JenKAS’ backbone is a handbook on climate sensible urban planning, which includes information on current and future local climatic conditions, legal aspects, economic assessments of adaptation options and best practice examples. The handbook is complemented by a decision support system tool called JELKA, specifically addressed to urban stakeholders and decision-makers. The tool was developed to make climate risk information more accessible and provide tailor-made recommendations, i.e., propose suitable adaptation measures for a specific policy field or a particular spatial unit.
The redevelopment of the Inselplatz is one of the first specific interventions for which the JenKAS approach aiming at mainstreaming climate change adaptation into urban planning was applied. This intervention aims at transforming the existing greyfield area into a new campus of the Friedrich Schiller University, also including adaptation measures to cope with heat stress-related risks. In a first step, JELKA was used to pre-select adaptation options to be considered for three alternative drafts for the redevelopment of the area. Then PRIMATE, a software for Probabilistic Multi-Attribute Evaluation developed at the Helmholtz Centre for Environmental Research - UFZ was applied to systematically compare these three drafts by means of multi-criteria analysis. The alternatives vary in: (a) number of trees and crown characteristics (small or large crowned trees), (b) colour schemes of pavements (ordinarily- or light-coloured cobblestone, respectively with an albedo of 0.3 and 0.5), (c) use and size of water bodies (none, water body of 40 m2, or water body of 80 m2) and (d) size of green roofs (31%, 50%, or 70% of total roof surface).
In order to compare the three alternatives the following four criteria were considered: (i) heat stress level (quantitative evaluation), (ii) costs (monetary evaluation), (iii) architectural quality (qualitative evaluation), and (iv) amenity value (qualitative evaluation). To visualize how the three alternatives will develop over time, these parameters were modelled for three different periods: (i) the year 2021, the anticipated opening of the campus; (ii) 2021-2050 visual appearance in the medium-term, and (iii) 2071-2100 visual appearance in the long-term. The main results of the multi‐criteria assessment for the Inselplatz intervention were:
- Alternative 3 ranks first in the medium‐term (2021‐2050) as well long‐term perspective (2021‐2100). This option consists in: (i) conserving the existing 14 trees and planting 31 new one (27 large-crowed trees and 4 small-crowed ones); (ii) use light-coloured pavements for the entire area; (iii) develop roof greening of new flats roofs (30% tar‐gravel‐roof and 70% extensive green roof); (iv) construct an 80 m2 artificial water body.
- The heat stress level was estimated through an indicator ranging from 0 (no heat stress) and 10 (maximum heat stress). According to the analysis, it was lower for the third alternative. Following values of the indicator were calculated for this alternative in comparison with the other two (indicator values of alternatives 1 and 2 are indicated within brackets): (i) period 1981-2010 = 4.1, corresponding to medium (4.8 for alternative 1, 4.5 for alternative 2); (ii) period 2021-2050 = 5.2, slightly elevated (6.0 for alternative 1, 5.7 for alternative 2); (iii) period 2021-2100 = 6.7, moderately elevated (7.5 for alternative 1, 7.2 for alternative 2).
- Light‐coloured pavements and large‐crowned trees have a beneficial impact on site‐specific micro‐climatic conditions (those of the Inselplatz). The (presumably) higher costs also pay‐off with regard to the criteria amenity value and architectural quality.
- When comparing the net present costs of a small‐crowned and a large‐crowned tree over a longer period (i.e. 82 years), the costs were slightly higher for small‐crowned trees compared to those for large‐crowned trees. Furthermore, the latter has a more beneficial impact on site‐specific microclimate.
- The influence of an artificial watercourse is more ambiguous as it is quite costly and has – due to its dimension – only a limited impact on the microclimate. Its overall value largely depends on how it is assessed with regard to its influence on criteria as amenity value and architectural quality.
Works at Inselplatz started in 2018 and up to now mainly focused on the preparation of the construction site. Interventions are expected to be completed by 2024/2025 (Project group “Campus Inselplatz”).