Abstract | Owing to the intensified urbanisation and the multiple stressors that are faced by contemporary cities, there is currently an ever-increasing interest for the development of urban-scale risk assessment methodologies targeting a wide spectrum of natural and man-made perils. Representative examples of such perils are the urban flash floods, the urban heat island effect as well as the air quality degradation, whose intensity and frequency have been increasing during the past years due to the adverse consequences of climate change. In this context, the present research offers a practical indicator-based methodology for providing spatially variable risk estimates across a city network that is likely to be affected by a variety of perils.
The proposed risk assessment methodology accounts for both the physical and the social risk dimensions, while particular emphasis is given in the definition of the vulnerability component, that involves indicators which account for the susceptibility (i.e., propensity to damage/losses) as well as the lack of capacity to cope. The explicit inclusion of indicators that depict the coping capacities of a city against a certain peril, enables the comparative evaluation of several alternative counter measures within the context of the proposed methodology, on the basis of their ability to reduce vulnerability and ultimately to mitigate risk. The method could be exploited, among others, within the framework of a first-order decision support system to eventually contribute in enhancing urban resilience to future hazardous events. The developed risk assessment framework is demonstrated herein by means of a case study urban-scale application, considering the flash flood peril in the city of Milan.