Marco Borga

University of Padova, Italy

Biography

Marco Borga, is an associate professor of hydrology at the University of Padova (Italy), where he teaches graduate courses of forest hydrology and hydraulics. He holds B.S. and M.S. degrees in civil engineering from the University of Padova. His research interests are in the areas of hydrology and geomorphology. In hydrology, his research interests are focused on flood hydrology and hydrometeorology, including water resources applications of weather radar and remote sensing, and hillslope hydrology. In geomorphology, the interests are on hydrological analysis of erosion processes and shallow landsliding. He served as a reviewer of the European Commission for FP 5 and 6, and is an associate editor of the Journal of Hydrology and of Journal of Flood Risk Management. He currently coordinates the EU FP6 project HYDRATE (Hydro-meteorological Data Resources and Technology for Effective Flash Flood Forecasting).

Abstract: Hydrologic hazards: The scales and social response to floods

The occurrence of floods is of concern in hydrologic and natural hazards science due to the top ranking of such events among natural disasters in terms of both number of people affected globally and damages. Among flood events, flash floods are characterized by relatively small spatial and temporal scales of occurrence which emphasize the relevant hazard and the vulnerability of communities exposed to these events. Several important consequences arise in term of risk management strategies from the characterisation of flash flood hazard scales. Because the elements at risks are highly dispersed, the management of the flash flood risk by means of structural measures is difficult and often unsustainable in ecological or economic terms. Flash flood forecasting, warning and emergency management are, by their nature, suitable to cope with the residual risk. However, specific difficulties with flash flood forecasting relates to the short lead times and to the need to provide distributed forecasts. Within the same storm event, a continuum of river reactions is triggered from a wide range of watershed sizes and impacts multiple disseminated target areas with various dynamics. The complexity of the hazard development often jeopardizes the generic flood management strategy.

A characterization of flood and flash flood events in Europe over various time and spatial scales is sought in this work as an important aspect of climate and hydrologic science in general, and to improve flood risk management in particular. We analyse these issues by examining i) the spatial scale of the concerned catchments, ii) the timescale of the catchment response time; iii) the spatial scale representing the density of the vulnerable targets in the impacted region, and iv) the timescale of the social response, which shape the preparedness strategy.

These issues are examined with reference to various riverine flood and flash flood case studies across Europe. Conclusions are reported concerning the potential and the limits of current monitoring and warning strategies.