Climate-smart cities for the future

Writer
Tan Chui Hua

Smart technologies are being used by cities to combat the effects of climate change, such as flooding and extreme heat waves. They enable cities to be more responsive and efficient in mitigating climate change and its consequences.

Cities mentioned in this article:
Norfolk, Mumbai, Rotterdam, Athens, New York City, Singapore, Sydney

Key takeaways

1	Rotterdam created a network of green roofs acting as storm water reservoirs.
2	Miami-Dade County appointed the world’s first Chief Heat Officer.
3	Athens launched an app to evaluate and direct users to nearest cooling centres.
4	New York City developed a heat warning system to anticipate heat waves.
5	Singapore employs smart technologies to manage its urban forests and parks.
6	A new smart pilot in Sydney manages parks and directs users to coolest spots.

A rooftop rainwater collection and management system in Rotterdam © Frans Blok/123RF

From more frequent and intense adverse weather events to rising sea level, the impact of climate change on cities is multi-faceted and likely to worsen over time. Increasingly, cities are adopting smart technologies as part of their strategies to mitigate such impact.

These technologies, with their ability to integrate and process raw data from sensors and cameras through data analytics platforms and digital solutions, help cities address the impact of climate change. For instance, real-time ground data provide accurate, up-to-date information on critical parameters such as stormwater levels and ambient temperatures, which in turn allow cities to make informed decisions to avert or mitigate the impact of related crises.

Such systems provide other benefits as well – such as long-term cost savings and enhancing the quality of life for citizens. As smart technologies become more widely adopted, they demonstrate that such investment goes a long way in boosting the climate resilience and liveability of cities.

Managing flooding risks

Flooding, especially for low-lying cities, has become far more serious in recent years with the increase in rainfall, sea level rise, and changes in weather patterns. Besides traditional measures such as sea walls and storm drains networks, coastal cities have also introduced smart systems to help manage their vulnerabilities.

Norfolk, a coastal city in Virginia, United States is one such flood-prone city that piloted a storm sensor system led by the Virginia Institute of Marine Science between 2016 and 2018. Water-level sensors were installed in selected locations to gather data on the intrusion of tidal waters and capacity of stormwater systems, and allowed emergency responders and city officials to forecast flooding risks. The system – ‘StormSense’ – has since been scaled up in Norfolk and replicated in other cities in Virginia. Norfolk has also recently partnered Google to furnish drivers with real-time alerts on flooded roads.

In Mumbai, India, increasingly severe flash floods have disrupted its economy and livelihoods. On top of improving its drainage systems, the government has recently installed more automated weather stations to gather rainfall data, which in turn supports flood forecasting via an integrated flood warning system. Additionally, the city has launched an app which provides live location-specific information such as rainfall and winds to help citizens pre-empt floods and other extreme weather events.

In Rotterdam, the Netherlands, flooding risk is exceptionally high with four-fifths of the city below sea level. “As a low-lying city in the Dutch river delta, Rotterdam is vulnerable to the effects of climate change. Climate adaptation – adapting Rotterdam to climate change – is absolutely essential,” said Arno Bonte, Vice Mayor for sustainability, air quality, energy transition and resilience.

The city has implemented an innovative approach to reduce flood risks by creating a network of green roofs acting as storm water reservoirs. Electronic valves in the tanks can be operated remotely to release the water when the drainage systems are less taxed. By linking these roofs to the weather forecast, the roofs automatically adjust their storage by releasing water in advance when heavy rains are predicted.

“As a low-lying city in the Dutch river delta, Rotterdam is vulnerable to the effects of climate change. Climate adaptation – adapting Rotterdam to climate change – is absolutely essential.”

Navigating heat waves

With increasing extreme heat waves, cities are particularly affected due to the urban heat island effect. Recognising the gravity of this challenge, Miami-Dade County, United States, appointed the world’s first Chief Heat Officer in 2021, with the task of coordinating projects on cooling, education, and infrastructure. Other cities, including Athens and Melbourne, soon followed suit.

In Athens, its heatwaves are projected to become three times more frequent in the near future. Current losses due to heat-related worker productivity reductions in the city are estimated to be almost USD 100 million per year. Mayor Kostas Bakoyannis, shared, “Climate change for our city means more frequent and dangerous extreme high temperatures for residents and for tourists who are critical for our economy. Unfortunately, Athens is not unique – heat is an emergency for cities across Europe and the world.”

To combat the problem, Athens has launched a slew of initiatives including establishing more green spaces and water fountains in the city. In 2018, the city took part in a project to improve its resilience via an app called ‘Extrema’, which evaluates users’ real-time personalised health risk and directs them to the nearest cooling centres. Extrema provides information for government users to manage crises such as hazard maps, and information management tools for cooling centres. Extrema is now used in multiple cities in Europe.

New York City has developed a heat warning system to anticipate heat waves. The city uses satellite data to draw up an interactive heat map, which alerts the government to the neighbourhoods and populations most vulnerable to heat waves. Such data, together with other datasets on population density and public transit networks, helps the city to establish locations where neighbourhood cooling centres – publicly accessible spaces with air-conditioning – are needed during heatwaves.

Managing urban greenery more efficiently

Singapore employs smart technologies to manage its urban forests and parks © Tanya Keisha/123RF

The drive to incorporate more green spaces to help mitigate the effects of climate change has been gaining traction in cities, and smart technologies are now essential to help governments manage their urban greenery more efficiently and effectively.

Singapore is known for its greening efforts, with over 40 percent of its land area covered in greenery. Singapore employs a range of smart technologies to manage its urban forests and parks. Its National Parks Board tracks around six million mature trees remotely via an application which uses artificial intelligence and LiDAR point cloud datasets to assess the overall stability of individual trees under different weather conditions such as heavy storms.

The agency also uses satellite remote sensing to monitor the health of trees, deploys tilt sensors on mature trees to detect sudden movements, and dispatches drones equipped with digital cameras to inspect treetops. These initiatives allow the government to quickly identify trees that are unsafe to the public and ensure thriving, healthy green spaces.

Sydney Olympic Park © Maggie Yap/unsplash

In Sydney, a new pilot launched in 2022 deploys smart technology to manage parks. A partnership involving the government, several universities, and the private sector, the project at Sydney Olympic Park merges environmental monitoring and artificial intelligence to create cool microclimates in the 42-hectare parkland during summers. Weather forecasts and data from sensors installed to measure soil moisture and air temperatures jointly predict the watering needs for the different sections of the park to ensure optimal irrigation. Visitors may also use their mobile phones to check for the coolest spots in the park.

For the near future, climate change and its impact will likely be more challenging, with cities facing more vulnerabilities even as nations strive for net-zero emissions. In the meantime, cities have demonstrated that their climate resilience can be improved and enhanced by adopting multi-pronged strategies leveraging smart technologies, infrastructural investments, and comprehensive climate change policies. O