I manually outlined 14,974 individual dust storm instances over 8 Mars years of Mars Daily Global Maps and organized these instances into 228 sequences. The data are posted online on the Harvard Dataverse. The dataset lists latitude, longitude, time, and storm area for each instance.
An example of a dust storm “sequence” is shown below. Each panel is a single sol on Mars. The enclosed areas are individual dust storm instances. The sequence (an organized collection of storms) is in blue; other dust instances are in gold.
MDAD allows for the examination of interesting questions. Here is the average duration that a given point remains dusty after a storm starts (top) and how long do someone on the surface would have to wait (on average) between dust storms (bottom). The midlatitudes are quite dusty, near to the equator, the interval between storms jumps by a considerable amount. MSL in Gale Crater (5°S, 137°E) has a >60 sol interval between storms. Perseverance in Jezero Crater (18°N, 77°E) should have a more interesting time, only ~40 sols between dust storms.
To give an idea of how big the dataset is, the figure below shows the spatial distribution of dust storm instances in a sequence (an organized collection of storms, top panel) versus unorganized activity (bottom panel). Most activity is confined between 30°–60°N/S in the winter storm tracks, but some storms flush across hemispheres.
The temporal distribution of sequences shown below is variable in size and exact timing each year, but unorganized activity (black) regularly follows the edge of the polar ice cap each year. We further categorize “Major” (gold above) and “Minor” (blue) sequences. Major sequences are larger than 10^7 km^2, flush from their origination region, and raise the zonal-mean opacity >0.3. They have unique precursor conditions so that they seem to be instigated by previous dust activity. The growth curves and histories of the major dust events are distinctively different from non-major sequences, so may have predictive capabilities.
The development of dust activity follows the progression of synoptic storms systems. The curved morphology of dust storms aligns with cold fronts, with cold, high pressure following afterwards (below).
Development of the MDAD is ongoing for Mars Years 33 and 34 (2015–2018), and machine learning techniques will be applied to help with storm identification and for comparison to Perseverance and Curiosity observations.