Climate Academy 2021: Rethinking urban development
Reducing disaster risks and strengthening climate adaptation with nature-based solutions (NbS)
What can NbS contribute?
© Zita Sebesvari (UNU-EHS)NbS can't do everything. If, say, a century storm surge event is imminent, even a sponge city won't be able to do as much. Nor will a meter-high tsunami be stopped by a mangrove planting. But for the "average" risks, NbS can be incredibly valuable!
NbS are often less expensive than technical engineering measures and require significantly less maintenance. According to Ingrid Coetzee of ICLEI, nature takes care of itself if you treat it well. NbS often fulfill multiple objectives: they can contribute to long-term adaptation to the consequences of climate change and, in very concrete terms, make a valuable contribution to disaster risk reduction. At the same time, they provide a healthier urban climate and, in the best cases, even create additional livelihood opportunities.
Case studies from the Academy participants' presentations provided evidence of these benefits. Large green parks in cities can significantly reduce temperatures during the summer months. Heat maps show this for many cities worldwide. In conjunction with urban gardening, this can also create additional sources of income. Trees in streets provide shade and thus coolness. Green spaces facilitate the infiltration of surface water during rainfall.
Siddarth Narayan of East Carolina University explained the benefits of NbS using a port in southern India as an example. The port is located behind an offshore island. This island itself and its coastline are covered by mangrove forests, which protect the port's infrastructure from flood damage and prevent erosion. Preservation of this ecosystem is in the port's own interest.
A major hurdle is the lack of knowledge among many decision makers and the general public. For urban planners, NbS is not yet part of standard training. Improvements are urgently needed here. In addition, scientific findings and experiences from NbS projects must be better communicated to the population. Academy participant Sahana Ghosh showed how this can be achieved. She works as a science journalist at Mongabay-India and provides information on a wide range of NbS projects and local actors in the Nature-based Climate Solutions News.
A third challenge is the participation of all stakeholders involved. Conflicts often arise over land use in NbS. Especially in cities, where space is scarce, a decision-making process for a new measure must therefore be found together with the affected residents. Otherwise, the NbS risks rejection by the population. They must clearly see the concrete benefits for the community and for themselves as individuals. Dr. Stephen Diko, from the Department of City and Regional Planning at the University of Memphis, used the example of Kumansi in Ghana to explain the basically high willingness of the population to further develop the city with NbS. "However, when it comes to concrete implementation, prioritization tends to be low." Other things such as sufficient health infrastructure, educational facilities or simply space for shops are often more important. Education and participatory action are key here.