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In some rainfall-triggered landslides, intensity-duration thresholds can have limited prediction ability; therefore, investigation of alternative approaches that can be used for temporal prediction of rainfall-induced landslides is needed. This paper presents a methodology for predicting rainfall-induced shallow landslides based on a lumped conceptual hydrological model. The production storage level during the rainfall event and the rainfall sum during the event are used for landslide prediction. Based on these two hydro-meteorological variables a threshold is defined that could be used for rainfall-induced landslides prediction as part of an early warning system. The presented methodology is tested using the meso-scale Selška Sora River catchment case study in western Slovenia where 20 active landslides from the Slovenian National Landslide Database are used to calibrate and evaluate the methodology performance. The results are compared to three different (i.e. local, regional, and global) intensity-duration thresholds. The results of the presented approach are superior in terms of several goodness-of-fit criteria compared to tested local and global ID thresholds. Because only daily rainfall, evapotranspiration, and discharge data are needed to calibrate the selected hydrological model and only daily rainfall and evapotranspiration to run the model, the presented approach could also be useful for data-scarce areas where detailed physically based landslide prediction models that require many data cannot be constructed. Moreover, we have also derived the probabilistic version of the proposed threshold for triggering of shallow landslides using copula functions. [ABSTRACT FROM AUTHOR]

Summary: Rainfall kinetic energy–intensity relationships for rainfall erosivity estimation were established on the basis of raindrop size distribution measurements performed in the Brkini hilly area in southwest Slovenia, a transitional area between the Mediterranean and continental climate conditions. A set of measurement instruments, an optical disdrometer coupled with a rain gauge, was installed on two locations: Koseze and Kozjane. The data set contained raindrop size distribution and rainfall intensity measurements of the rainfall events that occurred during a one-year period in the 2008/2009 season. The rainfall intensities obtained with the rain gauges were used for event rainfall depth control measured by the disdrometers and testing the established kinetic energy–intensity (KE–I) relationships. Two exponential KE–I relationships were established for each measuring site, for 1-min and 5-min rainfall intensity data, respectively. Their performances were tested and compared with the performances of other KE–I relationships proposed by authors throughout the world, which could be recognised as relatively suitable for kinetic energy estimation in the Mediterranean area. The comparison included 11 KE–I relationships expressed with linear, linear-log or exponential formulations. The analyses exposed the rainfall intensity overestimation by the disdrometers and the limited use of the tipping bucket rain gauge for kinetic energy estimation under such climate conditions. According to our results, the established KE–I relationship for 5-min intensity data in Koseze is recommended to be used while estimating rainfall kinetic energy in the Mediterranean part of Slovenia. As input data, rainfall intensities measured with precise weighing rain gauges, as those installed in the Slovenian meteorological network, should be used. However, when using rainfall intensity data obtained with a tipping bucket rain gauge of lower accuracy or insufficient intensity range, the exponential relationship of is expected to deliver better kinetic energy estimations. [Copyright &y& Elsevier]