– Climate change and IDF (Intensity, Duration, Frequency) curves: An overview of science and guidelines for adaptation

One of the most important impacts of a warmer climate is the projected increase in the frequency of extreme rainfall. A review of the recent scientific literature paints a complex picture in which the amplification of extremes depends on a multitude of factors. While some precipitation indices may follow the Clausius-Clapeyron (C-C) scaling of ~7% per 1°C of warming, there is substantial evidence of a larger scaling (Super C-C) for daily extremes, and even more for sub-daily extremes. However, none of the current measures adopted by various governing bodies to adapt Intensity-Duration-Frequency (IDF) curves to the future climate recognize the likely Super C-C scaling of extreme rainfall. These implications are even more important for the short duration rainfall that generates the extreme runoff in cities and small rural catchments. This presentation will also discuss the remaining scientific gaps and will offer technical recommendations for practitioners on how to adapt IDF curves to improve climate resilience.

Research/Study carried out with the cooperation of: Jean-Luc Martel, Hydrology, Climate and Climate Change Laboratory, École de technologie supérieure / François P. Brissette, Hydrology, Climate and Climate Change Laboratory, École de technologie supérieure / Magali Troin, Hydrology, Climate and Climate Change Laboratory, École de technologie supérieure & HydroClimat | TVT, Maison du Numérique et de l’Innovation / Philippe Lucas-Picher, Groupe de Météorologie de Grande Échelle et Climat (GMGEC), Centre National de Recherches Météorologiques (CNRM), Université de Toulouse & Centre National de la Recherche Scientifique (CNRS), Météo-France / Richard Arsenault, Hydrology, Climate and Climate Change Laboratory, École de technologie supérieure.