This study expands the Metastatistical Extreme Value (MEV) framework to sub-daily rainfall frequency analysis and compares it to extreme value theory methods in presence of short records and measurement errors. Ordinary events are identified based on the temporal autocorrelation of hourly data and modeled with a Weibull distribution. MEV is compared to extreme value theory methods in the estimation of long return period quantiles from actual data (160 rain gauges with at least 60-year record in the contiguous United States) and on synthetic data perturbed with measurement errors typical of remote sensing rainfall estimation. MEV tends to underestimate the 100-year return period quantiles of hourly rainfall when 5–20 years of actual data are used, but presents diminished uncertainty. When a good model of the ordinary events and adequate number of events per year are available, MEV is able to provide information on the 100-year return period quantiles from 10–20, or even 5 years of data with significantly reduced uncertainty (<30% uncertainty for 5-year records). MEV estimates of 100-year return period quantiles from short records are much less sensitive than extreme value theory methods to additive/multiplicative errors, presence of cap values in the estimates, and missing of extreme values. Results from this study strongly support the use of MEV for rainfall frequency analyses based on remotely sensed datasets.
Bibliographical noteFunding Information:
The study was partially funded by the Lady Davis Fellowship Trust [project: RainFreq], by the Israel Science Foundation [grant no. 1007/15 ], and by NSF-BSF grant [ BSF 2016953 ]. Efthymios Nikolopoulos and Emmanouil Anagnostou were supported by Eversource Energy Center at the University of Connecticut. The authors acknowledge Davide Zoccatelli for the helpful discussions.
© 2018 Elsevier Ltd
- Dependence on data record and measurement errors
- Long return period quantile estimation uncertainty
- Metastatistical extreme value
- Short records
- Sub-daily rainfall frequency