Heat

Unfortunately, we missed the chance for a better scenario several years ago.
But hey – have a consolation prize.

A little chocolate to sweeten your naivety?
Take a look at a more realistic level.

Oh – you still believe in a perfect world?

Did you really think there was a better scenario?
You dreamer, you.

Unfortunately, we can’t turn back time.
The past is gone for good.

Can’t handle reality?
It’s okay – we’ve got something to help you.

Hot and very hot days (defined as the hottest 1% of all summer days between 1981 and 2010) are more frequent and more intense today than in the past. The summer of 2023, with temperatures between 33 and 36°C, was the fifth warmest since 1864. The August heatwave was the longest and most intense ever recorded here.

Think all that matters is good swimming weather?

High temperatures, and the associated increase in ozone concentrations, are unhealthy – and for vulnerable people potentially dangerous.

With climate mitigation, average warming in the Swiss Plateau is expected to reach 0.6–1.8°C; without mitigation, 2–3°C. For the hottest day of the year, this could mean up to 5°C more. In Geneva, temperatures could reach 40°C.

It is not only peak values but also prolonged heatwaves and tropical nights that increasingly burden people and animals. 'Heat stress' may sound like a joke – but for older people, it can be fatal.

  • Without sufficient rainfall, soils and plants cannot retain moisture. Temperatures rise further as a result. back to Drought

  • Heat warms permafrost, leading to increased subsurface collapse and reduced slope stability. continue to Permafrost

  • In (high) alpine areas, heat can alter underground water flows, triggering landslides and debris flows. continue to Gravitational Natural Hazards

  • The greenhouse effect leads to higher Earth surface temperatures. back to Climate Change

  • Heat during critical growth phases causes crop losses. Heat-loving pests and diseases benefit. continue to Agriculture

  • Extreme heatwaves can cause glacier calving and collapse in addition to intensified melting, further reducing glacier area. continue to Glacier Retreat

  • Three generations of bark beetles per summer instead of two mean roughly three million additional beetles – and around 1,000 more infested trees. continue to Bark Beetle

  • Heat-loving species are increasingly expanding northward and to higher elevations. Cold-adapted or less mobile species come under mounting pressure. continue to Biodiversity

  • Lower soil moisture reduces evaporation and soil cooling. Without this cooling effect, heatwaves can intensify further. continue to Water Balance

  • At higher temperatures, trees absorb less CO₂ and at the same time lose more water through transpiration. This negatively impacts photosynthesis and can, over the long term, impair tree growth and health. continue to Tree Vitality

  • Habitats with suitable water temperatures are shrinking, making survival and reproduction increasingly difficult for fish. continue to Fish Mortality and Species Extinction

Optimists might say: summer will last a month longer.

By the mid-century, Switzerland could experience more than 30 additional very hot days per year. The hottest day could become 6–7°C warmer. In the Swiss Plateau and Alpine valleys, heat stress for people and animals will rise sharply.

Heat-related mortality will continue to increase, especially in Zurich, Basel, and Ticino. Urbanisation and an ageing population will also contribute to this trend.

  • Drought leads to extreme and prolonged heatwaves. Temperatures remain unbearably high for extended periods. back to Drought

  • Permafrost areas shrink dramatically, affecting subsoil stability and entire ecosystems. continue to Permafrost

  • Extreme heat can dry out and lead to the subsidence of loose slope material, which can set it in motion. continue to Gravitational Natural Hazards

  • Global warming leads to more heat. Drought further amplifies temperature increases. back to Climate Change

  • Extreme heat leads to yield losses or complete crop failure. Fieldwork increasingly shifts to early mornings or late evenings. continue to Agriculture

  • Heatwaves cause glaciers to lose volume at an unprecedented rate – irreversibly. continue to Glacier Retreat

  • If temperatures rise by 4°C, the number of bark beetle generations doubles. Populations increase exponentially, along with the number of infested trees. continue to Bark Beetle

  • Higher average and maximum temperatures affect species composition and distribution. There are clear winners (heat-loving, heat-tolerant, and mobile species) and losers. continue to Biodiversity

  • Dried-out soils absorb less water during heavy rainfall. Increased surface runoff can cause flooding. continue to Water Balance

  • Increasing heat stress further weakens trees, leading to higher mortality. At the same time, warmer conditions favour the growth of harmful organisms such as bark beetles and fungal diseases. continue to Tree Vitality

  • Existing habitats become unsuitable for many aquatic creatures due to rising water temperatures. The first species die out. continue to Fish Mortality and Species Extinction

That's it. RIP.

That's a bit too much.
Maybe go down a level?

Got it – you're really into extremes.

Game over.
Try a different level.

That extreme? You’ll find the matching soundtrack here.

We’re done with this planet.
On to the next!

Solutionsfor: Heat

The root cause of extreme heat can only be addressed through climate mitigation. Beyond that, we must learn to cope with it.

The Swiss Federal Office of Public Health (FOPH) provides a Heat Action Toolbox with practical guidance for dealing with extreme temperatures. These measures support the protection of public health and include information platforms for the population as well as preventive recommendations for particularly vulnerable groups.

Increasing the use of air conditioning may seem like an obvious solution, but it also increases energy demand.

References