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Title: Propagation of radar rainfall uncertainties into urban pluvial flood modeling during the North American monsoon
Pluvial flooding in urban regions is a natural hazard that has been rarely investigated. Here, we evaluate the utility of three radar (Stage IV, MRMS, and GCMRMS) quantitative precipitation estimates (QPEs) and the SWMM hydrologic-hydraulic model to simulate pluvial flooding during the North American Monsoon in Phoenix. We focus on an urban catchment of 2.38 km2 and, for four storms, we simulate a set of flooding metrics using the original QPEs and an ensemble of 100 QPEs characterizing radar uncertainty through a statistical error model. We find that Stage IV QPEs are the most accurate, while MRMS QPEs are positively biased and their utility to simulate flooding increases with the gage correction done for GCMRMS. For all radar products, simulated flood metrics have lower uncertainty than QPEs as a result of rainfall-runoff transformation. By relying on extensive precipitation and basin datasets, this work provides useful insights for urban flood predictions.  more » « less
Award ID(s):
1831475 1735040
PAR ID:
10295842
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Hydrological Sciences Journal
ISSN:
0262-6667
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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