Implementation of a web platform to support integrated multi-risk assessment and climate risk management in urban areas

Disasters occurred throughout the world in the last decades, often fuelled and amplified by climate change, have shown how a multi-hazard or multi-risk perspective is essential for effective risk management and for planning efficient risk mitigation and climate change adaptation strategies. Multi-risk assessment is intended to be the overall risk arising from a series of possible adverse events and their interactions with the different specific vulnerabilities of the exposed elements.

To support multi-risk assessment and disaster risk management, a web-platform integrating multi-hazard risk data and conceptual models across Italy is being developed within the framework of the RETURN (Multi-risk science for resilient communities under a changing climate) extended partnership. The platform will allow users to explore and query information related to hazard susceptibility (e.g., seismic, hydrological, heatwave, landslide, and flooding hazards), vulnerability, and exposure of urban settlements and will allow for a comprehensive representation of risk analysis results. Its main goal is to support stakeholders and decision-makers in dealing with complex multi-risk assessments as well as comparing scenarios and design alternatives for risk mitigation/adaptation and increase the urban resilience. 

In this work, a series of case studies, referring to specific areas of the Italian territory, is implemented to exemplify and test the platform’s functionalities. A combined approach based on risk storylines and impact chains is adopted to interactively describe multi-risk analysis in urban environments, by including multiple hazards, with their possible interactions, and all the exposed urban assets with the objective of evaluating the socio-economic impacts and related risks. This method, characterized by a synthetic narrative description of realistic multi-risk scenarios, reporting main facts, events and their consequences, is particularly useful when there is the need to go beyond a purely probabilistic approach. For all case studies, along with the definition of a storyline, a graphical conceptual representation is provided through an impact chain, highlighting the causal relationships between impacts and their driving factors on the analysed urban context.

The web-platform will showcase the impact chains with the possibility to explore input and output data of multi-risk assessments and interrogate results, featuring both static and interactive menus. The platform’s technical implementation prioritizes adherence to international geospatial standards (e.g., OGC) and supports various data formats (e.g., shapefiles, raster, and web services). A minimum representation scale of census zones ensures uniform data with an adequate refinement. This preliminary work on selected case studies set the groundwork for the subsequent scaling up of the platform to cover the entire Italian territory.