Images from instruments on Cassini as well as from telescopes on the groundreveal the presence of sporadic small-scale cloud activity in the coldlate-winter north polar of Saturn's large moon Titan. These clouds lieunderneath the previously discovered uniform polar cloud attributed to aquiescent ethane cloud at ~40 km and appear confined to the same latitudes asthose of the largest known hydrocarbon lakes at the north pole of Titan. Thephysical properties of these clouds suggest that they are due to methaneconvection and condensation. Such convection has not been predicted for thecold winter pole, but can be caused by a process in many ways analogous toterrestrial lake-effect clouds. The lakes on Titan are a key connection betweenthe surface and the meteorological cycle.
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