The sweltering island nation has long prioritised adding greenery and shade at every corner. Could other cities do the same?

Heat is humanity's most lethal climate threat, taking more lives every year than floods, hurricanes and wildfires combined. And the risk is greatest in cities, which are warming twice as fast as the rest of the planet because of the urban heat island effect.

As dangerous temperatures become more common, the leaders of cities around the globe, from Paris to Phoenix, are strategically planning to throw more shade.

But it's the sweltering island nation of Singapore which may well already have the best shade infrastructure of any city on Earth. People here have long had their own tricks to deal with the torrential rain and sticky heat.

Chief among them might be the covered sidewalks. The origin of this public shade is unclear. Although these "five-foot ways" which tunnel through the ground floors of arcaded shops and houses, resemble the porticoes of Bologna, they may be native to Southeast Asia. Stamford Raffles, the British colonial official considered to have founded Singapore in the early 19th Century, wrote them into the first town plan in 1822.

Raffles mandated clear, continuous and covered passages on both sides of every street to ensure efficient transit in inclement weather. Over time, his "verandah-ways" fell out of favour. They were revived in modern form by Lee Kuan Yew, the powerful prime minister who guided Singapore to independence in the 1960s.

Lee was something of a micromanager and had a particular interest in climate and comfort. He believed that humidity was stifling the country's economic productivity. Indoors, he transformed Singapore into what journalist Cherian George called the "air-conditioned nation". Outdoors, he was fanatic about shade. Lee was known to lecture subordinates about the poor design of footpaths and promenades, sometimes kneeling on the burning hot ground to prove a point.

In the 1960s and 1970s, as Lee's authoritarian government erected towering public housing estates, architects kept the ground floors of every building open to the air, preserving the areas as communal "void decks" where residents could gather to catch a breeze. In the late 1980s and 1990s, Singapore's housing and transportation agencies directed the construction of freestanding metal canopies over the sidewalks to ensure dry paths to the nearest bus or train.

Today, the authorities claim to have erected around 200km (124 miles) of covered walkways. Try to imagine if New York's ubiquitous construction scaffolds were permanent sidewalk architecture and you might have some idea of what the immensely unattractive though functional achievement looks like.

In the US, real estate developers are required to set their buildings back from the street to let in more light, but in Singapore, they must contribute to the shade network by carving 8-12ft (2.4-3.7m) of pedestrian overhangs out of the ground floors of their buildings. Research suggests the canopies have an effect similar to that of a clean and well-designed bus shelter. Just as a shelter can make a wait for the bus go by faster, so too do Singaporeans report that a stroll under the walkways feels 14% shorter than a stroll under the sun.

"You're in a tropical region where it's always super hot, and always very humid," says Yun Hye Hwang, a landscape architect and professor at the National University of Singapore. With daily high temperatures hovering around 31-33C (88-91F) year round, "we always need shade," she adds.

When it comes to shade, almost everyone would prefer the leaves of a luscious canopy to a clunky aluminium roof, but trees can't always be the answer, says Lea........

© BBC