A non arbitrary definition of rain event: the case of stratiform rain

Abstract

A long standing issue in Hydrology is the arbitrariness of the rain "event" definition. In this manuscript, we show that 1) the event definition resting on the occurrence of a minimum rainless period and the one resting a sequence of consecutive wet intervals are statistically equivalent. 2) In the case of stratiform rain, a non arbitrary definition of rain event is possible. The dynamical properties of stratiform rain indicate the range [1.5,4] h as the proper one for the choice of a minimum rainless period for Chilbolton, UK. 3) The intra event dynamical variability is "described" by an alternate sequence of quiescent and active phases.