The Cloudspotting on Mars Citizen Science Project: Seasonal and spatial cloud distributions observed by the Mars Climate Sounder

As tracers of the major volatile cycles of Mars — CO2, H2O, and dust — clouds are important for understanding the circulation of the martian atmosphere and hence martian climate. We present the spatial and seasonal distribution of laterally-confined clouds in the middle atmosphere of Mars during one Mars Year as identified in limb radiance measurements by the Mars Climate Sounder. Cloud identifications were made by citizen scientists through the “Cloudspotting on Mars” citizen science project, hosted on the citizen science platform Zooniverse. A method to aggregate the crowdsourced data using a novel clustering algorithm is developed. The derived cloud catalog is presented and the seasonal and spatial distribution of clouds is discussed in terms of key populations.