Rainfall intensity-duration patterns for flood occurrence in Attica region.

Abstract: Attica region suffers from heavy rainfall that triggers flood events causing significant damages, mainly in the urbanized areas. This analysis presents indicative thresholds regarding maximum rainfall intensity (I)-duration (D), which separate events in three categories: (i) events that are not associated with floods and usually correspond to low intensities, (ii) events that are linked to the highest intensities and thus with flood occurrence, and (iii) events experience a range of intensities that correspond to mixed conditions concerning flood occurrence. The analysis is performed using the available precipitation records from 14 stations located in the Attica region (Central Greece) for the period 2005-2016. A dataset regarding Fire Service operations in flooded properties in the area during the same period is also used in order to classify each event as flood-related or not, in case flooded properties recorded or not, respectively. The I-D thresholds are expressed using power low equations that describe two limits: the first one (‘lower limit’) defines the area below which floods are absent and above which flood occur or not, while the second (‘upper limit’) defines the minimum limit of maximum intensities above which only events linked to flooding are observed. The corresponding equations are determined per station with the aim to cover a significant part of t region, however the reliability of the estimated thresholds is affected by the spatial distribution and the varying length of records.     «

Abstract: Attica region suffers from heavy rainfall that triggers flood events causing significant damages, mainly in the urbanized areas. This analysis presents indicative thresholds regarding maximum rainfall intensity (I)-duration (D), which separate events in three categories: (i) events that are not associated with floods and usually correspond to low intensities, (ii) events that are linked to the highest intensities and thus with flood occurrence, and (iii) events experience a range of i...     »