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How Switzerland’s largest cities are combating the heat

It has been extremely hot in Switzerland in the past weeks and forecasts call for more of the same. Mountains can provide some relief but what about urban centres? This is how Zurich and Geneva are tackling the heatwave.

How Switzerland’s largest cities are combating the heat
Large trees provide shady canopies. Photo: Pixabay

While meteorologists have referred to this summer as “record-breaking”, with temperatures reaching 40C, the recent heatwave is a not new phenomenon per se.

With temperatures gradually rising for years due to climate change driven by the global warming, Swiss cities have become the so-called “urban heat islands” — densely populated zones where buildings and paved roads trap and absorb the heat and release it into the air.

READ MORE: 40C: Switzerland set for another heatwave

According to a report by RTS public broadcaster, “the effect of heat islands is greater in areas with a high built-up density and fewer green spaces”.

In Geneva, for instance, the districts of Pâquis, Plainpalais, Eaux-Vives, and Pont-Rouge are particularly affected.

In Zurich, the densely populated city centre and the area around the train station are the two hottest spots.

This Youtube video explains where Zurich’s urban heat islands are located.

How do the two cities counteract the effect of these heat bubbles?

According to climatologist Martine Rebetez, the best way to generate coolness is “an urban forest with vegetation on the ground and tall trees so as to create a continuous canopy”.

In Geneva, for instance, 21 percent of the urban zones have these kind of canopies, and the city’s objective is to increase this coverage to at least 25 percent by 2030.

Between 2020 and 2022, 900 trees, have been planted in Geneva specifically for this purpose.

However, as the TSR report points out, this coverage is unequal and seems to be income-based.

“In Florissant, the second-highest income district of the municipality of Geneva, more than 30 percent of the territory is under foliage. In Pâquis, on the other hand, where the median income is much lower, the canopy barely covers 5 percent of the area”.

What about Zurich?

Aside from green areas already in the city, municipal authorities are not only planting new trees but are also replacing those that had to be cut down due to damage.

A new feature is a giant fogger that was recently installed on the Turbinenplatz, one of the largest squares in the city. As soon as the thermometer passes the 30C mark, it sprinkles fine particles of water, cooling the air by up to 10C.

“The contribution of trees to the climate of the city remains unequaled”, said Simone Brander, head of Zurich’s public works at during the inauguration of the fogger.

“Sometimes technical innovations like this artificial cloud can serve as a sensible addition to reduce heat as well.”

READ MORE: How to keep your cool during Switzerland’s heatwave

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For members


‘Don’t sleep naked’: How to get a good night’s sleep in a Swiss heatwave

As temperatures climb again, many people may struggle to get a good night's sleep in Switzerland. Here are some expert tips to help you even when it's sweltering hot.

‘Don’t sleep naked’: How to get a good night’s sleep in a Swiss heatwave

Switzerland’s summers tend to get hotter and this season has seen its share of heatwaves, bringing temperatures closer to 40C and making it almost impossible to sleep.

This could mean trouble for residents of a country better prepared to bear the cold weather than the extreme heat.

The Swiss Federal Office of Public Health (FOPH) has three ‘golden rules’ for how to make it through heatwaves; avoid exercise during the hottest part of the day, keep the heat out of your house however you can, drink and eat smart (fresh foods and lots of water).

With night temperatures in some regions above 20C, Swiss residents will also need some help getting through the night.

Here are a few tips to keep cool overnight and enjoy better sleep despite the heat of the night.

Don’t sleep naked

It’s tempting to ditch the PJs when it’s this warm overnight. But sleep experts say this is a mistake, as any moisture from sweat accumulates on your body.

Cotton pyjamas and cotton sheets are very effective in absorbing and removing sweat from your body.

Give a little help to your internal clock

Many people think that it is only the extreme heat in summer making your sleep seem a bit worse than in the colder months. But the fact that days are brighter for longer makes a huge difference.

READ ALSO: How Switzerland’s largest cities are combating the heat

As light suppresses our body’s production of melatonin, the hormone that signals that it is time to sleep, the longer days irritate our internal clock, according to sleep experts.

The old tip of turning off your devices to avoid the blue light is also extra crucial. So around one hour before going to bed, you can start your “darkening” ritual throughout your home.

In that sense, it’s also better to avoid naps during the day to keep a better sleep routine.

Try to cool your room and yourself

Of course, the cooler temperatures are in your bedroom when you go to sleep, the better. You can help get temperatures a few degrees down by following these tips: keep the blinds and windows shut during the worst of the day and ventilate the cooler night breeze during the night.

Sleeping during a heatwave can be difficult. Photo: Yuris Alhumaydy / Unsplash

You can also moisten your curtains just before bedtime and leave the window open; the water evaporation will make it a bit cooler. If you can, another tip is to put your mattress on the floor as hot air rises – excellent advice for those sleeping on a bunk bed.

Don’t forget to turn off (and unplug!) electrical appliances, as those are heat sources.

READ ALSO: Eight great swimming spots to escape the Swiss summer heat

To cool yourself, you could take a lukewarm evening shower (not a hot one, those will make your body react by generating heat).

Fans and humidity help

As long as you’ve kept your room relatively cool, fans work. They help evaporate sweat which, in turn, helps your body regulate its temperature.

Putting a bowl of ice in front of the fan can also help cool the room.

Some people swear by dampening their sheets before going to bed. But if you’re not used to it, the feeling can be a little disconcerting. You can also place multiple ice containers in the corners of your room, which will melt slowly overnight and cool the air.

Why is it essential to have a good night’s sleep?

Several days of scorching temperatures can cause heat stress, according to the Swiss Tropical and Public Health Institute.

If the nights are not cool enough, the body can’t recover from the heat of the day, creating a dangerous condition called “thermal stress”, which can be fatal for the elderly and other vulnerable people.

While there are no statistics showing how many people have fallen victim to heat stress during the most recent heatwave, several cantons have implemented a system of home visits and frequent phone contact with this at-risk group.

READ MORE: How to keep your cool during Switzerland’s heatwave