Global economic and social impact of coastal cities cannot be denied, but they are also among the most vulnerable to the effects of climate change. Extreme weather conditions such as storms, floods, and rising sea levels further threaten these areas. A study conducted by an international team led by Professor Matthias Garschagen from Ludwig-Maximilian University (LMU) in Munich highlights the significant challenges faced by coastal cities in adapting to climate change.

Global adaptation in different regions
The study's results, published in the journal Nature Cities, reveal that knowledge about adaptation varies worldwide. While research is more common in cities of the global North, those in the global South receive significantly less attention. Although the study includes 199 cities from 54 countries, most research efforts are concentrated in developed countries. Given the significant differences in wealth and resources, approaches to adapting to climate risks, such as rising sea levels, storms, and floods, vary greatly.

Technical measures, such as building levees and changes in urban planning, are more common in wealthier regions, while in poorer areas, such as parts of Africa and Asia, residents and businesses mainly rely on their own resources to cope with climate challenges.

Effectiveness of adaptations
Although significant progress has been made in some countries, many adaptations are not sufficiently effective in terms of speed, depth, and scope. Researchers have noted that most cities are trying to optimize existing disaster management systems based on past experiences, and it is rarely questioned whether these systems will be sustainable in the future. For example, Ho Chi Minh City faces serious risks from expanding into flood-prone areas, building infrastructure that will be further exposed to disasters in the future.

According to Garschagen, it is essential to accelerate adaptation and incorporate deeper changes into the risk management approach. Currently, adaptation processes in coastal cities are moving too slowly relative to the pace of climate change.

Vulnerability and social factors
Another key barrier to adaptation is the lack of quantification of risks and insufficient assessment of social vulnerability. Many cities consider future natural hazards such as floods and heatwaves, but rarely assess changes in demographics, urban growth, and social vulnerability. Such trends, Garschagen emphasizes, are crucial because cities like Lagos or Jakarta will not be the same in 20 years. In this sense, better scenarios and models are needed to better assess future risks and how cities can respond to them.

A question that is being asked more frequently is when and where it becomes more sustainable to stop investing in coastal defense and instead consider relocating populations. This is a question that researchers are increasingly analyzing, especially in the context of vulnerable areas such as Manila.

Differences between rich and poor regions
Another aspect that has proven crucial is the deep disparity in approaches between richer and poorer regions. In North American and European cities, adaptations mostly involve large technical and institutional measures, such as coastal protection systems and urban planning changes. In lower-income regions, such as Asia and Africa, residents rely on their own initiative and resources to cope with growing risks. This inequality only exacerbates the vulnerability of these communities.

Moreover, the study showed that, although there is progress in legislation and planning, most cities still lack long-term and sustainable risk reduction plans. Professor Garschagen calls for greater efforts in research and implementation of measures in cities of the global South, which are currently significantly underrepresented in scientific research.

Potential changes and future adaptations
Despite all the challenges, there are positive examples of adaptations in some cities. Singapore, Hong Kong, and several Swedish cities are implementing additional preventive measures and ecosystem-oriented approaches to protect infrastructure and reduce risks from future climate changes. Legislative reforms and improved planning show that these regions are on the path to deeper adaptation, while many cities at the mid-level of adaptation, such as Rotterdam and Helsinki, have successfully integrated new measures into their development plans.

Despite the progress, Garschagen warns that urgent and far-reaching changes are needed to ensure the long-term resilience of coastal cities to climate change.

Source: Ludwig-Maximilians-Universität München