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Urban flooding is becoming increasingly destructive in the Mediterranean region as more and more urban infrastructure and socioeconomic activities are exposed to flood risk. The metropolitan area of Athens, Greece, is no exception to this flood-prone regime, presenting a rich record of flood events during the last century. On February 22, 2013, a high-intensity storm that lasted 7 h hit Athens, severely impacting the transportation sector, hindering vehicle circulation and the overall performance of the road network. This paper studies the impacts of high-intensity storms in urban areas by examining the effects of the February 2013 Athens storm and the resultant flood event. Its novelty lies in the impacts quantification approach, applying cutting-edge traffic flow control methodologies in the form of macroscopic fundamental diagrams. It quantifies the storm's impacts on vehicular traffic in terms of operational disruptions during the event, by analyzing various traffic-related indicators, such as travel time, delays, speed drop and re-routing of vehicles, using data from the Athens traffic management center and urban freight vehicle fleets. Results show increased travel times, significant changes in routing and substantial speed drops, highlighting the disruptive effects of the flooding event on traffic. The importance of developing a qualitative and quantitative understanding of the effects of such events in urban areas is particularly high, considering the context of the changing climate and the increasing frequency and intensity of extreme weather events.

Taxi services account for a significant part of the daily trips in most of cities around the world. Due to the fact that most of the taxi markets are regulated by a central authority there is the need for developing tools for understanding the behavior of these markets to policy regulations and supporting decision makers. This paper presents an agent based model for simulating taxi services in urban areas. Taxi models presented in the literature can be grouped into aggregated, equilibrium and simulation models, with the latter having been studied to a lesser extent. Agent simulation is a powerful tool for analyzing such complex problems, where stochastic nature of the variables and spatial distribution hinders the application of aggregated models. The agent-based model is presented together with the behavioral rules of the agents and applied to the city of Barcelona, obtaining the optimum number of vehicles and performance indicators of the provision of taxi services under the dispatching operation mode.

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