Hydroclimatic Fluctuations and Patterns of River Flow Regimes
Event details
| Date | 19.11.2013 |
| Hour | 16:15 › 17:15 |
| Speaker | Dr Gianluca Botter, Hydrology Laboratory, Department of Civil, Environmental and Architectural Engineering, University of Padova (IT) |
| Location | |
| Category | Conferences - Seminars |
Abstract:
River flow regimes identify the streamflow variability at different temporal scales, from daily to decadal. Streamflow regimes not only constrain anthropogenic uses of fresh water, such as hydropower and irrigation, but also shape form and function of riverine ecosystems. Landscape and climate alterations in the Anthropocene threaten global-scale shifts of river flow regimes, with potentially dramatic ecologic and socioeconomic consequences. Nevertheless, a theory that identifies the range of foreseen impacts on streamflows resulting from inhomogeneous forcings and sensitivity gradients across diverse regimes is still lacking. In this contribution, a dimensionless index embedding simple climate and landscape attributes (the ratio of the mean interarrival of streamflow-producing rainfall events and the mean catchment response time) is used to identify the nature of flow regimes and their sensitivity to changes of the external forcing. The proposed index is based on a mechanistic analytical model in which streamflow dynamics are driven by stochastic rainfall, and discriminates erratic regimes with enhanced intra-seasonal streamflow variability from persistent regimes endowed with reduced discharge variability. The proposed classification is successfully applied to 110 seasonal streamflow distributions observed in diverse unregulated catchments of the Alps and the United States, allowing the identification of dominant patterns of catchment response across geomorphoclimatic gradients. The impact of multi-scale fluctuations of climate drivers (temperature, precipitation) on the streamflow distributions is also assessed within the same framework. Theoretical and empirical data show that erratic regimes, typical of rivers with low mean discharges, are more resilient than persistent regimes, owing to their reduced sensitivity to variations of the external forcing. The proposed classification of flow regimes provides a new framework for characterizing the functioning of freshwater ecosystems (in particular stream vegetation and food-web dynamics) and eventually contributes to evaluate the alteration produced by water infrastructures and the effectiveness of water management strategies in times of global change.
Dr Gianluca Botter holds a degree in Environmental Engineering and a Ph.D in Environmental Modeling from the University of Padova, where he’s currently assistant professor of hydrology and water resources management. He’s author and co-author of more than 35 papers in peer-reviewed journals, including PNAS, PlosONE and Geophysical Research Letters (h-index = 15). In 2010 he has been awarded with the Torricelli prize as leading under-34 researcher in the fields of Hydraulics and Hydrology, while in 2011 he received the Outstanding Referee Award for Water Resources Research from the American Geophysical Union. He’s member of the Editorial Board of Advances in Water Resources, and reviewer for several multidisciplinary, geophysics and hydrology journals. His scientific interests include the characterization of river flow regimes and the analysis of water quality patterns in space and time, with particular emphasis on the effects of anthropogenic activities and climate change on freshwaters.
River flow regimes identify the streamflow variability at different temporal scales, from daily to decadal. Streamflow regimes not only constrain anthropogenic uses of fresh water, such as hydropower and irrigation, but also shape form and function of riverine ecosystems. Landscape and climate alterations in the Anthropocene threaten global-scale shifts of river flow regimes, with potentially dramatic ecologic and socioeconomic consequences. Nevertheless, a theory that identifies the range of foreseen impacts on streamflows resulting from inhomogeneous forcings and sensitivity gradients across diverse regimes is still lacking. In this contribution, a dimensionless index embedding simple climate and landscape attributes (the ratio of the mean interarrival of streamflow-producing rainfall events and the mean catchment response time) is used to identify the nature of flow regimes and their sensitivity to changes of the external forcing. The proposed index is based on a mechanistic analytical model in which streamflow dynamics are driven by stochastic rainfall, and discriminates erratic regimes with enhanced intra-seasonal streamflow variability from persistent regimes endowed with reduced discharge variability. The proposed classification is successfully applied to 110 seasonal streamflow distributions observed in diverse unregulated catchments of the Alps and the United States, allowing the identification of dominant patterns of catchment response across geomorphoclimatic gradients. The impact of multi-scale fluctuations of climate drivers (temperature, precipitation) on the streamflow distributions is also assessed within the same framework. Theoretical and empirical data show that erratic regimes, typical of rivers with low mean discharges, are more resilient than persistent regimes, owing to their reduced sensitivity to variations of the external forcing. The proposed classification of flow regimes provides a new framework for characterizing the functioning of freshwater ecosystems (in particular stream vegetation and food-web dynamics) and eventually contributes to evaluate the alteration produced by water infrastructures and the effectiveness of water management strategies in times of global change.
Dr Gianluca Botter holds a degree in Environmental Engineering and a Ph.D in Environmental Modeling from the University of Padova, where he’s currently assistant professor of hydrology and water resources management. He’s author and co-author of more than 35 papers in peer-reviewed journals, including PNAS, PlosONE and Geophysical Research Letters (h-index = 15). In 2010 he has been awarded with the Torricelli prize as leading under-34 researcher in the fields of Hydraulics and Hydrology, while in 2011 he received the Outstanding Referee Award for Water Resources Research from the American Geophysical Union. He’s member of the Editorial Board of Advances in Water Resources, and reviewer for several multidisciplinary, geophysics and hydrology journals. His scientific interests include the characterization of river flow regimes and the analysis of water quality patterns in space and time, with particular emphasis on the effects of anthropogenic activities and climate change on freshwaters.
Practical information
- General public
- Free
- This event is internal
Organizer
- EESS - IIE
Contact
- Prof. Andrea Rinaldo, IIE