Extreme rainfall events: evaluation with different instruments and measurement reliability

With regard to extreme events, it is known that an intensity of about 1 mm/min already represents an extreme intensity. Under alpine conditions, a precipitation event with intensity about 3 mm/min has occurred. Therefore the rain gauges in this region have to be able to measure in this and even in higher intensity ranges. This study deals with basically automated Tipping Bucket Rain (TBR) gauge, and Bulk precipitation samplers, which allows to hold back more than 95% of the cumulative rainfall that are verified within the space of the week without losses during the extreme events and with a minimum evaporation loss. In the last 10 years analysed, for a total of 221 extreme events, in 110 extreme events the Bulk samplers have collected rainfall more than automated TBR. In 17 extreme events an underestimation more than 10% was evaluated. The objective was to single out the counting errors associated with TBR gauge, during extreme events, so as to help the understanding of the measured differences between instruments in the field. We want to prove if the automated precipitation gauge, is or not, a reliable and precise device of measurements precipitation with particular interest regarding heavy and extreme events.