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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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Nine injured in Swiss Alps avalanche

Nine ski hikers escaped with their lives after being caught by a major avalanche high in the Swiss Alps on Saturday, emerging with only light to moderate injuries.

Nine injured in Swiss Alps avalanche

All nine were found by rescuers and helicoptered to hospital, police said. The avalanche was triggered near the summit of the Alphubel mountain in the Saas-Fee area of the southwestern Wallis canton, close to the Italian border.

The site is near Switzerland’s iconic Matterhorn mountain and the plush ski resort of Zermatt.

“While groups of varying sizes were on the Alphubel at an altitude of 4,000 metres, an avalanche was triggered. Several were swept away by the mass of snow,” a Wallis police statement said.

Emergency services quickly scrambled to the scene in several helicopters.

A Wallis police spokesman told AFP that there were 16 people ski touring in the area, all of whom were taken off the mountain.

Nine were airlifted to hospitals in the nearby towns of Visp and Sion. Of those, three were able to leave after outpatient treatment and the others were being kept in overnight under observation.

“We’re talking about very light injuries so it’s looking positive,” the police spokesman said. “They were very lucky, we can say that.”

The other seven people on the mountain were unaffected by the avalanche or were able to extricate themselves uninjured. They too were airlifted off.

The police are not aware of any other people unaccounted for.

Emergency rescue services were on alert in the Wallis Alps due to the high numbers of winter sports enthusiasts taking advantage of the favourable weather over the Easter holiday long weekend.

Switzerland’s Institute for Snow and Avalanche Research (SLF) said the avalanche risk for Saturday was 2+ (moderate) in southern Wallis, on the scale of 1 (low) to 5 (very high).

Fifteen people have died in avalanches in Switzerland between October 1, 2022 and March 31 this year, while one person remains missing, the SLF said.

The figure is close to the 20-year average of 17 deaths.