Can cities adapt to extreme weather events? – DW – 31.10.2024

For some Lagosians, pulling discarded plastic bottles, aluminum foil balls, cans and other waste from sewers and gutters means more than just making the city cleaner. It can also mean the difference between wading through puddles or having their homes completely flooded.

“It worries me when we see so much garbage and blockages in our drains and canals,” said Betty Aihoje, a volunteer with Reswaye, a Nigerian organization that works to educate people about the problems caused by littering. “Trying to keep our drains clean and clear helps us save a lot or problems with our buildings and the environment in general.”

Problems like flooding. Nigeria’s largest city will receive less rainfall on average in the coming years. But when it rains, it will likely be heavier, experts say. Clearing the drains is just one small step, although authorities have said the drainage systems will need to be upgraded and reconstructed to prevent further flooding.

Lagos is just one of many urban centers around the world that are having to adapt to the effects of rising temperatures.

Cities, home to more than half of the world’s population, are warming faster than rural areas. They have to find ways to deal with increasingly frequent and intense heat waves, droughts, rains, hurricanes and wildfires caused by people burning fossil fuels for energy, transport and industry.

The way cities are built can increase risks from extreme weather conditions. Volumes of concrete used to build roads and buildings can heat up cities and prevent excess rainfall from running off, leading to flooding.

Awareness of this problem is growing. In the 2023 Climate Hazards Survey of 169 urban administrations responsible for 1 million inhabitants or more, 122 reported that flooding has a moderate or severe impact on their cities.

Concrete also retains heat, making heat waves worse. It has serious implications for human health, urban infrastructure and society, says William Nicholls, head of the climate and sustainability group at global risk analysis firm Verisk Maplecroft.

“You have a number of ways that, for example, extreme heat can put pressure on energy and water systems. And there’s a literature that looks at how prolonged heat can affect things like political unrest and civil disobedience,” he added.

The heat is increasing in the cities

The number of extra hot days above 35 degrees Celsius is increasing in cities, especially in Southeast Asia and parts of Africa.

Planting trees is one way cities are trying to cope with the rising heat. Recent studies of the impact of street trees on urban temperatures have shown that an increase from no trees to 50% in a given location resulted in a 0.5 degree decrease.

“Extreme heat and flooding, one of the big things you can do to solve both problems is to restore natural places,” said David Miller, managing director of a group of cities known as the C40 Center for Urban Climate Policy and Economy and a former Mayor of Toronto. .

In the capital of Sierra Leone, Freetown, tree planting has become part of the city’s development plan. The city funds the program through tokens that are sold in the private and carbon markets. The city plans to plant a million trees by the end of the year, and experts say such projects have huge potential.

“The biggest benefits come from avoiding damage to infrastructure from natural hazards such as coastal erosion, flooding, sea level rise and landslides,” said Mykhailo Kapetanakis, an analyst at the International Institute for Sustainable Development.

Trees and forests can help counter the effects of extreme floods by slowing water flows, stabilizing soil and preventing landslides. They also absorb carbon dioxide, helping to reduce greenhouse gas emissions and combat air pollution.

There is potential to expand the project in Freetown to at least 3.8 million trees by 2050, said Kapetanakis, who weighed the project’s costs against its benefits. “It’s a very simple, cheap and reliable solution that solves many problems at the same time,” he told DW.

Cities with the highest climate risk

Cities in Africa and Asia are among those with the highest climate-related risk. Khartoum in Sudan, Mogadishu in Somalia, Ahmedabad in India, Hyderabad in Pakistan and Lagos are among the top five in the Verisk Maplecroft 2050 Climate Hazards and Vulnerability Index.

“Climate hazard and vulnerability is really a unique combination of the physical threat faced and the city’s ability to deal with that threat,” said Verisk Maplecroft’s Nichols.

For example, a country like Nigeria in the Global South and a country in the Global North like Germany can experience equally intense heavy rains, but people in Nigeria will be hit harder because there are fewer mechanisms to help them cope.

While urban areas in North America and Europe also face increasing challenges from extreme weather, better infrastructure, better disaster response and better access to health care are making residents less vulnerable, Nichols said.

Still, even in the wealthier Global North, there are people who are more vulnerable than others, says Thandile Chinyavanhu, a Stop Drilling, Start Paying campaigner at the NGO Greenpeace International.

This is also supported by the Urban Climate Risk Survey, with administrations in both rich and poorer cities reporting that it is particularly low-income households, the elderly and disabled, children and other vulnerable groups who are most affected by extreme weather events.

“There is a pronounced impact on communities that are the poorest and most vulnerable, as infrastructure is not as developed as in wealthier areas,” Chinyawanhu told DW. For example, in Johannesburg, South Africa, where poorer communities tend to settle in areas that are more prone to flash floods because they cannot afford places with better drainage, she said.

Making a difference in vulnerable communities

Some cities are trying to make changes in low-income neighborhoods to address multiple social and environmental issues. In the American city of Boston, organizations and residents have come together to create parks in poorer neighborhoods that will also help protect the city from climate warming.

Planned changes to Moakley Coastal Park include the integration of seawalls into the park landscape, the use of saltwater tolerant vegetation and rain meadows.

“The idea is that when you get a 50- or 100-year storm, these parks will be a place to absorb the water. But the rest of the year they serve the needs of local recreation in a place that desperately needs such facilities. ” said Miller.

Improving conditions in poorer areas can have far-reaching positive effects. But the problem many cities are facing is the increasing number of informal settlements that are springing up to accommodate the increasing number of people moving into the cities.

“For example, we see cities like Lagos where a huge amount of unplanned development is a huge part of where people live. It is clear that climate change is very difficult to deal with. There is no structure to support it,” Nichols said.

Working with the poorest people to meet their needs can help, Miller said. For example, people in the poorer areas of Freetown, Sierra Leone, without the energy to cook, cut trees for firewood. There, authorities are working with communities in informal settlements to provide them with more efficient and cleaner alternatives for cooking.

“I think the world’s best practice comes from the philosophy that if you’re going to address climate change, both its impacts and causes, you have to speak directly and involve the people who are affected by it in all conversations. the majority,” Miller said.

Financing change in global cities

However, one of the main challenges to implementing solutions in cities is funding, especially in the Global South, Miller added.

A report by the United Nations Environment Program published in 2023 says that despite the need for increased funding to developing countries to help them cope with the effects of climate change, funding flows have declined.

According to the Intergovernmental Panel on Climate Change’s Sixth Assessment Report, currently planned adaptation measures can already reduce the impact of global warming on both richer and poorer communities. Implementing all possible adaptations, which would require more funding, could further reduce climate inequality.

In 2022, funding provided by industrialized countries to pay for changes to help communities in developing countries cope with the effects of warming reached US$32.4 billion, roughly half the goal of doubling adaptation funding by 2025.

“If you think about adaptation projects, especially the most modern ones, then significant investments are required here. So we need to mobilize huge amounts of capital, and we need to mobilize it very quickly,” Miller said.

Additional reporting by Odunayo Oreyeni in Lagos.

Edited by Gianna Gruen and Tamsin Walker

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