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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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OPINION: The Swiss obsession for the sun is a recipe for frustration

When it comes to weather, Swiss people have a one-track mind. Only the sun will do. Perhaps their proximity to the Mediterranean has made them yearn for a better climate. They need to accept the grey days, Clare O’Dea argues.

OPINION: The Swiss obsession for the sun is a recipe for frustration

The Swiss climate, at least where most of the people live in the Central Plateau, delivers a mixed bag of weather. There are sunny days, wet days and foggy days. We have falls of snow in winter, heatwaves in summer, hailstorms, and winds with quirky names – the warm Foehn and the cold Bise.

Yet for the sun-worshipping Swiss, the only right weather is sunny weather. The global climate crisis has had little to no effect on this obsession with being bathed in sunlight. The longing for sun runs deep in the Swiss psyche.

Who would want to be a weather forecaster in Switzerland? A big part of your job is to apologise to viewers or listeners that they are being denied their due dose of sun on that particular day. For 55 percent of daylight hours every year, the sun is behind the clouds, and that keeps everyone wanting more.

The weather men and women address the public as if their main purpose in life was pleasure seeking. It doesn’t matter how many days of drought the country has suffered; the focus will be on the possibility of spending the day outside in the sun.

Skiing without sun is considered a minor tragedy

Hikers, lake swimmers or skiers are their target audience. The poor famers don’t get a look in. Anyone temporarily and unjustly trapped beneath low fog, will be advised where they can escape to sunnier altitudes.

It is true that some regions of Switzerland are afflicted by long spells of low-lying fog. There I have more understanding for the sun fixation. These fog interludes occur from late autumn to spring, mostly along rivers and lakes where the air is very damp.

Low lying fog can be the source of much frustration for the Swiss. Photo by Samuel Ferrara on Unsplash

According to MeteoSwiss, the dry air of the north-easterly Bise causes low-lying fog to rise. Strong, persistent Bise wind can mean that the low cloud cover does not lift for several days or even weeks. It’s tantalising for some during those cold, grey days to know that the sun is shining above the stratus, not far away in the mountains.

For most of Swiss history, people avoided the mountains, unless they were unlucky enough to live on or near them. Now, thanks to tourist infrastructure first built for rich foreigners, the mountains are the playground of the Swiss, easily accessible in winter and summer.

But the first rule of a successful weekend is that it has to be sunny. Whatever activity you undertake, the first question people will ask is whether it was sunny. Skiing without sun is considered a minor tragedy. Little attention is paid to the harm of high temperatures and the regular problem of drought. Every day of sun is a win!

A nationwide epidemic of seasonal affective disorder?

In fact, there seems to be a general lack of awareness of how crucial precipitation is to the Swiss ecosystem, agriculture, water and energy supplies. Instead, every day of rain is greeted as an imposition.

Could it be that Swiss people have a physiological need that is driving all this? A nationwide epidemic of seasonal affective disorder? It doesn’t seem to be a version of SAD because the sun hunger is no less pronounced in the summer, when it is sunny more often than not.

Let’s not be too harsh. I’m not the Ebenezer Scrooge of sunny weather. While writing this article, the sun came out for the first time in many days. I was drawn outside for a break and I turned my face to the sky gratefully. It’s just that I don’t miss the sun terribly when it’s not here. I know it will always come back, and, eventually, with a vengeance. In the summer, I spend most of my time seeking shade.

One part of Switzerland is living the dream, where daylight hours are sunny more than 50 percent of the time. The rest of country looks enviously towards Ticino, known as the sun balcony of Switzerland, for its extra hours of sunlight. Not surprisingly, the canton on the south side of the Alps is the number one destination for domestic tourists.

Italy the top destination for Swiss residents seeking sun

There is a mass migration of Swiss to warmer climes in the summer. A 2022 survey by the insurer Generali showed that Italy was the top destination for Swiss residents taking holidays abroad (29%), followed by France (18%) and Spain (16%).

The inconsistency of Swiss weather is probably what wears people down and feeds the sun fixation. There is a perception that the summer should be warm and dry all the time but May to August is also when it rains the most.

The proximity to the Mediterranean doesn’t help. It’s frustrating to be so close to the European region with the ideal outdoor climate and to get a taste of that in your own backyard on some days but never often enough.

If I may advise, rather than fighting against reality, a little acceptance would take a lot of the frustration away. There’ll be plenty of dazzling days in the summer, don’t worry. It’s just that the pattern will be unpredictable. And, whether we like it or not, winter is actually meant to be a grey time, where we make our own light and find different joys. If it’s any consolation, the sun is always there, whether we can see it or not.