Intensity-Duration-Frequency curves at the global scale


Intensity-Duration-Frequency (IDF) curves usefully quantify extreme precipitation. Unfortunately, sparse, infre-quent or short observations hinder the creation of robust IDF curves in many locations around the world. We present a global, multi-temporal (1 to 360 h) dataset of GEV parameters at 30 km resolution named PXR-2(Parametrized eXtreme Rain). Using these data we show that the two GEV parameters typically scale robustlywith event duration (r2>0.85, p<0.01). Thus, we propose a four-parameter IDF formula that allows estimates ofrainfall intensity for a continuous range of durations, and describe the PXR-4 dataset that compiles these parame-ters. This parameter scaling property opens the door to estimating sub-daily IDF from daily records. We evaluatethis characteristic for selected global cities and a rain gauge network in the United Kingdom. PXR aims to be of im-mediate use for engineers for designing critical infrastructure such as urban drainage systems, dams and highways,with potential applications in other fields of earth sciences.

Vienna, Austria