How are cities responding to the growing risks of extreme weather?

Today’s cities face huge challenges in both preparing for and recovering from the growing impact of extreme weather events.

From extreme heat across southern Europe to the heaviest rainfall on record in Shenzhen and Hong Kong, to flooding in Brazil and cyclones devastating parts of southern Africa, cities face unprecedented physical risks.

Four in five cities across the world now face significant climate hazards such as heatwaves, floods and droughts, according to non-profit CDP, which surveyed 998 cities. Much of this extreme weather is down to a changing climate, and in the latter part of 2023, it’s coupled with the cyclical effects of El Nino.

“Many cities are facing multiple threats from extreme weather,” says Jeremy Kelly, Global Director of Cities Research at JLL. “While they currently establish longer-term resilience plans, they’re also having to deal with the immediate consequences of unprecedented and costly weather events.”

Changing weather patterns have huge implications for real estate and the people that live in cities. For nearly a third of cities surveyed by CDP, climate-related hazards pose a threat to at least 70% of their populations.

More than 90% of the world’s largest companies will have at least one asset - offices, factories, warehouses or data centers - financially exposed to climate risks such as water stress, wildfires or floods by the 2050s, according to S&P Global.

Rising temperatures have broken records for longer and more intense heatwaves in multiple urban areas in recent years. Cities, in response, are implementing a range of policies and measures to cool their streets.

Heavy rainfall is a critical threat facing many of today’s cities. Research from C40 looking at almost 100 member cities, found flooding could cause $64 billion of damage to urban areas each year by 2050, even with current levels of flood protections in place.

Meanwhile, non-profit First Street Foundation and engineering firm Arup identified 730,000 retail, office and multi-unit residential properties at annualized risk of flood damage in the U.S. costing over $16.9 billion a year by 2052.

Some cities, especially those in coastal areas, are already taking pre-emptive measures. Shanghai, New York and Cardiff are improving their “sponginess” by implementing inner-city gardens, improved river drainage and more vegetation.

After a 2011 rainstorm which cost around $1 billion in damages, Copenhagen constructed its Enghaveparken. Located at the bottom of a hill, it contains numerous chambers to hold and safely manage heavy rain. Rotterdam’s Watersquare Benthemplein, equally transforms from a sunken public plaza and basketball court into a major stormwater basin during heavy rain.

The storms that often bring heavy rain are also causing disruption to infrastructure and business as usual operations. It’s leading some cities to invest in microgrids, self-sufficient energy systems that can generate and store their own power and distribute it locally to connected buildings.

In Columbus, Ohio, a severe storm in 2022 left hundreds of thousands of residents without power for nearly a week. The city recently installed the first of five planned microgrids with 100 kW of onsite solar generation and 440 kWh of battery energy storage. San Diego is likewise investing in eight microgrids to support both short-term resilience and its longer-term goal of being powered 100 percent by renewables by 2035.

“Today’s cities need to be willing to think boldly about potential resilience measures and collaborate widely to share knowledge about what is working,” says Kelly. “Cities like Melbourne, Sydney, Amsterdam and Paris have been pioneers in developing climate resilience strategies but as climate risks continue to mount, even these will need to evolve. No city can afford to be complacent about what increasingly extreme weather means for their buildings or people.”