Protecting coastal cities from climate change

Protecting coastal cities from climate change

A number of recently published reports are telling coastal cities around the world what they might already know: rising water levels and tides are putting them increasingly at risk for flooding. The damage caused could rise to $1 trillion worldwide by 2050, while cities in low-income countries could become “giant bathtubs.” Impeller takes a look at recent findings and how some cities are taking steps to protect themselves.

The effects of climate change will soon be “severe, pervasive and irreversible” if left unchecked, according to a recent report from the UN’s Intergovernmental Panel on Climate Change (IPCC).

“Our assessment finds that the atmosphere and oceans have warmed, the amount of snow and ice has diminished, sea level has risen and the concentration of carbon dioxide has increased to a level unprecedented in at least the last 800,000 years,” says Thomas Stocker, Co-Chair of IPCC Working Group I.

The IPCC is calling the report, produced by over 800 scientists, the most comprehensive assessment of climate change ever undertaken. According to the report, substantial reductions of greenhouse gas emissions are at the core of limiting the risks of climate change. Adapting and preparing for risks will also play a key role in preventing damage.

The news was not any better last year, when a study led by World Bank economist Stephane Hallegatte and the OECD pinpointed cities around the world that were most threatened by flooding. The study, Future flood losses in major coastal cities, found that the total costs of flood damage could rise to $1 trillion by 2050 if cities fail to take steps to adapt.

The ten cities facing the greatest risk in terms of overall cost of damage were: 1. Guangzhou, 2. Miami, 3. New York, 4. New Orleans, 5. Mumbai, 6. Nagoya, 7. Tampa, 8. Boston, 9. Shenzhen, and 10. Osaka. According to the IPCC report, hundreds of cities in tropical and subtropical regions are the most vulnerable. They can expect more tidal surges, stronger typhoons and storms, and deeper droughts.

Many cities around the world are already taking steps to protect people and infrastructure from flooding.

Following the $19 billion in damage to New York City after Hurricane Sandy, the city has several projects underway to limit damage from future storms. The $335-million Big U project, for example, would wrap lower Manhattan in a series of parks and walkways incorporating berms and barriers to prevent flooding.

In Jakarta, which could be underwater by 2030, a 21-mile-long seawall is being built along with 17 artificial islands to help protect the city from flooding – at the cost of $40 billion.

Fewer resources are available in the Philippines, which is still recovering from the estimated $36 billion of damage caused by super-typhoon Haiyan last year. A master plan for flood prevention in Manila has been created but is in its early stages.

“Every city and every sector of our country and society is at risk,” says Yeb Sano, the Philippine government’s climate change commissioner. “The IPCC tells us it will probably get 4°C warmer. That means everything will be compromised, from food and energy to settlements. We are not ready.”

Read about how Xylem is helping communities prepare for flooding and build urban resilience, and Xylem’s new project to protect Manila from monsoon flooding.

by Simon