Digital Twins for Climate-Neutral and Resilient Cities. State of the Art and Future Development as Tools to Support Urban Decision-Making

The increased effects of climate change in the built environment require a rapid and effective response to adapt urban settlements to the main impacts related to heatwave, extreme precipitation, sea-level rise, and so on. At the same time, there is not much time to reduce Greenhouse Gas (GHG) emissions that contribute to climate change and limit the mean temperature of the planet within the 1.5 °C imposed by the Paris Agreement. In this perspective, cities around the world have a key role toward carbon neutral and resilient targets. In parallel in the last years, we are witnessing the impacts of a big amount of data and information available at the city scale. There are many data coming from different databases that can be processed and managed to support the urban climate action planned and designed by decision-makers and urban practitioners, for example, to assess the carbon emission of the building sector or to simulate the effects of extreme precipitation or urban heat island and consequence behavior of the built environment. In this scenario, in the last years, among many different digital enable technologies available in the Industry 4.0 ambit, it has gained more attention in the field of urban planning and urban design the digital twin concept that could synthesize in a digital representation of the real-world data and information flow that could exchange from the physical side to digital representation and vice versa. The aim of the paper is to analyze the urban digital twin developed in last years in Europe to evaluate if and how they consider the climate change issue, in order to understand the state of the art, the applications developed for climate change and which is the level of experimentation in order to study and develop guidelines to build urban digital twin as a support tool for a climate-neutral and resilient city.