Flood prediction remains one of the central challenges in hydrology, due to the intrinsic complexity of the processes governing runoff generation and their strong dependence on climate, soil, and geomorphological conditions. The body of research presented here develops a coherent framework aimed at bridging process understanding and probabilistic modelling, with a particular focus on theoretically derived flood frequency distributions.
From Conceptual Understanding to Theoretical Modelling
Early contributions (e.g., Gioia et al., 2007; Fiorentino et al., 2006) focused on identifying the key variables controlling flood generation, highlighting the role of runoff contributing areas, soil moisture, and rainfall variability as fundamental drivers of flood peaks.
A major step forward was the development of theoretically derived flood frequency distributions, based on the concept that flood peaks can be described as the product of runoff per unit area and the dynamically varying contributing area. This approach, initially formalized in the IF model and later extended, provides a physically-based alternative to purely statistical methods.
The work by Gioia et al. (2008) introduced a generalized framework incorporating multiple runoff generation mechanisms, showing that flood distributions can be interpreted through the coexistence of different threshold processes.
Dual Mechanisms and the TCIF Model
A key advancement of this research line is the recognition that flood generation is governed by two distinct mechanisms:
- ordinary events associated with limited contributing areas and infiltration excess
- extreme events associated with widespread basin saturation and storage exceedance
This conceptualization led to the development of the TCIF (Two-Component IF) model, which explicitly accounts for these dual processes.
The TCIF model (Gioia et al., 2012; Iacobellis et al., 2011) demonstrated how the interaction between climatic forcing and basin properties controls not only the magnitude of floods but also the shape and skewness of flood frequency distributions .
Moreover, regional applications showed that model parameters can be related to geomorphoclimatic descriptors, enabling prediction in ungauged basins and supporting regionalization approaches.
This page is part of the Hydrological Modelling research line of HydroLAB. See also: Hydrological Rainfall Extremes · Stochastic Modeling and Flood Dynamics · Ecohydrology · DREAM Model · Nature-Based Solutions.
Publications on this topic
- Manfreda, S., The space-time representation of extraordinary rainfall events., Ecohydrology, 2024. [pdf] [doi]
- Perrini, P., L. Cea, F. Chiaravalloti, S. Gabriele, S. Manfreda, M. Fiorentino, A. Gioia and V. Iacobellis, A Runoff-On-Grid approach to embed hydrological processes in shallow water models., Water Resources Research, 2024. [pdf] [doi]
- Pizarro, A., P. Dimitriadis, T. Iliopoulou, S. Manfreda and D. Koutsoyiannis, Stochastic analysis of the marginal and dependence structure of streamflows: From fine-scale records to multi-centennial paleoclimatic reconstructions., Hydrology, 2022. [doi]
- Manfreda, S., D. Miglino and C. Albertini, Impact of detention dams on the probability distribution of floods., Hydrology and Earth System Sciences, 2021. [doi]
- Manfreda, S., V. Iacobellis, A. Gioia, M. Fiorentino and K. Kochanek, Impact of climate on hydrological extremes., Water, 2018. [doi]
- Gioia, A., S. Manfreda, V. Iacobellis and M. Fiorentino, Comparison of different methods describing the peak runoff contributing areas during floods., Hydrological Processes, 2017. [pdf] [doi]
- Gioia, A., S. Manfreda, V. Iacobellis and M. Fiorentino, Performance of a theoretical model for the description of the water balance and runoff dynamics in Southern Italy., Journal of Hydrologic Engineering, 2014. [doi]
- Gioia, A., V. Iacobellis, S. Manfreda and M. Fiorentino, Influence of infiltration and soil storage capacity on the skewness of the annual maximum flood peaks in a theoretically derived distribution., Hydrology and Earth System Sciences, 2012. [doi]
- Iacobellis, V., A. Gioia, S. Manfreda and M. Fiorentino, Flood quantiles estimation based on theoretically derived distributions: regional analysis in Southern Italy., Natural Hazards and Earth System Sciences, 2011. [doi]
- Fiorentino, M., A. Gioia, V. Iacobellis and S. Manfreda, Regional analysis of runoff thresholds behaviour in Southern Italy based on theoretically derived distributions., Advances in Geosciences, 2011. [pdf] [doi]
- Iacobellis, V., M. Fiorentino, A. Gioia and S. Manfreda, Best Fit and Selection of Theoretical Flood Frequency Distributions Based on Different Runoff Generation Mechanisms., Water, 2010. [pdf] [doi]
- Carone, M. T., T. Simoniello, S. Manfreda and G. Caricato, Watershed influence on fluvial ecosystems: an integrated methodology for river water quality management., Environmental Monitoring and Assessment, 2009. [pdf] [doi]
- Manfreda, S., Runoff Generation Dynamics within a Humid River Basin., Natural Hazards and Earth System Sciences, 2008. [doi]
- Manfreda, S. and M. Fiorentino, A Stochastic Approach for the Description of the Water Balance Dynamics in a River Basin., Hydrology and Earth System Sciences, 2008. [doi]
- Gioia, A., V. Iacobellis, S. Manfreda and M. Fiorentino, Runoff thresholds in derived flood frequency distributions., Hydrology and Earth System Sciences, 2008. [doi]
- Fiorentino, M., S. Manfreda and V. Iacobellis, Peak Runoff Contributing Area as Hydrological Signature of the Probability Distribution of Floods., Advances in Water Resources, 2007. [doi]
- Fiorentino, M., A. Gioia, V. Iacobellis and S. Manfreda, Analysis on flood generation processes by means of a continuous simulation model., Advances in Geosciences, 2006. [pdf] [doi]
- Manfreda, S., M. Fiorentino and V. Iacobellis, DREAM: a Distributed model for Runoff, Evapotranspiration, and Antecedent Soil Moisture Simulation., Advances in Geosciences, 2005. [doi]