the first half of the year (northern hemisphere spring and summer), and increased dustiness observed during the second half of the year (northern hemisphere autumn and winter).Dust storms and their associated hazes range in size from meters across (local-scale) to thousands of meters across (global-scale).The largest and most infrequent dust storms—global dust storms—significantly impact the temperature and wind structures in the atmosphere on a global scale.While scientists have made significant progress in characterizing the behavior and occurrence of dust storms on Mars, many open questions remain that require future observational, laboratory, and numerical modeling studies to answer.