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The pronounced weekly variation in the ash dispersal may result from the varying Eddies that pass by the region of the volcano. The Eddies are mesoscale (order of 1000 km), and thus which Eddy occupies the region during the eruption would serve as the main determinant of the ashes' dispersal. Moreover, the local variance has significant downstream effects.
In order to understand over what time periods the ash dispersal would vary, one must look into the time scales of the Eddys in the Icelandic region. Further simulations should explore variations in dispersal from daily changes to the eruption date.
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