ABSTRACT
Climate change and the modification of urban environment increase the frequency
and the impact of flooding rising the interest of researchers and practitioners on
this topic. Usually flooding frequency analysis in urban areas are indirectly carried
out by adopting advanced hydraulic models to simulate long historical rainfall
series or design storms. However their results are affected by a grade of uncertainty
which has been much investigated in recent years. One of the most critical source
of uncertainty inherent to hydraulic model results is linked to the imperfect
knowledge of the rainfall input data both in time and space. Several studies show
that hydrological modelling in urban area needs that rainfall data have fine
resolution in time and space. The present study aims to analyse the effect of the
resolution of rainfall input both in space and in time. The analysis used flooding
depths and damage as references to assess the impact of rainfall knowledge on
urban flooding modelling results. To this aims, with regard to a case study, the
maximum efficiency conditions for the model and the uncertainty affecting urban
flooding modelling results were evaluated by the means of GLUE analysis and the
added value provided by the adoption of finer temporal and spatial resolutions were
assessed
