Opinion – Claudio Bernardes: Climate change and the resilience of cities

The concept of resilience has been used a lot lately in the analysis of the operation and functioning of cities, and it has special importance when the evaluation involves risks arising from climate change. Resilience to urban climate change is directly linked to the adaptation of cities to these changes. This can be achieved through actions that will mitigate risks of natural disasters, but at the same time recognize the complexity of rapidly growing urban areas, and the uncertainties associated with these changes.

There seems to be no single action that will make a city resilient to climate change. Resilience will be achieved through various actions, building on each other over time. These actions can be improved and improved as cities use learnings from past experiences to make future decisions more efficient.

For the structuring of successful models that manage to make cities resilient to climate change, it is important to be aware that the urban areas most susceptible to shocks and stress arising from these changes are those that have fragile ecological systems, and large percentages of the socially marginalized population. or economically. These impacts are felt more by vulnerable people as a result of their high exposure to hazards, in addition to a lower possibility of adaptation and response, due to physical limitations or financial capacity.

The direct impacts of climate change are twofold: sudden shocks and impacts such as storms, typhoons and heat waves; and impacts that gradually increase over time, such as rising sea levels, rising average temperatures, and long-term changes in rainfall patterns.

Indirect impacts include: severe flooding (disrupting port or rail operations, affecting commuting and preventing goods from reaching their destination); increased risk of waterborne diseases; power blackouts, and thermal stress, exacerbated by rising temperatures at certain times.

The United Nations Environment Program has estimated that the global cost of adapting to these climate impacts is expected to grow to US$140-300 billion per year by 2030, and US$280-500 billion per year by 2050.

According to a report by the Asian Development Bank , the structuring of models for planning cities that are resilient to climate change must be elaborated through an iterative, inclusive and integrated process, which involves the connection of three types of evaluation: urban analysis, particularly understanding how the city works , examining its current status and future trends (such as population growth and spatial development); climate change risk analysis, in particular projecting direct and indirect climate impacts; and vulnerability analysis of the urban population, which faces a high risk of exposure to the impacts of climate change, and has limited capacity to face these impacts.

On the other hand, scenario development can be a powerful tool to plan for urban climate uncertainty. The analysis of these scenarios can be used to focus on the impacts of climate change on the course of urban growth trajectories or even to understand how climate change can affect specific sectors in the functioning of cities, such as water supply.

Resilience planning involves developing a strategy that documents the cumulative understanding of current and future vulnerability and identifies actions to build resilience over time. The prioritization of these actions will define what can be done immediately, and how the resilience deficit in the city can be reduced in the future.

No less important, however, is the analysis of urban systems. Systems thinking provides the platform for a more holistic approach, in which urban areas are considered complex “living” systems, undergoing numerous dynamic exchanges at any one time.

At this time, when all attention is focused on COP-27, it is imperative to make city managers aware of the importance of planning and implementing transformative actions to adapt to climate change. In the course of this process, learning and the exchange of information between cities can become a collective effort, fundamental for adapting urban areas to these ongoing changes.