Adding options to cities' urban heat island mitgation: The Smart and Urban Tree Approach

Abstract

The present contribution highlights approach, applied methods, and results of a recently conducted research project named Smart and Urban Tree. Thereby, the authors focussed on critical spots in typical European City centers, which are characterized by little to no blue-green infrastructure, high population densities, large assemblies of mineral surfaces of the existing building stock, and – above all – a heavy competition between usages and space consumption. Given that this competition for space is happening on sealed surfaces, and very often also below (energy and gas lines, water pipes, sewers, instances of public transport, etc.), traditional approaches of implementing blue-green infrastructure are often difficult (resulting in very small interventions) to (even) impossible. Toward this end, we investigated toward specific built superstructures that could be tailored for the specific urban situation regarding load-bearing structure, integration of greenery and different public functions and amenities, and shading effects. Such ventures have to be well-planned, adapted to local circumstances, and - to be successfully accepted by all involved stakeholders – well worked out together with relevant stakeholders. These are, amongst others, neighbours of adjacent buildings, shopowners, occupants of the public space, politicians, administrative bodies, infrastructure providers, and many more. We used a specific case study location, a street in the densely populated 7th district of Vienna, which in short will require a surface redesign due a subway building site currently being carried out. We Approached the challenges by design (e.g. Fig. 1) and simulation-based evidence evaluation regarding thermal impact on both adjacent dwellings and the street corridor. Moreover, we conducted a set of structured stakeholder interviews with scientists of different disciplines (traffic sciences, infrastructure economics, spatial planning, planning law, sociology, heritage/monuments protection, etc.), local stakeholders (union of local trade companies), and executive/magistrative bodies (local politicians and administrative bodies, firefighters, etc) to find out about the potential of our envisioned structures.