Articles | Volume 21, issue 12
Research article
18 Dec 2017
Research article |  | 18 Dec 2017

Does nonstationarity in rainfall require nonstationary intensity–duration–frequency curves?

Poulomi Ganguli and Paulin Coulibaly

Data sets

Annual maximum rainfall data EC (Environment Canada)

Hourly (HLY) and daily (DLY) rainfall data ECCC (Environment and Climate Change Canada) ftp://client_climate@ Documentation.pdf

2011 census data and census digital boundary shape files Statistics Canada

Short summary
Using statistical models, we test whether nonstationary versus stationary models show any significant differences in terms of design storm intensity at different durations across Southern Ontario. We find that detectable nonstationarity in rainfall extremes does not necessarily lead to significant differences in design storm intensity, especially for shorter return periods. An update of 2–44 % is required in current design standards to mitigate the risk of storm-induced urban flooding.