Overview of methods applied in creation of rainfall intensity-duration-frequency curves

The comparison represents the collected substantial information about methods related to creation of rainfall IDF curves (intensity-duration-frequency). Creation of IDF curves usually include two steps - primary and secondary processing. Primary processing is the process of choosing adequate high intensities of rainfall, of both short duration (less than 1 or 2 hours) and long durations (greater than 1 or 2 hours). Secondary processing is the process of determination of probabilities related to rainfall of specific durations and intensities, in order to obtain frequency characteristics (return periods), and later providing od IDF curves.

- data type - defines which data was used for creation of IDF curves
- data observation stations - defines the number of stations used in the research
- extreme values choice - usually annual maximums or peak over threshold
- primary processing of rainfall data - defines wether observed rainfall depths and durations were primary processed in order to obtain maximum intensities for each rainfall duration (usually 5, 10, 20, 30,...,1080, 1440 minutes), e.g., by sliding window approach with fixed duration. In some cases, intensities or depths for different durations are on disposition
- temporal downscaling - defines wether rainfall data of low resolution was downscaled (dissagregated) to obtain intensities or depths of lower rainfall durations
- spatial downscaling - defines wether intensity - duration - frequency curves were obtained by spatial downscaling, e.g., from climate models outputs or satellite observations or radar observations
- multivariate freqency analysis - defines wether intensity - duration - frequency curves were obtained by multivariate analysis or univariate analysis
- uncertainty estimation - defines wether confidence intervals for rainfall intensities (or depths), that is, for curves, were obtained