19-08-2021

Extremer weather forecasted for urban areas

By Linde Kattenberg

In the last months, many cases of severe weather conditions were observable around the world. From floodings in China and Western Europe, a heatwave in North America, to fires in Southern Europe. The occurrence of these events highlights the devastating effect that the changing climate can have on our living conditions. The new IPCC report presents extensive evidence that these events are linked to human induced climate change, and that their occurrence is projected to become more frequent.

In anticipation of more severe weather conditions, building resilience to these risks becomes increasingly important. Floodings, heat waves, heavy rainfall, heat, wildfires and drought should be top of mind for policy makers, especially in cities. Urban areas play a vital role, because of their high population density, and their central role in economic activity. Additionally, more and more people are expected to live in cities. In 2050, around 2/3rd of the world population is expected to live in urban areas.

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Note. Source: C40. Cities with a three month period where average maximum temperatures exceed 35°C in the baseline period (top) compared to those that are projected to experience these temperature extremes by the 2050s (bottom).

Extreme heat and floodings are two examples of risks that we should be aware of in risk projections. In the graph above, it becomes visible that an increasing amount of urban citizens are projected to be exposed to long periods of extreme heat. In areas close to the water, extensive rises in sea level are also to be expected, as can be seen in the graph below. Both of these projections are based on the RCP8.5 scenario, one of the greenhouse gas concentration scenarios of the IPCC.

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Note. Source: C40. Cities projected to experience at least 0.5 metres of sea level rise by the 2050s under RCP8.5.

The good news is that cities can be a frontrunner in adaptive policy making, because of their centered resources in terms of (human) capital and technology. In an effort to make cities more adaptive to climate change, urban climate resilience tools are introduced. These tools are meant for urban policy makers in order to assess climate risks, and create fitting solutions.

A recent study has assessed whether and to what extent these tools have been used by decision makers at the city level. The tools studied were developed by international and humanitarian organizations, in collaboration with local and national governments. In analyzing 27 of these tools, the authors find that only 10 of the studied tools are meant to support action taking in increasing resilience. On the other hand, the rest of the tools are merely designed to create awareness and share knowledge of risks. Another interesting finding is that 20 of the 27 studied tools focus primarily on recovering from occured climate disasters, instead of anticipating future risks. Also, 16 of the tools are only based on current climate risk, without controlling for the changing climate.

Overall, this hints at cities that are mostly accounting for short-term adaptations and recovery plans, as opposed to increasing the adaptive and transformative capacity of cities.

Only with a more wholesome picture of short-, and long-term risks, can cities plan urban development adequately in order to preserve their vital role. By investing in the right infrastructure, cities can improve their resilience against extreme weather and the living conditions for its current and future inhabitants.